Life style factors in late onset depression


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this study explores lifestyle factors like diet, exercise, socialization, leisure activities and alcohol, tobacco use in geriatric depression. it is a cross-sectional comparative study of elderly with depression and age, sex and education matched healthy controls.

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Life style factors in late onset depression

  1. 1. Lifestyle Factors In Late Onset Depression: A Comparison Between Treatment Seeking Population And Matched Healthy Controls. Thesis submitted in partial fulfillment of the regulations of the National Institute of Mental Health and Neurosciences (Deemed university) For the degree of Doctor of Medicine in Psychiatry Dr. Ramkumar G S DEPARTMENT OF PSYCHIATRY NATIONAL INSTITUTE OF MENTAL HEALTH AND NEUROSCIENCES (Deemed University) BANGALORE-560029 INDIA 2011
  2. 2. DECLARATION I, Dr. Ramkumar G S, hereby declare that the thesis titled “Lifestyle Factors In Late Onset Depression : A Comparison Between Treatment Seeking Population And Matched Healthy Controls”, was carried out by me under the guidance of Dr. Srikala Bharath, Professor of Psychiatry, Dr. P T Sivakumar, Asst. Professor of Psychiatry and Dr. Seema Mehrotra, Assoc. Professor of Mental Health and Social Psychology at the National Institute of Mental Health And Neurosciences (NIMHANS, Deemed University), Bangalore. I also declare that no part of this study has previously been submitted as thesis for any degree or diploma of any University. October 2010 Dr. Ramkumar G S
  3. 3. ACKNOWLEDGEMENTS My sincere thanks to Prof. Srikala Bharath who has been a constant source of encouragement and guidance over the last two years during the course of this research work. My sincere thanks to Dr P T Sivakumar and Dr Seema Mehrotra for their guidance and support. I am grateful to Dr K Thennarasu, Assoc. Prof. of Biostatistics for statistical assistance and Mrs Beena, (Nutritionist) for assistance in developing the scale for dietary assessment. I express my gratitude to all the staff of the Geriatric Clinic, NIMHANS who have always been most supportive. Special thanks to all the research participants who patiently sat through the interview and cooperated whole heartedly for this endeavor. I am thankful to all my friends at Kabini Hostel who have helped me with the statistical software, reference manager software and helping in putting the manuscript in order.
  4. 4. CONTENTS S. no Chapter Pages 1 List of Tables, Figures and Appendices i 2 Introduction 1-6 3 Review of literature 7-29 4 Aims and Objectives 30 5 Methodology 31-35 6 Results 36-43 7 Discussion 44-49 8 Conclusion and Summary 50-52 9 Bibliography 53-61 10 Appendices 62-84
  5. 5. List of Tables 1(a) Cross-sectional Studies on Diet and Depression……………………………….17 1(b) Cohort Studies on Diet and Depression…………………………….…………….18 2(a) Cross sectional studies in Physical Activity and Depression……….….…….20 2(b) Cohort studies in Physical Activity and Depression……………………………21 3 Studies looking at Socialization and Depression…………………….….………27 4 Socio- Demographic Data……………………………………………………..……..37 5(a) Comparison of Diet Parameters……………………………………………….…….38 5(b) Comparison of individual dietary item……………………………………….……38 6 Comparison of individual items for physical activity ……………………….…40 7 Comparison of individual items for socialization ……………………….……..41 List of Figures 1. Comparison of self reported opinion on diet………………………………………….39 2. Comparison of self reported opinion on physical activity………………..……….40 List of Appendices 1. Life style Assessment questionnaire 2. HDRS Scale (Hamilton Depression Rating Scale) 3. Hachinski Ischemic Score 4. Cumulative illness Rating scale for Geriatrics (CIRS-G) 5. Hindi Mental State Examination (HMSE) 6. MINI Screen 7. Consent form 8. Ethics committee approval letter i
  6. 6. This document is licensed under the Creative commons attribution license 3.0 Contact author at
  7. 7. 1 INTRODUCTION Elderly population is increasing globally due to demographic transition. As per the United Nations estimate the global life expectancy at birth which is now at 68.9 years (India-65.2 years) is expected to increase to 75.5 years (India -73.3 years) in 2050. The proportion of population over 60 years of age in the world is also expected to double from the current value of 11%. In absolute numbers the population over 60 years in the world has surpassed 700 million in 2009 and it is expected to increase to 2 billion in 2050 (1). There exist a marked difference in the number and proportion of the aged in developed and developing regions. While in the developed countries the proportion of the elderly is projected to increase from current level of one fifth of the population to one third of the population in 2050, the same for the developing countries is expected to increase from current level of 2/25th to one fifth of the population. Thus developing countries will tend to equal the current proportion of elderly of the developed countries by 2050. However this growth in the background of the lower levels of socio-economic development and the continuing higher prevalence of infectious diseases is going to pose a greater challenge. In India the population above 60 years in 2010 is 91.7 million (7.5%) and it is expected to increase to 315.6 million (19.6%) in 2050 (2). Though old age should not be considered as a disease the elderly are considered more vulnerable to disabling and chronic diseases such as cardiovascular, neurological, cancer, Diabetes, Hypertension, musculoskeletal and mental illnesses. Due to industrialization, rapid urbanization, and increasing demographic change with smaller families, the pattern of life is undergoing rapid change. Adult members are increasingly forced to migrate to urban areas in
  8. 8. 2 search of livelihood. These changes are having direct impact on the health care needs of the elderly. Mental health in the elderly The geriatric population is affected by the same psychiatric disorders as younger adults however Dementia and Delirium have greater prevalence in comparison (3, 4). Depression is the leading cause of disability when measured as Years Lost to Disability (YLD) and the fourth leading contributor to the global burden of disease when assessed as Disability Adjusted Life Years (DALYs). By year 2020 Depression is projected to reach the second place in the ranking of DALYs calculated for all ages and for both sexes (5). The lifetime incidence of depression is 26.9% for men and 45.2% for women in people up to 70 years of age (6). The prevalence of depression in the total population is generally estimated at 5-8%. In elderly people (usually 65 years old and older), the prevalence is generally estimated at 12-15%. The prevalence is even more higher in elderly who seek out- patient care ranging from 18% to 36% (7). The prevalence of Major Depressive Disorder in individuals more than 65 years was estimated to be 1.4% in women and 0.4% in men with over all prevalence of 1% (8). A recent study (9) also report higher prevalence rates in women -12.4% vs. 7.8% in men however this gender gap becomes narrower in the ―oldest old‖ (10). The prevalence of sub- syndromal depression in the elderly population in East Asia is about 8-9% (11). Other epidemiological studies have reported prevalence rates ranging from 1%- 5% (10, 12). The low percentages of prevalence rates in many epidemiological studies are believed to be underestimations because of the difficulties in detecting depression in elderly. Patients and care givers may wrongly attribute it to the ageing process and identifying the symptoms
  9. 9. 3 when they coexist with medical illness may need skilful observation by the physician. It has been noted that older people tend to report more physical complaints and under report depressed mood making it difficult to use the established diagnostic criteria for the depressed in the elderly. Very often they have combination of mild depression symptoms, ―non- dysphoric‖ depression, dysthymia, persistent dysphoria associated with anxiety, pain in multiple areas etc. Prevalence percentages can also vary because of population studied, sample size, definition of depression, and method of diagnosis. Geriatric depression in India. In the Indian setting studies report higher prevalence rates for depression in comparison to studies from the west. A community survey in the year 1976 (n= 1060, all age groups) reported that the incidence of mental health disorders in the people above 60 years was higher (75/ 1000) compared to younger age groups (13). A study done later by the same authors in 1997 which was also a community survey of people over 60 years (n=183) reported the prevalence of total mental morbidity as 612/1000 and depression as 522/1000 population. Depression was the most common mental disorder in this study (14). A community survey of people more than 50 years (n= 408) in South India found that psychiatric disorders were present in 35% (350/1000)of the elderly population out of which the prevalence of depression was found to be much higher than any other psychiatric disorder- 59% of the diseased (15).Another study put the prevalence rate of mental illness at 89/1000 with depressive illness accounting for 67% of mental disease burden in a community sample of 686 elderly (16). In a study conducted in rural population in northern India the prevalence rate of psychiatric morbidity was 43.3% and the commonest diagnosis was neurotic depression, Manic Depressive Psychosis (MDP) depression, and anxiety state
  10. 10. 4 in descending order of frequency (17). A recent study from Mumbai has indicated that the point prevalence of depressive symptoms in more than 60 years elderly is 45.9% (18). Geriatric Depression- Characteristics Geriatric Depression may represent a heterogeneous group of disorders that differ in etiology, pathophysiology and prognosis, some of which may be distinct from the depressive disorder experienced by younger adults. One example of heterogeneity is the distinction between the late life patient with Recurrent Depressive Disorder (RDD) with onset of first episode early in life (Early Onset Depression– EOD) and the older patient with onset of major depressive illness after age of 50 years (Late Onset Depression– LOD). Comparison of Late Onset Depression (LOD) and Early Onset Depression (EOD). Patients with LOD have lower family history of depression and greater magnetic resonance imaging abnormalities (MRI) abnormalities compatible with ischemic cerebrovascular disease (19, 20). Vascular Factors (Hypertension, Coronary Vascular Accident, Ischemic Heart Disease and Diabetes Mellitus) were found to increase the risk of depression in the LOD (21-26). In a study (unpublished thesis) it was seen that patients with LOD had more impairment in executive functions indicating a frontal lobe involvement when compared with EOD (27) . LOD was also seen to be associated with more neurological soft signs and cognitive deficits than EOD. The increased association of cognitive impairment with LOD supports an underlying organic origin (23,28) and LOD may be a possible fore runner for Alzheimer‘s dementia (8,29). Based on phenomenology EOD is understood to be associated with more feelings of guilt (30, 31) and psychotic symptoms (32). It is also associated with more agitation and anxiety
  11. 11. 5 symptoms while LOD on the other hand is associated with more somatic complaints (33). Apathy is more prominent in LOD than in EOD (31). However some studies did not find any difference in phenomenology between the two types (34). An Indian study reported a trend to increased agitation and restlessness rather than retardation in the depressed elderly when compared with younger adults(16). The higher family history of affective disorders in EOD compared to LOD might indicate a greater importance of genetic factors in EOD (32,33,35-38). LOD is associated with greater life stressors and has greater chance of becoming chronic rather than recurrent (39).Two different etiological pathways are also proposed for LOD -one through the experience of severe life stressors and the other through biological changes in the brain (40). In a community based longitudinal study (41) which compared women with LOD, EOD and No MDD( Major Depressive Disorder), no difference between groups was found on marital conflict and social support. Those with EOD scored higher than those in the LOD and No MDD groups on neuroticism. Those with LOD reported poorer health than those with No MDD at 10 years prior to diagnosis. The authors suggested that poor health and not psychosocial risk factors or neuroticism predispose otherwise healthy adults to developing depression for the first time in late-life. An earlier Indian study (42) also reported that physical disabilities had significant association with LOD and it limits the movement of the subject and in combination with environmental conditions lead on to a feeling of loneliness and depression. However conceptually the critical question remains as to whether these differences result primarily from age associated physiological changes and a high prevalence of co-morbid medical conditions (differences in young vs. old patients) or whether late life depression is a disease entity distinct in its presentation, etiology, course and treatment response from
  12. 12. 6 illness affecting the younger adults (difference in EOD vs. LOD). LOD is also being increasingly considered as a life style disease especially because of its close association with vascular diseases for which lifestyle influences have been strongly demonstrated. Research by various groups internationally is active in this field and this study is being planned to explore the same in an Indian setting.
  13. 13. 7 REVIEW OF LITERATURE The Concept of Life-Style The simple sociological definition of lifestyle is ―the way a person lives‖.It includes aspects like consumption, entertainment, diet, social interactions and so on. It can be summarised as a conscious or unconscious choice of one set of behaviour over another. Lifestyles can be used for making broad social classifications based upon income and occupation, spiritual and religious preferences, traditional vs. modern, rural vs. urban etc. Lifestyle diseases also refered to as diseases of longevity are defined as diseases that develop as people live longer. This came from the realization that living long was good but the quality of life was also important. Changes in diet, lifestyle and environment are thought be behind the genesis of these disorders which affects quality of life in old age. Commonly referred life style disorders are Diabetes Mellitus, Hypertension, Heart disease, Stroke, Cancer, Osteoporosis, Cirrhosis and so on. Recent studies indicate that Dementia and other late onset psychiatric disorders like depression can also result secondary to lifestyle factors. These diseases directly influence morbidity and mortality in late life. The pattern of life style diseases is that they develop as degenerative process which has insidious onset, take many years to manifest and is difficult to cure. Depression however does not easily fit this pattern as its course can be self limiting with recurrence in episodic pattern although there is a tendency for chronicity in geriatric depression (39).But the fact that it can cause severe morbidity and disability is not widely known . Evidence for life-style diseases The existance of lifesyle diseases is exemplified by the differential incidence of diseases in different nations and cultures. The differential incidence of cancer between the western countries and the developing countries is linked to the difference in dietary pattern and
  14. 14. 8 physical activity (43). This study further adds weight to the said hypothesis by finding that the incidence of cancer takes on that of the host nation in people who migrate to it thus indicating that environmental factors are important determining risk factor rather than genetic factors for accounting for international variation in cancer incidence. This implies that modifiable evironmental factors can be put to advantage to reduce the incidence of these lifestyle diseases and therefore has enormous importance in a public health perspective. Studies have proven benefits of such interventions in various physical illnesses like in cardiovascular diseases, stroke and more recently in cognitive impairment (44,45). Life style and health outcomes The life style factors that have been found to influence genesis of physical illnesses are also plausibly thought to influence genesis of psychiatric illness. It appears logically possible especially in late life psychiatric illness like LOD and Dementia because of the increasing evidence of association of vascular causes with both of them. This area is being extensively researched by researches having affiliation to diverse disciplines. Many aspects of lifestyle are being looked into by these researchers and their approach has also been influenced by their disciplinary allegiance. The Alameda country study is a land mark study of a community cohort followed up from 1965 to 1999 (46). A study published from this cohort (47) examined the relationship between physical health status and health practices. They looked at hours of sleeping in the night, regularity of meals, physical activity, alcohol consumption, and smoking. They found that sleeping 7-8 hours per night, eating regular meals, participating in regular exercise, limiting alcohol consumption, and not smoking were highly correlated with healthier
  15. 15. 9 individuals. This study provided initial empirical support for the link between lifestyle and health outcomes. A 5.5 years follow up study (48) used the same parameters and additional ones of weight and BMI to study the relationship of lifestyle to mortality. It was found that those who ate regular meals including breakfast, received adequate sleep (7–8 hours), maintained healthy weight for their height, did not smoke, limited alcohol consumption, and participated in regular physical activity lived longer than those who did not practice these behaviors. However more recent studies did not find the relationship of not eating breakfast and snacking between meals to be associated with adverse health outcomes as previously noted. These health habits classified as ―good‖ became a standard and were investigated in many more studies looking at its relation to health outcomes including depression. It was found that depression prevalence rates were higher for six of the seven ―poor‖ health habits examined compared with the ―good‖ health habits (49). Multivariate regression analyses done in this study showed that a simple sum of the total number of good habits to be a significant independent predictor of depression after controlling for prior depression and various socio-demographic factors. Studies which have defined lifestyle as socio economic status and education have found increased depression to be associated with low income, low socio economic status and low education (50). Socio economic ststus and education can directly as well as indirectly mediate dietary patterns via influencing the availability, pattern of use of food and so on. Life style factors This study from a mental health perspective looks into five life style factors that could be influencing LOD by looking at a cross sectional population with depression as defined on conventional scale.
  16. 16. 10 Lifestyle factors that would be addressed in the present study are 1. Diet, 2. Exercise/physical activity, 3. Leisure activities including hobbies 4. Social interactions or Socialization. 5. Recreational alcohol use and tobacco use. Review of literature focusses on studies that have studied the above mentioned five factors. Interventional studies that look at change in depressive symptoms after its onset have been omitted as the current study focusses only on lifestyle factors that might influence genesis of depression in the elderly. [I] DIET The influence of one‘s diet on health is widely recognized in oriental culture from ancient times. Traditional medical systems have laid a lot of importance to dietary advice not only during time of illness but also in the healthy state. In modern medicine the importance of diet on one‘s health is being increasingly recognized. Although the influence of dietary habits and nutrition on physical illness is widely appreciated its influence on mental well being or illness is not known to many (51). Dietary pattern in general and deficiency of various nutrients like vitamins, minerals, and omega-3 fatty acids have been implicated in genesis of depressive symptoms in various studies. Epidemiological, co-relational studies and recent experimental studies find influence of various nutritive factors in depression. Some of these studies are reviewed below.
  17. 17. 11 Diet and General Nutrition A population based study investigated social and lifestyle factors that influence depression, anxiety disorders, sleep disorders and quality of life in men and women (age 18- 90yrs) (52). The authors found that the prevalence of depression was more in women and it was associated with self evaluation of nutrition as ―poor‖, low food intake and low paid jobs. Depression was also associated with smoking, alcohol abuse and dependence. Depression was also positively associated with vascular and gastro intestinal diseases. In a community sample of 267 male and female it was concluded that nutritional deficit and depression were associated after controlling for educational status, socio economic status and smoking (53). As found in the above mentioned studies malnutrition in general have been implicated to be associated with depression due to decreased appetite (54). However healthy elderly are also reported to loose weight when followed up over long period (55). Surprisingly evidence from elderly without mental illness seem to suggest a protective effect for obesity on depression (56). In a sample of 2406 men and women aged 70-79 years followed up after 3 years it was found that depressed mood at baseline predicted weight gain after 3 years. Also weight loss over three years predicted depressed mood at end of the three years. The authors attribute this effect to probable deterioration in general health associated with advancing age (57). In fact research on the association of obesity (as measured as Body Mass Index (BMI)) and depression has produced conflicting results (58) and more studies are reporting a protective effect of obesity for depression in elderly called popularly as the ―Jolly Fat‖ hypothesis (59, 60). In contrast other studies have reported a positive association of obesity with depression. This can be mediated by a co-morbid metabolic syndrome (61) and also indirectly by reduced health related quality of life from a sedentary life style (62). The
  18. 18. 12 relationship remains unclear with many studies reporting lack of association between depression and obesity (63). Depression and Nutrients The association of vascular nutritional risk factors and depression in an elderly cohort of depression (n=196, age more than 60 years) in comparison with non depressed subjects was studied. It was found that the depression group had higher intake of saturated fat and cholesterol, higher body mass indices, lower alcohol intake, and higher Keys score (a measure of the serum cholesterol-raising capacity of the diet) than the comparison group (64). After controlling for variables like age, sex, education, race, and medical co-morbidity, associations persisted for cholesterol, alcohol, and Keys score. Depression was found to be positively associated with overall dietary pattern as defined by total kilocalories, saturated fat, cholesterol, Body Mass Index, polyunsaturated fat, Sodium intake, and alcohol intake. The study concluded that the dietary pattern considered as risk factors for vascular illness differed between depressed and non depressed group. Mediterranean Dietary Pattern which contains an adequate intake of fruits, nuts, vegetables, cereals, legumes or fish ensures adequate levels of vitamin B12 and Folate have been postulated to influence depression in various studies. In a large cohort study it was investigated both cross-sectionally and longitudinally (65, 66). In the initial cross sectional analysis (n= 9670) it was found that Folate intake was inversely associated with depression prevalence among men, Vitamin B12 intake was inversely associated with depression in women. No significant association was observed for omega-3 fatty acids intake. The participants were reassessed after 5 years (mean follow up- 4.4 years, n= 10,094) for their adherence to Mediterranean diet and depressive symptoms. It was found that 480 new cases of depression were noted and adherence to Mediterranean diet was found to be protective.
  19. 19. 13 Dose-response relationships were found inversely related to fruit and nuts intake, monounsaturated to saturated-fatty-acids ratio, and legumes. A prospective epidemiological cohort study followed up elderly subjects (n= 610) for 6 years to look at the influence of dietary lipids on geriatric depression scale score (GDS) (67). In multivariate linear regression analysis, GDS score was found to be negatively associated with dietary intake of monounsaturated lipids (MUFA) and their main source -olive oil. GDS score was positively associated with intake of polyunsaturated lipids (PUFA) derived from one of the principal dietary source -seed oils. Intake of calories, total lipids, fish and seafood or saturated lipids was not found to be associated with variation in GDS score by this group. Depression and Consumption of Fish Other studies have found a negative correlation between Depression and fish consumption. A cross-sectional study with a sample of 3204 adults has found this correlation (68). In a study which compared between the national estimate of fish consumption pattern and prevalence of depression it was found that they were negatively associated (69). However both the methodological aspects of this study and the tendency in general to impute dietary explanations to any health condition has been critiqued (70). A study assessed the serum levels of fatty acids in a community based sample of elderly more than 60 years (71). Subjects with depressive disorders had a higher ratio of n-6 to n-3 poly unsaturated fatty acids (PUFAs) compared to healthy subjects. But difference in individual PUFAs between the groups was small. The study controlled for potential confounders like atherosclerosis, inflammation etc. In a prospective study there was no association of diet-related factors with late-life depression in a cohort of elderly men (n= 526; age 70 -89 years) (72). However a negative relation between physical activity, moderate alcohol consumption and decline in serum
  20. 20. 14 cholesterol level during the study period with depression was noted. The authors concluded that physical activity and moderate alcohol consumption may be protective in ―old-old‖ men. The study also found that a decline in serum cholesterol level may predict development of late-life depression. An earlier review (73) has discussed this issue by looking at studies which had similar finding and also those contesting it. They postulated that this inverse relation between cholesterol levels and depression could be mediated by another variable in the diet i.e. the reduced intake of dietary omega-3 poly unsaturated fatty acid (PUFA). This has probably resulted out of the increasing proportion of omega-6 to omega-3 PUFA in the diet over the years due to the changing dietary pattern. The inverse association between consumption of fish and depression was further explored as to whether it was mediated directly or indirectly (50) . Post hoc analysis of data from a large cohort study (n=10,602 men age, 50- 59 yrs) via regression analysis found that depressed mood was associated with fish intake both directly, and also indirectly as part of other factors in the diet and also as part of a lifestyle that was associated with depression. General Dietary Pattern and Depression The above studies and many other studies have looked more on the nutrients that influence mood states and also how supplementation of these could alter health states (not discussed in this review). A few recent studies have also look at it in a macro level i.e. quality of dietary patterns. Food frequency questionnaires were used to gather information about diet which were scored based on perceived quality. A study in an elderly cohort (mean age =55.6yrs) investigated the influence of ‗whole food‘ (heavily loaded by vegetables, fruits and fish) and ‗processed food‘ (heavily loaded by sweetened desserts, fried food, processed meat, refined grains and high-fat dairy products) on score on standard depression scale as outcome measure (74). The participants in the highest tertile of the whole food pattern had lower odds
  21. 21. 15 ofdepression than those in the lowest tertile. High consumption of processed food was associated with increased odds of depression. This study concluded that whole food pattern may be protective for depression. Mental health outcomes in women aged 20- 93 years using similar categories in the form of "traditional" dietary pattern ( vegetables, fruit, meat, fish, and whole grains), "western" diet (processed or fried foods, refined grains, sugary products, and beer) and ―modern food‖ (fruits, salads, fish, tofu, beans, nuts, yogurt, red wine) were studied. It was found that traditional dietary pattern was associated with reduced odds for depression and dysthymia. The authors concluded that the habitual diet quality and the prevalence of mental disorders were associated (75) . The deficiency of omega 3 fatty acid and vitamin B12 causes impaired mood state. Vegetarian diet has deficiency of these nutrients. 60 vegetarians were compared to 78 omnivores. It was found that vegetarians reported significantly less negative emotion than omnivores. The authors concluded that the vegetarian diet profile does not appear to adversely affect mood despite low intake of long-chain omega-3 fatty acids (76). Various review articles have also summarized the research findings in this area of diet and depression The various mechanisms of low fatty acids influencing depression like influencing the structure of brain and modification of fluidity of neuronal cell membranes have been comprehensively discussed in one of the review article (77). Another review has looked at risk factors for depression along with other aspects. It reports that depression is related to low serum Folate and vitamin B12 levels and increased serum Homocysteine levels (11). As the evidence from randomized controlled trials (RCT) for the effect of B vitamins and n-3 PUFAs is modest it was suggested that larger RCTs and meta-analysis needs be done to better understand its effect (56). A better way to throw light on the
  22. 22. 16 causality of dietary factors on mood and cognitive function would be to include them as outcome measure in studies that look at effect of dietary patterns as markers of physical health (78).
  23. 23. 17 (Table -1a) Cross-sectional Studies on Diet and Depression* Author, Year Place, sample Age (yrs) Design Scales, Diagnostic criteria Results Tiemeier et al, 2003. Rotterdam study.(71) Netherlands, 264 M&F >60 Community, Cross- sectional CES, PSE- 10,DSM IV diagnosis of depression Blood fatty acid composition related to depression. Averina et al, 2005. (52) Russia 1968 M &1737 F 18-90 Population based cross- sectional AUDIT, QOL & Depression scales. Depression positively associated with poor nutrition, low SES, adverse health behaviours (alcohol use smoking). Sánchez- Villegas et al, 2006. SUN cohort. (66) Spain, 9670 M&F University graduates Cross- sectional FFQ, Physician diagnosis of Depression. B12 intake in women & Folate in men inversely associated to depression; omega- 3 fatty acid intake not related. Payne et al, 2006. (64) US, 196. M&F > 60 Cross- sectional FFQ, Keys score Depression group had higher intake of saturated fat, cholesterol, higher BMI, lower alcohol intake, and higher Keys score. Appleton et al, 2007. PRIME cohort data. (50) Northern Ireland, France 10,602 M 50- 59 Cross sectional data from a cohort study Welsh Pure subscale for Depression from MMPI; FFQ Negative association of depression with dietary fish both direct and indirect via associated life style. Cabrera et al, 2007. (53) Brazil 267 M&F >60 Community, Cross sectional GDS, Mini nutritional assessment. Depression is associated with nutritional deficit. *M- Men, F- women, SES- Socio Economic Status, BMI- Body Mass Index, CES-D - Centre for Epidemiologic Studies Depression scale, PSE-10- Present State Examination, DSM-IV- Diagnostic and statistical Manual of mental disorders edition IV, AUDIT- Alcohol Use Disorders Identification Test , QOL- Quality Of Life, FFQ- Food Frequency Questionnaire, GDS- Geriatric Depression Scale, MMPI- The Minnesota Multiphasic Personality Inventory. Keys score (a measure of the serum cholesterol-raising capacity of the diet)
  24. 24. 18 (Table -1b) Cohort Studies on Diet and Depression* Author, Year Place, sample Age (yrs) Design Scales Results Timonen et al, 2004. (79) Finland 2721 M 2968 F Young adults Follow-up cohort from pregnancy to 31 yrs of age. HSCL-25, depression subscale, fish consumption over last 6 months. Fish consumption and Depression related only in women. Bots et al, 2007. FINE study. (72) Finland, 526 M >70 Prospective 5yrs Zung scale Dietary factors not related to Depression but negatively associated with physical activity and moderate Alcohol use. Kyrozis et al, 2008. EPIC- Greece cohort (67) Greece, 610 M&F >60 Prospective epidemiological 6 yrs GDS, dietary questionnaire. Low seed oil , high olive oil predict healthier affective state Sánchez- Villegas et al, 2009. Follow-up of SUN cohort. (65) Spain, 10,094 M&F adults Prospective 5yr FFQ, Physician diagnosis of depression. Mediterranean diet protective for depression Akbaraly et al, 2009. Whitehall II cohort. (74) UK, 3486 M&F Mean age=55.6 yrs Follow up cohort 5yrs CES-D; ―whole food‖ vs. ―processed food‖ categories Processed food pattern was associated with Depression Jacka et al, 2010 (75) Australia, 1,046 F ages 20– 93 years Cross-sectional GHQ-12, FFQ, category of traditional, western and modern food. Quality of diet associated with mental disorders. Western diet had high odds for Depression. *M- Men, F- women, HSCL-25- Hopkins Symptom Checklist Depression Scale (HSCL-D), GDS- Geriatric Depression Scale, FFQ- Food Freq Questionnaire, CES-D - Centre for Epidemiologic Studies Depression scale.
  25. 25. 19 [II] PHYSICAL ACTIVITY/ EXERCISE Physical activity is beneficial in people who are well and also on people who are unwell. Disease outcomes that have been found to be inversely related to regular physical activity in prospective observational studies are cardiovascular disease, thromboembolic stroke, Hypertension, Type 2 Diabetes Mellitus, Osteoporosis, Obesity, colon cancer, breast cancer, anxiety and depression (80). More and more of such evidence are available in recent times especially in relation to cognitive function (81,82). However there is lack of randomized controlled design to substantiate these findings though this evidence is considered in the same league as the evidence in other health related behaviors and outcomes like smoking, saturated fat intake and coronary heart diseases. Public health interventions have been initiated in terms of lifestyle alteration in these life style diseases without need for demonstrating the relation through randomized control trials. The American Heart Association in 2007 has updated its original recommendation (in 1995) about physical activity for the general public including elderly. It has stated the specific nature, type and frequency to be followed for better physical health. The mechanisms mediating such benefits especially the antidepressant effect which is the focus of this review have been hypothesized; namely, a) psychological mechanisms like increased feelings of self-efficacy, b) self perceptions of control and mastery c) reduced physiologic responses to stress, d) and beneficial effects on neurotransmitters such as increased serotonin and endorphins (83). Exercise and diet are also believed to mitigate the adverse effect of stress and ageing on the functioning of neurotrophic factors (84). The following studies are reviewed in detail.
  26. 26. 20 A cross-sectional study in community dwelling elderly women found that depression was inversely associated with physical exercise and directly with smoking. Non harmful alcohol use was associated with better cognitive performance(85) . A study examined cross-sectional and prospective association (after 5 years) between exercise and depressed mood in community dwelling elderly (86). Regular strenuous exercise and exercise <3 times per week were assessed and cross-sectional Beck‘s depression inventory (BDI) score were compared at two assessment points. Higher exercise rates corresponded with lower BDI scores. However when BDI scores of people who attended both assessments were compared longitudinally their baseline exercise levels did not influence their BDI score at five years. So the authors concluded that people who exercise have better mood. However it may not ensure better mood in future in non depressed people who also exercise. Table 2a: Cross sectional studies in Physical Activity and Depression* Author, Year Place, sample Age (yrs) Design Scales Results Kritz-Silverstein et al, 2001. Rancho Bernardo Study (86) California, 2029 M &F. 944M&F in follow up. 50- 89 Cross sectional and prospective 5ys BDI Exercise associated with better mood but not protective longitudinally. Cassidy et al, 2004. (85) Australia, 278 F only >70 Community cross sectional BDI> 10 Depression negatively associated with physical activity & positively with smoking *M- Men, F - women, BDI- Beck‘s Depression inventory.
  27. 27. 21 Table 2b: Cohort studies in Physical Activity and Depression* Author, Year place, sample Age (yrs) Design Scales Results Camacho et al, 1991. Alameda country study (87) Californi a, M&F Adults Longitudinal cohort 20yrs - High physical activity related to less depression Strawbridge et al, 2002. Alameda country study (88) Californi a , 1947 M&F >50 Longitudinal, cohort 5ys DSM-IV diagnosis of depression, physical activity scale Physical activity protective for depression Frederick et al, 2004. (49) Los Angeles, 752 M&F adults Community longitudinal screening CES-D; Life style habits Depression was associated with 6 out of 7 poor habits. Brown et al, 2005. (89) Australia, 9207 F Middle aged Prospective cohort ,5ys CESD-10, Mental health [MH] subscale of the Short Form 36 survey Association between increasing physical activity and decreasing depressive symptoms Wiles et al, 2006. Caerphilly study (90) UK, 1158 M 45- 69 Cohort: at 5yr and 10 yr follow up GHQ, Minnesota leisure time physical activity questionnaire Heavy intensity leisure time activity associated with less odds of Depression, the effect persisted at 5ys but not at 10yrs. Wise et al, 2006. Black Women‘s‘ health study (91) Boston, US 35,224 F 21- 69 Cohort follow up after 2yr, 4ys. CES-D Leisure time physical activity had reduced odds for depression. Bots et al, 2008. FINE study. (72) Finland, 526 M >70 Prospective 5yrs Zung scale Less Depression with physical activity and moderate alcohol use. Dietary factors not related. Ku et al, 2009. (92) Taiwan, 3778 M&F >50 Cohort 7yr follow up CED- D Leisure time physical activity has reduced risk for depression. Heesh et al, 2010. (93) Australia, 6653 F 73- 78 Community longitudinal screening GADS, Leisure Time Physical Activity scale(LTPA) Depressive symptoms on GADS score were negatively correlated with LTPA scores. *M- Men, F- women, CES-D - Centre for Epidemiologic Studies Depression scale, DSM-IV- Diagnostic and statistical Manual of mental disorders edition IV, GHQ- General Health Questionnaire, GADS- Generalized Anxiety Disorder [GAD]scale
  28. 28. 22 The studies that have looked at mental health outcomes from a longitudinal cohort have found that that men and women with low activity levels at baseline were at a significantly greater risk for depression at the 20-year follow-up than those who reported high activity levels (87). The relationship between physical activity and depression in older adults (50 to 94 years) was studied after adjusting for age, sex, ethnicity, socio-economic status, chronic conditions, disability, body mass index, alcohol consumption, smoking, and social relations. It was found that physical activity was protective for both prevalent and incident depression (88). Similar inverse relation between depression and physical activity has been previously discussed (72). A dose response relationship between self-reported Physical activity (PA) and depressive symptoms in cross sectional analysis was investigated by a prospective assessment in community dwelling middle aged women. Mailed questionnaire included questions about time spent in walking, moderate- and vigorous-intensity PA. Mean depression scores decreased with increasing levels of previous, current, and habitual activity (89). [III] LEISURE ACTIVITIES. "Play is any activity that has great meaning but no purpose.” -- Mark Twain Leisure activities are those that are freely chosen. This may be considered synonymous to play and recreation. It implies less of serious purpose but more of enthusiasm and joy. Leisure tends to be more associated with retirement but it occurs in all age groups. They are enriching and rewarding experiences in life. They give purpose and satisfaction in life. The potential physiologic benefits of leisure activities are probably derived from the exposure to an enriched environment, defined as a combination of more opportunities for physical activity, learning, and social interaction. It is believed that these experiences do not produce structural changes in the brain but functional changes .It also influence the rate of
  29. 29. 23 neurogenesis in adult and senescent animal models. Various aspects of leisure activities have been extensively studied especially their protective effect in cognitive decline and dementia (94) . Leisure activities may be generally divided into ingredients of social, physical and mental (intellectual) spheres. The differential effects of these components are well studied in literature pertaining to cognitive decline and dementia. However in studies looking at depression it appears that only the physical aspects of leisure have been considered. Social and productive activities that involve little or no enhancement of fitness have the ability to lower the risk of all cause mortality as much as fitness activities do (95). It is believed that in addition to increased cardiopulmonary fitness, leisure activity may confer survival benefits through psychosocial pathways. . The following studies have been reviewed in detail. A cohort study found that engaging in little or no recreational activity was associated with twofold increased odds of incident depression after 8 years in women. But no such increase was seen in men (96). Other epidemiological studies have however approached physical activities as part of leisure in general. The differential influence of leisure time physical activity and occupational physical activity with common mental disorders (CMD) as outcome in men (age 45-69) was studied by assessing the total leisure-time activity and percentage of time spent in heavy- intensity activity from self-reports. The leisure time physical activity was intensity scored as light, moderate and heavy. The energy expenditure was also calculated. Men were classified into four classes of occupational activity from least active to most active. The study found that those who participated in any heavy-intensity leisure-time activity had reduced odds of
  30. 30. 24 common mental disorders (CMD) 5 years later. There was little evidence that men in the most physically demanding jobs had reduced odds of CMD after 5 years. There was no association between physical activity and CMD at 10 year follow up (90). Women living in the community (n=35,224, aged 21 to 69) were assessed for past and current exercise levels at baseline. They were followed up after 2years using mailed questionnaire. It was found that adult vigorous physical activity during leisure time was inversely associated with depressive symptoms (91). Women who reported vigorous exercise both in high school (≥ 5 hr per week) and adulthood (≥ 2 hr per week) had the lowest odds of depressive symptoms relative to women who had never been physically active. Walking as an exercise negatively affected depression symptom onset only in women having BMI > 30. A similar study using mailed questionnaire in a community dwelling elderly women (age 73 -78 yrs) found beneficial effect of walking (93). They were assessed on their weekly minutes of walking, moderate leisure time physical activity (LTPA) and vigorous LTPA. Association between five levels of LTPA (none, very low, low, intermediate and high) and depression and anxiety scores were calculated. Inverse dose–response associations were observed between both LTPA/walking and depression scores in concurrent and prospective models. The results supported an inverse dose–response association between both LTPA /walking and mental health. Another study also found that low leisure time activity was associated with greater risk of developing depressive symptoms (92). A Review article while looking into the relation between physical activity and mood has evaluated the possible mechanisms that mediate it (97). The authors have dealt with psychological theories like distraction, self efficacy, social interaction and physiological theories that link positive mood changes to monoamine and endorphin levels. The authors
  31. 31. 25 after a systematic review of 87 studies concluded that moderate exercise elevates mood while heavy exercise can in fact deteriorate mood. A review article looks into basic and clinical studies that lead to a neurotrophic hypothesis of depression according to which stress and depression reduce neurotrophic factors and neuronal development (84). Neurogenesis is progressively reduced in aging and could potentially put the individual at risk for depression. Author inferred that the exercise and diet modulate antidepressant action via positively influencing neurotrophic factors especially in the hippocampus. All studies mentioned in this review looking at physical activity have focused on how physical activity directly influences health outcome. Some recent research looks specifically at the mediating variable like genetic diathesis that influence exercise behavior and health outcome. In a twin study (98) the twin who exercised more did not display fewer anxious and depressive symptoms than the co-twin who exercised less. The authors conclude that the association between regular exercise and reduced depression in population at large is not due to causal effect of exercise, but in toto a common genetic vulnerability to lack of regular exercise and risk for anxiety and depression. [IV] SOCIALIZATION Social participation which is an important psychological resource is beneficial in all age groups Studies have found that involving in social and productive activities can reduce mortality in the elderly similar to physical activities (99). It is hypothesised that if benefits from physical activities is due to better cardiopulmonary function, then social activities may confer survival benefits through psychosocial pathways (95). Better health benefits in people who do exercise have also been attributed to associated social interaction that occurs during the process.
  32. 32. 26 The following studies have been examined in detail. A community level cross-sectional survey of life-style used 16 items selected from the four factors of economic situation, physical health, social activity, and personal status(100). The study also investigated life satisfaction, morale, and physical function and it was found that the factors significantly related to depression in community dwelling elderly were the number of friends and morale. An increase in the number of friends was related to a decrease in depression. Depression in the ―old-old‖ elderly was more significantly related to many lifestyle items compared with the ―young-old‖ elderly. The extent of influence of socialization on depression was found more in the old-old. Another study looked at depression in both community-dwelling and institutionalized elderly (101). In the community study it was noted that ability to do activities of daily living and social activities were protective for depression. In the institutionalized elderly loneliness and poor perception of general health predicted depression. In a recent study from a cross- sectional sample of 55 elderly from India, it was found that loneliness was positively related to depression. However the amount of socialization was not found to be related (102). The study also found that loneliness was not related to sociability. It appears that the concept of loneliness appear to have more relevance in the subjective experience of depression.
  33. 33. 27 Table 3 Studies looking at Socialization and Depression* Author, Year place, sample Age (yrs) Design Scales Results Demura and Sato, 2003. (100) Japan, 1304M&F <75) vs. old old (> 75) Community survey, cross- sectional GDS> 10=high D lifestyle scale, Number of friends, morale, social activities related to depression. Kim et al, 2010. (59) Korea, 295M&F elderly Community, Cross- sectional GDS, scale for ADL, hand grip Perceived health status, ADL, hand grip and social activities predicted depression. Kim et al, 2009. (101) Korea, Japan 184M&F 65-98 Institutionalized elderly, comparison of cross-sectional assessment Health status, loneliness, Depression Loneliness and perception of general health were significant predictors of depression. Singh and Misra, 2010. (102) India , 55 M&F 60-80 Cross-sectional Eysenck sociability scale, BDI, UCLA loneliness scale Loneliness related negatively to depression while sociability not related to depression; loneliness not seen as lack of sociability, * M- Men, F- women, GDS- Geriatric Depression Scale , ADL- Activities of Daily Living, BDI- Beck‘s depression Inventory, UCLA- University of California Los Angeles Many studies have investigated the benefits of religiosity/ religious beliefs and spirituality in mental health. As the current study does not focus on this aspect but just explores it as part of activities, only a brief mention of the literature that investigates its association in geriatric depression is mentioned. Reciting prayers , watching television and listening to the radio , and participating in physical activity in community dwelling elderly correlated to lower depression for older men, but only watching television and listening to the radio related to lower rates of depression for women (103). Various studies have found that attending religious activities was a protective factor for geriatric depression (104,105).
  34. 34. 28 [V] ALCOHOL AND TOBACCO Many of the studies discussed previously have also looked into the issue of substance use and depression in the elderly. Direct relationship of alcohol and mood change in the form of depression has been well documented. Substance use can mediate depressive symptoms directly also indirectly via its influence on vascular diseases. Long term follow up studies have found a direct relationship between substance use and increased mortality. They have also found positive association of depression with tobacco and alcohol use (47,52,85). However moderate alcohol consumption was also found associated with less depression (72). Another study found that depressive subjects consumed less alcohol than non depressed subjects (64) . In a study among community dwelling elderly (n= 1280, 55-85 yrs) depression was assessed both cross-sectionally and longitudinally (at the end of 6yrs). It was found that depression was associated with smoking, a recent increase in the number of cigarettes smoked and sedentary lifestyle. There was also a trend towards association with excessive alcohol consumption (106). Summary of Literature Review Diet- Malnutrition is associated with geriatric depression as a cause and consequence. Although studies have conflicting results obesity may have a protective influence on depression. Dietary pattern that are associated with vascular diseases like increased intake of calories, saturated fat, alcohol, and smoking are also found to be associated with geriatric depression. Increased consumption of fish (omega-3 fatty acids) and mono unsaturated fatty acids intake seem to be protective for depression. Deficiency of various nutrients like omega-3 fatty acids, Vitamin B12 and Folate has been associated with depression. ―Whole‖
  35. 35. 29 food and ―traditional‖ food have been found to be associated with less depression. Vegetarian diet has not been associated with depression. Physical activity/ Exercise- There are consensus among the studies that physical activity/ Exercise have both cross-sectional and prospective positive association with depression. A few studies have reported that the prospective association is less clear. Physical activity is associated with less risk for depression. Heavy intensity occupational physical activity did not seem to protect against depression in men. Leisure activities – Various studies have found that involvement in recreational and leisure activities have been associated with less depression. However most studies have studied the physically active dimension of leisure activities. Studies looking at other dimensions like intellectual and social dimensions were lacking. Walking has been defined as a leisure time physical activity. It has been found to be protective for depression. Many studies have found an inverse dose- response association between leisure time physical activity and depression. Socialization and social Interaction- Various studies have found positive association between good social interaction and reduced depression. A few studies have reported that feeling of loneliness may have more salience in the elderly who are depressed. Alcohol and tobacco use- Geriatric depression has been directly associated with tobacco use and alcohol consumption even though a few studies seem to indicate protective effect for moderate consumption of alcohol on depression.
  36. 36. 30 AIMS AND OBJECTIVES 1. To compare the Life Style in elderly with Late Onset Depression (LOD) subjects with age and sex matched healthy controls .The five factors considered for the study namely- 1. Diet 2. Physical activity/ Exercise. 3. Social Interaction. 4. Leisure activity including hobbies. 5. Alcohol and tobacco use.
  37. 37. 31 METHODOLOGY SELECTION OF SAMPLE INCLUSION CRITERIA 1. Subjects more than 50 years of age. 2. Availability of a relative who can corroborate the information. 3. Satisfies DSM IV-TR (107) Diagnostic criteria for Major depressive disorder 4. Gives informed consent for the study. EXCLUSION CRITERIA 1. Onset of MDD before 50 years of age 2. Presence of other DSM IV Axis I psychiatric disorder 3. Presence of substance dependence syndrome except nicotine. 4. Presence of depression with psychotic symptoms. 5. Presence of chronic neurological conditions like Epilepsy, Multiple sclerosis, Parkinson‘s disease 6. Presence of cancer, recent myocardial infarction or cerebrovascular accident (within 6 months), AIDS. SELECTION OF CONTROLS INCLUSION CRITERIA 1. Age and sex matched healthy subjects. Attempts were made to match for education and socioeconomic factors to the extent possible. 2. Availability of a reliable relative. 3. Informed consent EXCLUSION CRITERIA 1. Presence of DSM IV-TR Axis I diagnosis 2. 3, 5 and 6 same as for exclusion criteria of subjects
  38. 38. 32 INSTRUMENTS FOR ASSESSMENT OF SUBJECTS AND CONTROLS 1. Socio demographic Questionnaire. 2. Hindi Mental Status Examination (HMSE) (108) 3. Mini International Neuro Psychiatric Interview (MINI) (109) 4. Hamilton Depression Rating Scale (HDRS ) (110) 5. Hachinski Ischemic Score (111). 6. Cumulative Illness Rating Scale for Geriatrics( CIRS-G) (112). 5. Life Style Questionnaire - Based on other standard questionnaires a Life Style Questionnaire that suited the Indian population was developed addressing diet, exercise/physical activity, alcohol and tobacco use, leisure and social activities taking into consideration expert opinion of nutritionist and statistician. METHOD Forty six patients with a diagnosis of Late Onset Depression attending the Geriatric Outpatient Services of NIMHANS and forty six healthy controls (matched for age, sex and education) with no psychiatric conditions were studied. DESCRIPTION OF TOOLS 1. Socio-demographic data sheet contained relevant socio demographic data, clinical history, and mental status examination. A diagnosis of depression based on DSM IV criteria was made. 2. Hamilton Depression Rating Scale( HDRS) (110) This is one of the most commonly used raring scales in studies on depression. It comprises of 21 items. Items are scored 0-2 and 0-4. It has good reliability and internal consistency. It takes 15- 20 minutes to administer. 3. Hindi Mental state examination (HMSE) (108) It is a scale that is adapted from MMSE for purpose of interviewing Indian population.
  39. 39. 33 5. MINI international neuropsychiatric interview- Screen (109). It is a truncated version of the MINI questionnaire for purpose of screening people for psychiatric disorder it is used along with schedule K of the full MINI that screens for psychotic disorder. 6. Cumulative Illness Rating Scale for Geriatrics (CIRS-G)(112) It is a modified CIRS was operationalised with a manual of guidelines geared toward the geriatric patient. In medically and psychiatrically impaired elderly subjects it gives reliable quantitative ratings of chronic medical illness burden for geropsychiatric practice and research. . The score gives an indication of the burden of vascular risk factors. It has 14 items each to be scored from 0 to 4 based on increasing severity. A total score, a severity index can be calculated from it. 7. Hachinski Ischemic Score(HIS) (111) A tool used in screening to differentiate vascular dementia from degenerative forms of the disorder. It has got 13 items which have to be scored either 1 or 2. Patients with a score of 7 or higher are more likely to have a vascular dementia. A low Hachinski Ischemic Score is less likely to indicate vascular dementia. 8. Life-Style Questionnaire was developed for this study based on other standard questionnaires from the West after consultation with the nutritionist and statistician. A comprehensive and easy to apply scale that measured all the items of life style in the Indian population was not available. Therefore the questionnaire developed included items which measure frequency and type of diet, extent of physical activity, socialization, leisure activities substance use and composite scores. The respondents were asked to reply on the variables during the period of one to two years before onset of depressive illness. Dietary assessments included whether the respondent was vegetarian or non vegetarian, Adequacy of food measured on ordinal scale on categories of no of meals, snacks and amount of water. Type of food was assessed based on broad categories like carbohydrate (with and without fiber separately), protein (non-vegetarian and vegetation separate), fats
  40. 40. 34 etc. Items were scored based on frequency of use from 1(never) to 3 (> 4times a week). The dietary items were made descriptive asking the subjects about the food they commonly consumed e.g. Anna (par-boiled rice), Mudde, idly, Dosa, Roti, Chappathi, Dhaliya, Kambu kalzhi, Puri were categorized as carbohydrate with fibre while Akki Roti, Anna ( Raw Polished Rice), Upma, Nan, Avalakki, Sooji, Sabudhanna Kanji were classified as carbohydrate without fiber. For certain items based on nutritionist‘s suggestion and after discussion with the three mental health professionals and the statistician the scoring were reversed e.g. eating chicken more than four times a week got lesser score of 1 compared to once a week- score of 3. Physical activities were measured on the number of activities and the frequency of exercise and also the number of hours spent daily in physically demanding activities. Household activities like cooking, cleaning, washing clothes, gardening and looking after grand children were specifically asked and scored. Leisure activities and hobbies were assessed on the number of activities reported and each activity got a score of one. Social activities were measured on ordinal scale form 0-5 and it was adapted from the Patient Version of questionnaire developed by the 10/66 Dementia Research Group (113). It included questions which assessed how far relatives and sibling stayed away from home, frequency of interaction with friends and children etc. The composite scores for each factor was calculated and the max score in each are Carbohydrate- 10, Protein- 18, Fat-6, physical activity- 15, Leisure activities- 16, socialization- 30.
  41. 41. 35 PROCEDURE Patients attending the Geriatric Clinic at the Department of Psychiatry, NIMHANS were screened for Major Depressive Disorders (DSM IV-TR codes 296.2x, 296.3 xs). Suitable subjects were clinically examined by the investigator. The diagnosis was confirmed by discussing with the consultant psychiatrist and cases with onset of illness after 50 years were recruited for the study. Patients who were previously diagnosed with depression and currently in partial or full remission were also included. The details of study were discussed with the subjects and a reliable relative and written informed consent was obtained. Hindi Adaptation of the Mini Mental State Examination was administered initially to rule out any associated cognitive deficits (dementia). Hamilton Depression Rating Scale (HDRS) was administered to assess the severity of the depression. Subsequently the Lifestyle Questionnaire developed for this study was applied. The subjects were asked to recall their life-style before the onset of depression and answer the questions. Using purposive sampling, controls matched for age, gender and education and who met the sample selection criteria were identified by ―word of mouth‖ and recruited for the study after informed consent. MINI screening questionnaire was applied in the control subjects to rule out psychiatric morbidity including depression. The recruited controls were assessed with the same tools applied on the cases. STATISTICAL METHOD Continuous variables were tested for their normal distribution and comparison between groups was done using Independent sample t test. Non parametric analysis of Wilcoxon Mann- Whitney test was adopted when distribution was not normal. Categorical variables were analyzed using Chi square test/ Fisher‘s exact test. P < 0.05 was considered statistically significant.
  42. 42. 36 RESULTS The study recruited a total of 92 subjects with 46 each in the case and control groups. The groups were comparable with respect to age, sex and educational status. (Table- 4). Two third of the subjects were between the ages of 50 -65 years age group (33 in LOD group and 30 in control group). The groups did not differ with respect to Body Mass Index (BMI).The groups differed significantly with respect to socio-economic status (p= 0.051).The depressive group had less subjects n=8(7.4%) in the low socio economic status than the control group n=18 ( 39.1%). There were significantly (p= 0.035) more subjects with vascular risk factors (Hypertension, Diabetes Mellitus or both) in the depressive group. The group did not differ significantly (p=0.178) in Cumulative Illnesses Rating Scale Scores (CIRS-G) - 3.2 ± 2.5 for cases and 2. 6 ± 2.3 for controls. The mean Hachinski Ischemic in the cases was 1.7 ± 0.8 and was significantly higher than in the control group (p<0.01).Since many of the cases were in remission from depressive illness and on follow up their depressive scores measure by HDRS ranged widely (5 to 35) and those who were admitted had higher scores.
  43. 43. 37 Table 4 Socio- Demographic Data Item Depression (n =46) control (n= 46) P value* Age ( mean in yrs) 62.9 ± 7.2 62.8 ± 8.3 0.947 Sex Men 20(43.43%) 22(47.82%) 0.834 Women 26 (56.57%) 24(52.18%) BMI 22.8 ±2.8 23.1 ±3.0 0.548 Education Illiterate 11 (24%) 9 (19.6%) 0.49 Less than 10 std 14 (30.4%) 19 (41.35) More than 10 std 13 (28.3%) 8 (17.4%) Degree 6 (13%) 5(10.7%) Post-graduation 2 (4.35%) 5 (10.7%) Socioeconomic Low 8 (17.4%) 18 (39.1%) .051Middle 33 (71.7%) 26 (56.5%) Upper 5 (10.7%) 2 (4.35%) Systemic illness HTN,DM or both 26 (56.5%) 15 (32.6%) .035 Others or nil 20 (43.5%) 31 (67.4%) * Chi-square/ fisher‘s exact test, T test Diet The two groups did not differ significantly with respect to BMI (p=0.548). Mean BMI in cases was 22.8 ±2.8 and in controls was 23.1 ±3.0. In detailed physical examination also they did not show any signs of malnutrition. There was higher percentage of vegetarians 22(47.8%) in the depressive group compared to the controls 13(28.3%) but this was not statistically significant (p=0.085). Many subjects - 9 in depressive group and 13 in control group, who called themselves non-vegetarians, were taking non vegetarian diet less frequently than once a month thus scoring similar to vegetarians in the diet scale measurements on non-vegetarian items. The analysis of dietary items was done as a group and also individually.
  44. 44. 38 The mean composite scores for dietary factors, physical activity, socialization and leisure activities did not differ significantly between LOD and the control groups (Table 2a).On comparison of individual items it was found that group with depression was taking significantly more dietary fiber(p<0.001) and dairy products ( p=0.03) (Table: 2b) Table 5(a): Comparison of Diet Parameters Depression (n =46)* control (n= 46) P value( T test) Carbohydrate 6.4 ± 1.7 6.1± 1.8 0.32 Protein 8.2 ±3.7 7.7 ±3.7 0.50 Fat 6.1 1.8 6.1 2.0 0.95 * Values represent Means of composite scores ± Standard Deviation Table 5(b) Comparison of individual dietary item. Depression** control P Value* Water 2.0± 0.5 2.3± 1.0 .241 Carbohydrate with Fiber 4.7± 0.8 3.9± 1.1 <.001 Carbohydrate without Fiber 1.8± 1.4 2.1± 1.2 .126 Fish 0.5± 1.0 0.6± 1.1 .412 Chicken 0.9± 1.4 0.9 ±1.3 .847 Meat 0.5± 1.1 0.6± 1.1 .647 Eggs 1.0± 1.2 1.1± 1.3 .637 Dairy products 2.5± 1.0 1.8± 1.2 .003 Veg. protein 2.7± 0.7 2.5± 0.8 .276 Fat 3.4± 1.2 3.4± 1.1 .899 Pufa 2.7± 0.8 2.0.±1.0 .752 Vegetables 4.1± 0.9 4.0± 0.6 .158 Fruits 3.2± 1.6 3.0 ±1.7 .493 *Mann- Whitney U test ** Mean scores ± Standard Deviation
  45. 45. 39 Depressive subjects reported that they felt their diet was very healthy before the onset of depression and this was significant when compared with control. (Fig- 1). Fig 1 Comparison of self reported opinion on diet* 0 5 10 15 20 25 30 very good moderate some- what Depression Control X axis= dietary pattern (very healthy, moderately healthy, somewhat healthy) Y axis= no. of subjects.* chi square test (p= 0.03) Physical Activity. There was no significant difference (p = 0.64) between the LOD group and the control group with respect to physical activity. The mean composite score in the LOD group was 5.9 ±2.4 and in control group was 5.7 ± 2.5. Comparison for individual items that measured physical activity based on the number of hours per day and also the number of activities also showed no significant difference (Table 6).
  46. 46. 40 Table 6 Comparison of individual items for physical activity Depression** control P Value* Exercice 0.6± 1.6 1.0± 1.9 .193 House Work 2.8± 2.3 2.8± 2.0 .940 Hours Of Activity 2.6± 0.6 2.4± 0.9 .208 * Mann- Whitney test ** Mean scores ± Standard Deviation Depressive subjects felt they were very physically active before the onset of the current episode of depression and this was found statistically significant when compared with control group (Fig 2) Fig 2 Comparison of self reported opinion on physical activity * 0 5 10 15 20 25 30 35 40 very active moderate not active Depression Control X axis= level of activity (very active, moderately active, not active). Y axis= no. of subjects.* chi square test. (p = 0.043)
  47. 47. 41 Socialization Socialization was scored on the distance of close relatives from home and the frequency of interaction with friends and children. There was no significant difference (p= 0.82) between the two groups with respect to socialization when compared on the composite scores. The mean composite score for LOD Group was 11.7 ±4.6 and for control group was 11.4 ±4.3 However when individual items were compared it was found that the depressive group significantly chatted less with friends/peers (p=0.024) and more with their children when compared with the control group (p=0.001).(Table 7) Table 7 Comparison of individual items for socialization Depression** Control P Value* Distance - Nearest Relative 2.2± 1.5 2.5± 1.3 .069 Distance- Sister Brother 2.8± 1.8 2.5± 1.3 .667 Distance- Nearest Child 1.8± 1.5 1.6 ±1.8 .283 Chat with Children 2.6± 6.4 1.5± 1.8 .011 Chat with Friend 1.5± 1.0 2.1± 1.8 .027 Chat with Neighbour 1.6± 1.0 1.7± 0.9 .458 * Mann- Whitney U test ** Mean scores ± Standard Deviation Substance Use The subjects were assessed about whether they followed religious activities like ―pooja‖at home or visiting temple or other place of worship. The groups differed (p= 0.052) with respect to religious activities reported. Less percentage n=34 (74.0%) of subjects in the depressive group followed religious activities compared to control group n= 42 (91.3%).
  48. 48. 42 Leisure Activity and Hobbies Leisure activities were measured as scores that measured the number of leisure activities reported. There was no significant difference (p= 0.706) between the groups with respect to leisure activities. The mean score for LOD group was 2.2± 1.4 and for the control group was 2.3± 1.1. There was no significant difference (p = 0.662) between groups on tobacco use (15 in depression group and 17 in control group). Very few had a history of alcohol use in either group (4 in LOD and 5 in control group). Summary of Results 1. The study involves 92 subjects- 46 cases with Late Onset Depression (LOD) and 46 age, sex and education matched controls. 2. The cases and controls differed (P=.051) with respect to socio economic status. The control group had more number of subjects in the low socio-economic category. 3. The Groups did not differ with respect to Body Mass Index (BMI) or the Cumulative Illnesses Rating Scale Scores (CIRS-G). 4. There were significantly (p= 0.035) more subjects with vascular risk factors (HTN, DM or both) in the depressive group. 5. HDRS ranged widely (5 to 35) in the LOD group as many subjects were in remission. 6. Though there was higher percentage of vegetarians 22 (47.8%) in the LOD group compared to the controls 13(28.3%) this was not statistically significant (p=0.085) 7. The mean composite scores for dietary factors, physical activity, socialization and leisure activities did not differ significantly between the groups and substance use was found to be
  49. 49. 43 very low. On comparison of individual items it was found that groups differed significantly in the following items. a. LOD group was significantly taking more of dietary fiber (p<0.001) and dairy products (p=0.03). b. LOD group significantly chatted less with friends/peers (p=0.024) and more with their children when compared with the control group (p=0.001). 8. LOD subjects reported that they felt their diet was very healthy (p=.03) and that they were very active physically (p=.043) before the onset of depression and this was significant when compared with control group who felt they were only moderately healthy and active.
  50. 50. 44 DISCUSSION: Late Onset Depression (LOD) is different from Early Onset Depression (EOD) as discussed in the review and it is associated with various parameters which have to be separately studied rather than generalizing information from EOD. Among the various parameters, life-style and its ramifications on health and living seem to be very relevant in the elderly. Many studies in the Western countries have looked at it and hence formed the impetus for the current study in the Indian population. Life Style Factors of Diet, Physical Activity, Leisure Activities, Socialization and Substance Use were compared between LOD group and an age and gender matched control group. Causality was not presumed, but comparisons were made. A Descriptive and exploratory approach has been taken in this study. The clinic at which the study was conducted is a special clinic which serves mostly the population from southern India. Since it is a referral Institute, there were also referrals from the other parts of the country. Despite attempts by the investigator to match the two groups of study on age, sex, education and socioeconomic status cases and controls remained significantly different with respect to socio-economic status. The control group had more subjects in the low socio-economic status. The groups did not differ in age, gender or educational status. As it is known that Life Style Factors are often influenced by socioeconomic factors (50) the findings of this study need to repeated with more stringent matching of control group in future. The subjects were also largely from an urban background thus lending more heterogeneity in the lifestyle patterns especially diet. This might have resulted in greater individual differences thus blunting the inter group differences. The study is also a retrospective one with a cross- sectional design. Since most of the persons with LOD were on the road to
  51. 51. 45 recovery, it was possible to interview them about their Life Style Pattern before the onset of the episode. All the information gathered are pertaining to the period before the onset of the depressive illness. This information was also corroborated to some extent with the relative who accompanied the client. All the clients from the LOD groups were on antidepressants – often SSRI – either Escitalopram or Mirtazapine; rarely Venlafaxine. Body Mass Index is an objective indicator of health and indirectly life-style. The persons with LOD in this study did not differ in their BMI from that of the controls. Biological Functions especially appetite and food intake are affected in depression (54) with either low or high food intake which in turn could affect the body mass index. As discussed in the review, relation of BMI to depression is not clear though depressive individuals are prone for malnutrition probably because of decreased appetite or associated health morbidity. The sample studied did not show signs of malnutrition. This aspect need to be further explored especially in view of the conflicting reports as to whether higher BMI is protective in depression. There was no difference between the groups in the five broad categories of life style factors. Interesting differences emerged when individual items were scrutinized and compared. This is discussed below. Diet There was no difference in the dietary intake between the two groups. BMI not being different between the two groups corroborated this. A pervious study (72) also did not find differences in dietary factors between LOD men and controls. However it was found in the present study that depressed subjects were significantly taking more carbohydrate with fiber and diary products than controls. This difference was perceived to be a reflection of the dietary preference between the two groups – there were more vegetarians among the LOD
  52. 52. 46 group (48%) than the control group (28%) though the difference was not statistically significant (P= 0.08). Diary products are considered vegetarian in India and used as an important source of protein by vegetarians. Vegetarian diets are considered to be deficient in Vitamin B12 and Folic Acid which are associated with depression (66). But a study in adult population reported that vegetarian diet is not associated with depression (76). The lesser consumption of dairy products in the control group may also be explained by more percentage of lower-socioeconomic status subjects indirectly reflecting their purchasing power. Interestingly the LOD opined that their diet was better before the onset of their depression (Similar opinion voiced for physical activity also – see below). This may be due to recall bias of the elderly who is recovering from depression who perceives as the pre-depression days as being ‗golden‘ in comparison to the depressed period. This study needs to be extended further if definite conclusions have to be drawn regarding dietary habits including fiber, dairy products among others. Socialization Depressed subjects socialized less with their friends, but more with their own children. Despite other research affirming the relationship between decreased socialization and depression in the elderly (100) this finding probably needs to be understood in a varying socio cultural context. Currently a significant proportion of the Indian elderly continue to live in extended families especially the ‗young –old‘ (50 – 65 years) with married or unmarried children. In this study too majority of the subjects across the group lived with their children in the same house or within one mile as. The majority of the subjects in both groups also reported satisfaction with the help and support they got from close friends. However the LOD group reported significant history of less interaction with their friends and
  53. 53. 47 peers and more interaction with their children. This probably has resulted from the pattern of lesser interaction with peers and hence exaggerated interaction with children compared to the control group who reported probably equal socialization with both peers and family members. The above is only a hypothesis and needs to be validated further as one study from India report that ‗loneliness‘ may be more related to depression in the elderly than socialization (102). Interactions with peers/people outside the family circle could provide opportunities for mutual disclosures with the same age peers, facilitation in problem solving as well as positive distractions from interpersonal/other issues at home. More over content of sharing and quality of interactions are important variables than not just the frequency of interactions and this aspect was not specifically explored in this study. As the specific family structure was not explored this study could not corroborate a previous Indian study (42) which had reported that functional disorders were more common in elderly living in nuclear family or living alone compared to joint family. Participation in religious activities whether at home or outside was assessed as part of social activities and it was found that the depressive group had engaged in significantly less religious activities. This study assessed practice of religious activities as either ceremonial prayer at home or visits to place of worship. Lesser involvement in religious activities in the LOD may indirectly also reflect the lesser interaction patterns outside their home. This might be possible because accessibility of social connections is considered one of the mechanism through which religious participation may serve as a protective mechanism for health outcome. This result seems to support previous research which seems to suggest a positive effect of religious activities in protecting from depression (104,105).
  54. 54. 48 Physical Activity and Exercise: The depressive group subjectively reported more physical activity than control group. How ever when the same was quantified as ―number of hours of activity‖ there was no difference between the two groups. It may be due to recall bias of the depressed individuals when asked to report on their level of physical activity before they were depressed. As many of the subjects studied were in the ―young-old‖ (<65yrs) category they were involving themselves in heavy occupational physical activity especially those who were involved in farming. Many women also reported heavy house old occupational activities like washing clothes, cleaning etc. However this study did not assess them quantitatively in metabolic equivalents as done in some other studies. There is also a need to assess physical activities qualitatively as whether part of occupation or leisure as in some other studies (90) that have tried to distinguish the two with differential benefits. Leisure Activities and Hobbies: There was no difference in the types and numbers of leisure activities between the two study groups. Leisure activities and hobbies were assessed as the number of activities reported. There is a need to review the items in the tool in future work to see associations as some of the other research have combined physical activities and leisure (90, 93). There is also need to better understand leisure activities in culturally diverse elderly population (114). Substance Use: Despite detailed interviewing there were less number of elderly in both the groups who were using alcohol. Tobacco was slightly more and there was no difference between the two groups. Unlike the West, the current Indian elderly belong to the era where alcohol and tobacco are a ‗social taboo and hence the low prevalence of substance use and probably the lack of significant difference between the groups.
  55. 55. 49 In summary this study explored the life-style pattern in a sample of elderly Indian population and its influence on the genesis of depression. It is a retrospective study in elderly population who developed depression compared with and age, sex and educational status matched healthy controls. The life style patterns did not differ much between the groups studied. When individual items were compared there appeared significant differences which require elaboration in further studies.
  56. 56. 50 CONCLUSION This cross sectional study on Lifestyle Factors in Late Onset Depression (LOD) did not find significant difference between elderly with LOD and age, sex and education matched controls. However in this study there were certain interesting findings in relation to life-style and LOD in the Indian socio-cultural context. Depressed elderly consumed more dietary fiber and diary products. They perceived themselves being more physically active and following healthier diet before the onset of depression. They socialized less with their peers, but seemed to interact more with family, probably as a function of living with offspring. They reported significantly less religious practices than control group. Substance use was observed to be generally low. LIMITATIONS 1. For want of an available questionnaire that is applicable in Indian context life style questionnaire was devised based on available questionnaires after consultation with experts including statistician and nutritionist. 2. The questionnaire needs to be further fine tuned to include the dimensional aspects of leisure activities which have been used in studies done in dementia. 3. Both the study sample and control sample were derived form urban population with heterogeneous dietary patterns. This probably blunted the differences between the groups.
  57. 57. 51 FUTURE DIRECTIONS Further research both in standardization of the tool and also identification of specific life- style factors in LOD in India need to be carried out. Longitudinal studies need to be carried out with larger samples in more homogenous population to better understand the effects of life-style patters in late onset depression. Studies that can look at serum levels of fatty acids can be more informative about the influence of specific nutrients that can influence depression. The specific role of vegetarian diet and depression needs to be explored in a larger sample. Further exploration into the family structure and the specifics of social interaction patterns need to be studied in relation to geriatric depression. IMPLICATIONS OF THIS STUDY. Life-style factors are modifiable factors that influence health outcomes and present a window of opportunity to intervene for primordial prevention of diseases. As has been demonstrated for various physical illnesses if the beneficial effects of better life style could also be proved for mental health, public at large can be educated regarding positive changes in their life pattern. Significant differences between the depressed elderly and the matched controls did not emerge on several life style variables examined. However, the data highlighted interesting differences on a few items pertaining to dietary pattern and socialization. The study findings in general and these observations in particular have generated several hypotheses that need to be critically examined through further research.
  58. 58. 52 SUMMARY (ABSTRACT) Introduction. The association of lifestyle factors and Late Onset Depression (LOD) was studied in a treatment seeking elderly population in India. Method Treatment seeking population with LOD (n=46) and controls matched for age, sex and education was cross-sectionally assessed for lifestyle pattern. Depression was diagnosed based on DSM-IV criteria and HDRS was used for assessing severity of depression. Depressed group reported about their lifestyle prior to onset of depressive disorder. Lifestyle was assessed on five parameters namely diet, physical activity/exercise, leisure activities, Socialization, alcohol and tobacco use. Result The mean composite scores for dietary factors, physical activity, socialization and leisure activities did not differ significantly between the groups and substance use was found to be low. On comparison of individual items it was found that the LOD group was significantly taking more of dietary fiber (p<0.001) and dairy products (p=0.03). LOD group also chatted significantly less with friends/peers (p=0.024) and more with their children when compared with the control group (p=0.001). Less percentage n=34 (74.0%) of subjects in the depressive group followed religious activities compared to control group n= 42 (91.3%) (p=0.052). Conclusion This cross sectional study on Lifestyle Factors in Late Onset Depression (LOD) did not find significant difference between elderly with LOD and age, sex and education matched controls. However on comparison of individual items LOD group consumed more dietary fiber and diary products. They socialized less with their peers, but seemed to interact more with family, probably as a function of living with offspring. They reported significantly less religious practices than control group. Substance use was observed to be generally low. These findings need further elaboration in larger sample.
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