1. HLN004 Chronic Conditions
Prevention and Management
Lecture 2
Chronic Conditions –
burden, determinants and risk factors
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2. Hello!!
Dr Ignacio Correa-Velez
Senior Lecturer and Public Health Discipline
Coordinator
School of Public Health & Social Work, QUT
ignacio.correavelez@qut.edu.au
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3. Outline
What are chronic conditions?
Chronic conditions continuum
Global burden of chronic conditions – GBD study
2010
Determinants of chronic conditions
Indigenous Australians
Professional practice – Addressing risk factors
Australian National Health Survey 2007-08
GBD study 2010
Co-morbidities
Multidisciplinary? Interdisciplinary?
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4. What are chronic conditions?
Health conditions that:
Have complex and multiple causes
Usually have gradual onset (and may have acute
stages)
Occur across the life cycle... but more prevalent as
people age
Compromise quality of life
Are long term and often persistent... Gradual
deterioration of health
Are leading cause of premature death
Can be prevented
Impact heavily on medical services
4 (National Health Priority Action Council, 2006)
7. Measuring Burden of Disease
What is disease burden?
Common measures of disease burden:
Prevalence… AT A SPECIFIC TIME (current
burden)
Incidence… NEW CASES DURING A PERIOD OF
TIME (current risk)
Cause specific mortality rates
Disability-adjusted life years (DALYs) = Years of life
lost due to premature mortality (YLL) + years of
productive life lost due to illness and disability (YLD)
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8. Global burden of chronic conditions
GBD 2010 Key findings
Positives Negatives
Life expectancy for 52.8 million deaths in
2010 (46.5 m in 1990)
males and females is 8 million deaths from
increasing cancer (1/3 more than
1990)
Substantial progress 1 in 4 deaths from heart
in preventing disease or stroke
premature deaths 1.3 million deaths from
diabetes
from heart disease High blood pressure is the
and cancer biggest risk
factor, followed by
tobacco, alcohol and poor
diet
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Disability from disease
14. Comparing ranking of leading chronic conditions as
causes of DALYs, 2010 (GBD 2010, Murray et al)
Cause Global Australasi Oceania Southeas Western
a t Asia Europe
Ischaemic heart 1 2 6 3 2
disease
Cerebrovascular 3 5 8 11 3
disease
Low back pain 6 1 14 7 1
COPD 9 3 18 9 7
Major depressive 11 4 12 6 4
disorder
Diabetes mellitus 14 14 2 10 10
Iron-deficiency 15 36 21 14 84
anaemia
Congenital 17 27 17 16 15
anomalies
Neck pain 21 10 35 25 8
Trachea, 22 8 58 26 5
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bronchus & lung
15. Reducing the global burden of
chronic conditions
WHO: Global Non-communicable Disease Network
(2009)
http://youtu.be/VCfyylZdmG0
WHO: Unite in the fight against non-communicable
diseases (2011)
http://youtu.be/AvwX1m4LR4w
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18. Upstream? Downstream?
In 1974, John McKinlay, a physician, recounted this story as told to a
friend, at the American Heart Association conference in Seattle
Washington.
“You know” he said “sometimes it feels like this. There I am standing by the
shore of a swiftly flowing river and I hear a cry from a drowning man. So I jump
in the river, put my arms around him, pull him to shore and apply artificial
respiration.
Just when he begins to breathe, there is another cry for help. So I jump in the
river, reach him, pull him to shore and apply artificial respiration, and then just
as he begins to breathe, there is another cry for help.
So back in the river again, reaching, pulling, applying, breathing and then
another yell. Again and again, without end, goes the sequence.
You know, I am so busy jumping in, pulling them to shore, applying artificial
18 respiration that I have no time to see who the hell is upstream pushing them all
in!
19. Health and wealth over time: The
world in four minutes
http://www.gapminder.org/videos/200-years-that-
changed-the-world-bbc/
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20. Indigenous Australians
Poorest health status within the Australian
population
Lower life expectancy (12 years lower for males
and 10 years lower for females)
80% mortality gap between indigenous and non-
indigenous Australians aged 35-74 years is due
to chronic health conditions
Greatest contribution to mortality gap:
Diseases of the circulatory system (38%)
Endocrine, nutritional and metabolic diseases (14%)
Diseases of the digestive system (14%)
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21. Leading specific disease groups contributing to the mortality
gap, persons aged 35-74 years (AIHW, 2011)
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32. GBD 2010: Risk factors
In 2010 the three leading risk factors for global disease
burden were:
High blood pressure: 7% of global DALYs; 9.4 million deaths
Tobacco smoking (including second hand smoke): 6.3% of
global DALYs; 6.3 million deaths
Alcohol use: 5.5% global DALYs; 4.9 million deaths
Regional differences:
Much of the world: obesity and high body mass index
Sub-Saharan Africa: underweight
Dietary risk factors and physical inactivity collectively
accounted for 10% of global DALYs
Most prominent dietary risks: low fruit and high sodium
High body mass index has increased globally: leading
risk in Australasia and southern Latin America; ranks high
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in other high-income regions, and also in North
Africa, Middle East and Oceania
33. Global risk factor ranks for all ages and sexes
combined in 1990 and 2010 (GBD 2010, Lim et al)
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34. Comparing ranking of risk factors for chronic conditions, 2010 (GBD
2010, Lim et al)
Risk factor Global Australasi Oceania Southea Western
a st Asia Europe
High blood pressure 1 3 6 1 2
Tobacco smoking 2 2 3 2 1
(inc SHS)
Alcohol use 3 4 5 6 4
Diet low in fruits 5 7 9 4 7
High body mass 6 1 2 9 3
index
High fasting plasma 7 6 1 5 6
glucose
Physical inactivity 10 5 7 8 5
Diet high in sodium 11 11 16 7 10
Diet low in nuts and 12 8 13 15 9
seeds
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Iron deficiency 13 21 11 12 32
35. GBD 2010 and risk factors: Policy implications
Increasing burden from high blood pressure, high
body mass index and high blood sugar
Key role: dietary risk factors and physical inactivity
Policies that encourage or facilitate lifestyle changes
(balanced diet and increased physical activity)
Despite efforts, tobacco smoking remains a serious
issue (little change): decrease in high income
countries but increase in low and middle income
countries
High blood pressure: dietary interventions (low salt)
but also improve primary health care interventions to
detect and treat
35 Regional differences require regional tailoring of
36. Co-morbidities
Complex interaction between specific conditions
and shared risk factors
Increased mortality
Decline in health outcomes
Increase use of health care resources
Greater prevalence and impact among particular
populations:
Aged
Indigenous Australians
Survivors of torture and trauma
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37. Chronic health conditions and mental
health
Ischaemic heart disease: 25-30% depression;
independent factor for poor prognosis
Depression: independent risk factor for the development
of cardiovascular disease and increased cardiac
morbidity and mortality
COPD: higher prevalence of depression and anxiety;
increased mortality, decreased functional
status, decreased quality of life
Mental illness:
Higher rates of chronic health conditions related to
behavioural factors such as smoking, alcohol and drug
abuse, obesity and poor diet
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Higher mortality and hospitalisation rates for all major
conditions
38. Chronic conditions care approach
Multidisciplinary Interdisciplinary
Hierarchical (highest- Horizontal: leadership
ranking team member) functions are shared
Independent goals and Common goals and
own recommendations prevention/care plans
Multi-discipline
assessment (but not Comprehensive/team
integrated) assessment
(biopsychosocial)
Face-to-face
Unidirectional meetings and patient
communication team conferences
38 (letters, emails, phone
39. In summary…
Global burden of chronic disease continues to increase
Overall, the GBD 2010 has shown a broad shift from
communicable, maternal, neonatal and nutritional causes of
death towards non-communicable (Chronic) health conditions
Regional differences (sub-Saharan Africa)
Leading causes of death: Ischaemic heart
disease, stroke, COPD
Leading chronic conditions as measured by DALYs: Ischaemic
heart disease, stroke, low back pain
Leading risk factors: high blood pressure, smoking, alcohol, diet
low in fruit, high body mass index, high blood sugar
Key role of co-morbidities (mental health in particular)
Approach:
Upstream, midstream and downstream determinants of health
Continuum of care
Interdisciplinary
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Some communicable conditions can also be chronic (e.g. HIV/AIDS, tuberculosis)In this unit when we talk about chronic conditions we refer to non-communicable conditions
As described in Module 1, the course of chronic conditions can be viewed as a continuum from the upstream social and environmental determinants (that can impact an individual since conception and childhood), to individual health risk behaviours (e.g. smoking, poor diet, physical inactivity) – these risk behaviours in turn can lead to chronic health problems (high blood pressure, obesity, high blood cholesterol), which over time increase the risk of developing chronic diseases (heart disease, cancer, diabetes, etc). These chronic diseases lead to impairment, disability and finally death.This chronic conditions continuum is also reflected in the levels of disease prevention (including health promotion, 1ry, 2ry and 3ry prevention) which will be discussed in more detail in Module 3, and also in the levels of health care provision (1ry, 2ry and 3ry care).
What is disease burden? It is the impact of a disease or a group of diseases on a population in terms of mortality, morbidity and disabilityHow can we measure disease burden? The most common measures are:Prevalence: “number of affected persons present in the population AT A SPECIFIC TIME divided by the number of persons in the population at that timeIncidence: “number of NEW CASES of a condition that occur during a specified period of time in a population at risk of developing the conditionWhereas PREVALENCE measures the current burden of the condition in a population, INCIDENCE reflects the current risk of developing the condition in those not currently affected by the condition. For example, if we have 100 children in school and we have measured that over the last year 10 children were diagnosed with asthma, the risk of developing asthma in those children without the condition is 10%Prevalence and incidence are related: as incidence increases, prevalence also increasesDisease burden can also be measured using cause specific mortality rates which are an estimate of the proportion of a population that dies during a specified period as a result of a specific health condition. For example, in 2010 the (age standardised) mortality rate worldwide for non-communicable (chronic) conditions was 520.4 persons per 100,000 population; for ischaemic heart disease was 105.7 persons per 100,000 population; for all types of cancer was 121.4 persons per 100,000 population.Prevalence, incidence and cause specific mortality rates tell us how common a condition occurs within a population and its contribution to overall mortality within that population BUT fail to capture the contribution (the true impact) of a specific condition to morbidity and disability within that population. That’s why the most commonly used measure today is the DISABILITY-ADJUSTED LIFE YEARS (DALYs) which is defined as the sum of the years of life lost (YLL) due to premature mortality and the years of productive life lost due to illness or disability (YLD) – ONE DALY REPRESENTS ONE LOST YEAR OF HEALTHY LIFEIn essence, disability-adjusted life years measure the difference between current health status and an ideal situation where everyone lives into old age (standard life expectancy), free of disease and disabilityFor example, in 2010, the DALYs for non-communicable (chronic) conditions worldwide were 19,502 years per 100,000 population; for ischaemic heart disease were 1,884 years per 100,000 population; and for all cancers were 2,736 years per 100,000 population.
GBD 2010: 486 scientists from 302 institutions across 50 countriesGBD 1990: 107 conditions and 10 risk factors were assessedGBD 2010: 235 causes of death and 67 risk factors
15-49 years: Females = 3.5 million deaths; Males = 5.7 million deathsAmong FEMALES: leading cause was HIV/AIDS, followed by cardiovascular disease, maternal disorders, suicide, tuberculosis, breast and cervical cancer, and digestive diseases and cirrhosis. The top seven causes accounted for half of the deaths of women in these age groups.For MALES in this age group, the leading causes of death were cardiovascular diseases, road traffic injuries, and HIV/AIDS, with other major causes including suicide and interpersonal violence.
This FIGURE shows the top 25 causes of death in the world ranked in 1990 and 2010 with arrows connecting the causes between the two periods. The right hand side column shows the % of change in number of deaths between 1990 and 2010Although the top four causes of death in 1990 remain the top four in 2010, the change in numbers of deaths is noteworthy, with ischaemic heart disease and stroke increasing by 26—35% over the interval, but COPD declining by 7%. Lung cancer increased from the 8th cause to the 5th cause in the two decades because of a 48% increase in absolute number of deaths.Large increases in absolute number of deaths and their relative importance can be seen for diabetes, liver cancer, and chronic kidney disease. Each of these causes has increased by more than 50% over the two decades.Overall, the GBD 2010 has shown a broad shift from communicable, maternal, neonatal and nutritional causes of death towards non-communicable (Chronic) health conditions
This slideprovides a comparison of the top 25 causes of years of life lost (YLLs due to premature mortality) for both sexes combined, which gives an even more meaningful perspective on priorities for disease control than a simple ranking of causes of death according to the numbers of deaths from each cause. The leading cause of YLLs globally was lower respiratory infections in 1990 and ischaemic heart disease in 2010; in this period, the total number of YLLs increased 28% for ischaemic heart disease. More generally, a number of communicable, maternal, neonatal, and nutritional causes declined in both absolute terms and in relative importance as causes of YLLs.Conversely, several non-communicable diseases increased in importance over the two decades: ischaemic heart disease, stroke, lung cancer, cirrhosis, diabetes, liver cancer, and chronic kidney disease particularly, although COPD and congenital causes have declined in rankings of YLLs
When we look at years lived with disability (YLDs) worlwide, we can see clearly than chronic (non-communicable) conditions were the most common cause of years lived with disability in both 1990 and 2010; 21 of the 25 leading causes are chronic conditions in 2010, up from 19 of the 25 most common in 1990. The four leading causes in 2010 were also the four leading causes in 1990: low back pain, major depressive disorder, iron-deficiency anaemia, and neck pain.
Now, the previous 3 graphs showed global death ranks, global years of life lost (YLLs), and global years lived with disability for the top 25 causes.This graph, compares the Global DALY ranks for the top 25 causes between 1990 and 2010.Similar to the previous YLLs graph, the analysis of DALYs show that most of the chronic (non-communicable) conditions are rising in the rank list and most but not all communicable, maternal, neonatal, and nutritional disorders are declining (EPIDEMIOLOGICAL TRANSITION OF DISEASE). Among chronic conditions, only Chronic Obstructive Pulmonary Disease (COPD) and congenital anomalies have declined. We can see in the graph that lung cancer has increased from 24th to 22nd between 1990 and 2010 but COPD has decreased from 6th to 9th and this is driven by the reduction of other determinants of COPD such as household air pollution in India and China, despite increasing exposure to tobacco in these countries.
When we compare the rankings of leading chronic conditions causing DALYs in 2010 we can see the significant burden of disease due to chronic conditions not only in high income countries in Australasia (Australia and New Zealand) and Western Europe but also in low to middle income countriesThose conditions in the top ten are highlighted in blue.IN SUMMARY, data from the recently published GBD 2010 study shows that the global disease burden has continued to move away from communicable diseases to chronic (non-communicable) conditions, and from premature death to years lived with disability (we are living longer but those years are impacted by ill health and disability). We have to acknowledged however variations in GDB across regions (e.g. in sub-Saharan many communicable, maternal, neonatal and nutritional disorders remain the dominants causes of disease burden.We also see from the data an increasing burden from mental and behavioural disorders, musculoskeletal disorders, and diabetes and therefore health systems worldwide must prepare to meet these new challenges.
What global strategies are being implemented to reduce the global burden of chronic conditions?These 2 videos describe some of the global strategies being implemented by the WHO to assist governments throughout the world to reduce the burden of chronic conditions.Let’s watch the videos (about 6.5 minutes each)
Let’s focus now on the determinants of chronic health conditions. All those factors that influence how healthy we are, are collectively known as determinants of health. Those determinants than can influence our health in a positive way are called PROTECTIVE FACTORS (e.g. healthy eating, good levels of physical activity, having a healthy body weight, etc) – they help us to maintain our health or support an effective management of a health condition.Determinants that affect our health in a negative way are known as RISK FACTORS. These risk factors increase the likelihood of developing a health condition or may hinder the adequate management of a chronic condition.
We can perceive health determinants as part of broad causal pathways that affect health. This figure presents a conceptual framework adopted by the AIHW of the pathways involved in the health and functioning of individuals and the population.Looking left to right, the framework is divided into four main components that flow from ‘upstream’ (background)factors, which include culture, policies and environment, through to the more immediate (downstream) factors, suchas body weight and blood pressure. Although the pathways in the framework are presented as flowing from left to right, it should be noted that sometimes these can happen in reverse. For example, illness or injury can influence a person’s health behaviour, such as their ability to do physical activity.Non-modifiable factors of individual physical and psychological make-up, such as age and intergenerationalinfluences, underpin these pathways.
This is a good story that allow us to see the importance of considering the upstream determinants of health!!Too often in health care we look only at the most immediate determinants of chronic conditions such as body weight or blood pressure, or at the individual behaviours such as tobacco use of poor diet, but we fail to see the importance of upstream factors such as lack of education, unemployment and poverty. These upstream factors can seriously impact on a person’s health behaviours leading to poor diet, tobacco use, obesity and high blood pressure which in turn can lead to cardiovascular disease and ultimately disability or death. We will see in the other modules of the unit that addressing these upstream factors play an important role in the prevention of chronic conditions.
Let’s watch this very interesting video by Hans Rosling, Professor of International Health at Karolinska Institute in Sweden. The video shows the important link between upstream determinants (such as wealth) and health across the world.
The health status of Indigenous Australians is a clear example of the impact of the broader, upstream, determinants of healthIndigenous Australians have the poorest health status of any population group in Australia…
This graph shows the leading specific disease groups contributing to the mortality gap between Indigenous and non-Indigenous Australians.To the left we see the Potential Years of Life Lost gap per 10,000 population (Bars)To the right, you can see the cummulative contribution percentage of each of the health conditions (line)So we can see that over 60% of the mortality gap results from six specific chronic conditions: ischaemic heart disease (first bar), diabetes, diseases of the liver, other heart diseases, chronic lower respiratory conditions, and cerebrovascular conditions.
The reasons why the health status of Indigenous Australians remains poor are complex. It includes historical and political factors, social and economic disadvantage, housing, community safety and security, justice, education, culture, language, employment and income, locality, community development. For instance, Indigenous Australians report having lower incomes, higher rates of unemployment, lower educational attainment, and more overcrowded households than other Australians These factors may also apply to disadvantage communities across the world.Addressing the broader determinants of health – not only the downstream factors but most importantly the upstream and midstream factors, is vital to closing the gap between indigenous and non-indigenous Australians.
Although every single member of a society plays a role in addressing the broader social determinants of health (or upstream factors) that impact on disadvantage communities (e.g. social justice, human rights, safe neighbourhoods, volunteering, assisting others, respecting diversity, etc), in your professional practice it’s more likely that you will be involved in addressing the modifiable risk factors for chronic conditions (midstream and downstream factors) such as health behaviours and biomedical factors.Let’s have a look at some of the modifiable risk factors for selected chronic conditions
This table which is also in the Module 1 document, shows the relationship between selected chronic conditions and modifiable risk factors. The table reflects data that was collected by the 2007-08 Australian National Health Survey (ABS).We can see that tobacco smoking, physical inactivity and poor diet are all linked to most major chronic conditions. This has implications for our professional practice, because a single chronic condition is often the result of multiple risk factors and therefore we need a comprehensive, interdisciplinary approach that addresses multiple risk factors in order to prevent and manage chronic conditions.
The ALCOHOL risk levels have been defined by the NHMRC as:Low risk: Males – 50 mLs or less per day; Females – 25 mLs or lessRisky: Males – more than 50 up to 75 mLs; Females – more than 25 up to 50 mLsHigh risk: Males – more than 75 mLs; Females – more than 50 mLs per dayONE STANDARD DRINK CONTAINS 12.5 mLs of alcoholPHYSICAL ACTIVITY: The National Physical Activity Guidelines for Australia (1999) recommend thatto achieve health benefit, a person should participate in 30 minutes of at least moderate-intensity physical activity onmost days of the week. For the purposes of calculating sufficient activity, this is interpreted as 30 minutes on at least5 days of the week (a total of 150 minutes per week)The type of milk consumed is used as a proxy indicator for saturated fat intake. This has shown to be a valid indicator of energy obtained from total fat and saturated fat.A waist-to-hip ratio (WHR) is calculated by dividing a person’s waist measurement by their hip measurement. AWHR of 1.0 or more for males or 0.85 or more for women indicates excess weight.The WHO defines high blood pressure as:• systolic blood pressure of 140mmHg or more• diastolic blood pressure of 90 mmHg or more• receiving medication for high blood pressure.
The same National Health Survey has shown that about 99% of the population have at least one common risk factor; and about one third of the population have at least three of these risk factors for chronic conditions.We can see also in the table that the distribution of numbers of risk factors was similar for males and females, with slightly more males having five or more risk factors (16.7% of males compared with 11.1% of females). It’s well known that the more risk factors a person has, the greater the risk of developing a chronic condition.
The number of risk factors also varies across socio-economic status and geographic location. In this graph we can see that those in more disadvantaged areas have more risk factors. 46% of those living in the most disadvantaged areas in Australia report having four or more risk factors compared with 27% of people living in least disadvantaged areas.The analysis by geographic location (which is not shown here) found that those living in Major Cities report smaller number of risk factors compared with those living in regional and remote areas.
The National Health Survey also found differences in the numbers of risk factors present by the type of chronic condition. For mostconditions, more people with that condition are likely to report a higher number of risk factors than none, one or two.For example, of those who report having arthritis, 23% have six or more risk factors compared with 16% who have norisk factors.
The combination of risk factors can lead to either earlier development of a condition, to an increased need for management or burden from a condition, or to mortality. However, it’s difficult to measure the exact effect of multiple risk factors, as they often mediate through other factors as shown in this figure:Excess body weight can either directly lead to Ischaemic heart disease or can cause increased blood pressure which in turn leads to ischaemic heart disease. The effect of excess salt intake can also be mediated by increased blood pressure.
According to the National Health Survey 2007-08, 7.9% of males reported a combination of:F (insufficient fruit consumption)V (insufficient vegetable consumption)M (Usual consumption of whole milk)PA (insufficient physical activity)6.9% of males reported V (insufficient vegetable consumption) compared with 8.9% of females8% of females reported insufficient fruit consumption combined with insufficient physical activity.
The national health survey 2007-08 has given us excellent evidence of the prevalence of common risk factors in the Australian population and their relationship with common chronic conditions.Let’s have a look now at the most recent international data on risk factors reported by the GBD study 2010.The main findings of the GBD study 2010 in terms of risk factors are…
In 1990, the leading risks were:childhood underweight (7·9% of global DALYs), household air pollution from solid fuels (7·0%), tobacco smoking including second-hand smoke (6·1%), High blood pressure (5·5%), and suboptimal breast feeding (4·4%).We can see in the table that, apart from house hold air pollution, which is a significant contributor to childhood lower respiratory tractinfections, the five leading risk factors in 2010 (high blood pressure, tobacco smoking including second hand smoke, alcohol use, household air pollution, and diets low in fruits) are mainly causes of adult chronic conditions, especially cardiovascular diseases and cancers.We can also see in this graph that most risk factors associated with chronic conditions increased between 1990 and 2010 while those risk factors that largely or exclusively cause communicable diseases in children have decreased
How Australasia compares with other regions?
The burden of chronic conditions is compounded by the co-existence of other health conditions or co-morbidities.
Multidisciplinary:Hierarchically organised: one or two health care professionals directing the services of other team members; traditionally led by the highest-ranking team member
