This document summarizes a workshop convened by the National Institutes of Health and Centers for Disease Control and Prevention to discuss the feasibility of conducting a randomized clinical trial to estimate the long-term health effects of intentional weight loss in obese individuals. While short-term studies show weight loss reduces disease risk factors, little is known about long-term health outcomes. Observational studies have limitations and results are inconclusive. Workshop participants agreed a well-designed randomized trial could provide clearer answers about long-term health risks and benefits of weight loss, informing clinical practice and policy.
Cognitive Behavior Therapy combined with Physical Exercise for Adults with Ch...BERNARD Paquito
Cognitive Behavior Therapy combined with Physical Exercise for Adults with Chronic Diseases Systematic Review and Meta-Analysis
OPEN ACCESS https://archipel.uqam.ca/10922/1/Bernard%202018%20CBTEx.pdf
Cognitive Behavior Therapy combined with Physical Exercise for Adults with Ch...BERNARD Paquito
Cognitive Behavior Therapy combined with Physical Exercise for Adults with Chronic Diseases Systematic Review and Meta-Analysis
OPEN ACCESS https://archipel.uqam.ca/10922/1/Bernard%202018%20CBTEx.pdf
Falls are the leading cause of fatal and nonfatal injuries in the older adult population. After a fall, many individuals become fearful that they will fall, and reduce their participation in activities. This reduction in activities, called constraints, cascades into poorer physical, emotional, and cognitive health. In this study, older adults participated in a Hatha yoga intervention led by a yoga therapist, which was designed to determine if this was feasible and acceptable in older adults, and to determine if yoga helped to reduce leisure constraints. Leisure constraints were reduced over the 12-week period, and more dramatically for individuals who had fallen in the past six-months, compared to those who had not fallen in the past six-months. The data reported here also support that the intervention was feasible and acceptable. Implications for future research and practice are included.
Population Health Management Telehealth Intervention Medical Research Treatin...CrimsonpublishersMedical
Population Health Management Telehealth Intervention Medical Research Treating Comorbid Clinical Obesity and Depression in Geriatric Patients Part One: Review of Tele-Medicine Scientific Research by Robelyn A Garcia in International Journal of Medical Sciences
Cardiorespiratory Fitness, Health Outcomes, and Health Care Costs: The Case f...Matti Salakka 🐠
Physical inactivity is becoming a world-wide epidemic – and the consequences can be both costly and deadly. This was outlined by Dr. Jonathan Myers who, citing a range of studies and recent research results, was able to show hard-hitting data related to the correlation between fitness (or lack thereof) and poor health. Myers argues fitness may well be a better marker than traditional risk factors for CVD and all-cause mortality. Amongst the eye-opening findings presented to the audience was that, for the first time, global deaths-per-year due to physical inactivity are higher than for smoking.
Exercise is a subcategory of physical activity that is planned, structured, repetitive and purposeful with the objective of improving or maintaining one or more components of physical fitness.
Falls are the leading cause of fatal and nonfatal injuries in the older adult population. After a fall, many individuals become fearful that they will fall, and reduce their participation in activities. This reduction in activities, called constraints, cascades into poorer physical, emotional, and cognitive health. In this study, older adults participated in a Hatha yoga intervention led by a yoga therapist, which was designed to determine if this was feasible and acceptable in older adults, and to determine if yoga helped to reduce leisure constraints. Leisure constraints were reduced over the 12-week period, and more dramatically for individuals who had fallen in the past six-months, compared to those who had not fallen in the past six-months. The data reported here also support that the intervention was feasible and acceptable. Implications for future research and practice are included.
Population Health Management Telehealth Intervention Medical Research Treatin...CrimsonpublishersMedical
Population Health Management Telehealth Intervention Medical Research Treating Comorbid Clinical Obesity and Depression in Geriatric Patients Part One: Review of Tele-Medicine Scientific Research by Robelyn A Garcia in International Journal of Medical Sciences
Cardiorespiratory Fitness, Health Outcomes, and Health Care Costs: The Case f...Matti Salakka 🐠
Physical inactivity is becoming a world-wide epidemic – and the consequences can be both costly and deadly. This was outlined by Dr. Jonathan Myers who, citing a range of studies and recent research results, was able to show hard-hitting data related to the correlation between fitness (or lack thereof) and poor health. Myers argues fitness may well be a better marker than traditional risk factors for CVD and all-cause mortality. Amongst the eye-opening findings presented to the audience was that, for the first time, global deaths-per-year due to physical inactivity are higher than for smoking.
Exercise is a subcategory of physical activity that is planned, structured, repetitive and purposeful with the objective of improving or maintaining one or more components of physical fitness.
511vol. 14 • no. 5 American Journal of Lifestyle Medicine.docxstandfordabbot
511
vol. 14 • no. 5 American Journal of Lifestyle Medicine
AnAlytic
Abstract: There is overwhelming
evidence in the scientific and medical
literature that physical inactivity is a
major public health problem with a
wide array of harmful effects. Over 50%
of health status can be attributed to
unhealthy behaviors with smoking, diet,
and physical inactivity as the main
contributors. Exercise has been used
in both the treatment and prevention
of a variety of chronic conditions such
as heart disease, pulmonary disease,
diabetes, and obesity. While the
negative effects of physical inactivity
are widely known, there is a gap
between what physicians tell their
patients and exercise compliance.
Exercise is Medicine was established
in 2007 by the American College of
Sports Medicine to inform and educate
physicians and other health care
providers about exercise as well as
bridge the widening gap between health
care and health fitness. Physicians have
many competing demands at the point
of care, which often translates into
limited time spent counseling patients.
The consistent message from all health
care providers to their patients should
be to start or to continue a regular
exercise program. Exercise is Medicine
is a solution that enables physicians to
support their patients in implementing
exercise as part of their disease
prevention and treatment strategies.
Keywords: inactivity; exercise; vitals;
behaviors; referral
Physical inactivity underlies many
of the chronic conditions that
affect people worldwide, has an
astonishing array of harmful health
effects, and is associated with escalating
health care costs. For example, 7 cancers
have been linked to a physically inactive
lifestyle.1 Depression affects 17 million
Americans2 and has been directly linked
to insufficient physical activity.3
Alzheimer’s disease and related
dementias are increasing at a frightening
rate. By 2025, the number of people
aged 65 years and older with Alzheimer’s
disease is expected to reach 7.1 million
people. In the United States alone, more
than 30 million adults are estimated to
have diabetes,4 95% of whom have type
2 diabetes (T2DM). Considering that a
new case of diabetes is diagnosed every
21 seconds, it is no surprise that diabetes
is the most expensive disease in America,
coming in at a price tag of $327 billion
annually.5 Underlying the vast majority of
T2DM are unhealthy lifestyle behaviors
(poor nutrition and insufficient physical
activity leading to overweight and
obesity). In addition to T2DM, an
unhealthy lifestyle (including tobacco
use, excessive alcohol intake, poor sleep,
and stress) underlies prevalent and costly
chronic diseases (eg, heart disease and
cancer) leading to premature morbidity
and mortality.
While other determinants of health
(genetics, environment, and medical
care) influence health outcomes, by far
the most important factor contributing to
health outcomes is in.
REVIEW Open AccessWeight Science Evaluating the Evidence .docxjoellemurphey
REVIEW Open Access
Weight Science: Evaluating the Evidence for a
Paradigm Shift
Linda Bacon1*, Lucy Aphramor2,3
Abstract
Current guidelines recommend that “overweight” and “obese” individuals lose weight through engaging in lifestyle
modification involving diet, exercise and other behavior change. This approach reliably induces short term weight
loss, but the majority of individuals are unable to maintain weight loss over the long term and do not achieve the
putative benefits of improved morbidity and mortality. Concern has arisen that this weight focus is not only
ineffective at producing thinner, healthier bodies, but may also have unintended consequences, contributing to
food and body preoccupation, repeated cycles of weight loss and regain, distraction from other personal health
goals and wider health determinants, reduced self-esteem, eating disorders, other health decrement, and weight
stigmatization and discrimination. This concern has drawn increased attention to the ethical implications of
recommending treatment that may be ineffective or damaging. A growing trans-disciplinary movement called
Health at Every Size (HAES) challenges the value of promoting weight loss and dieting behavior and argues for a
shift in focus to weight-neutral outcomes. Randomized controlled clinical trials indicate that a HAES approach is
associated with statistically and clinically relevant improvements in physiological measures (e.g., blood pressure,
blood lipids), health behaviors (e.g., eating and activity habits, dietary quality), and psychosocial outcomes (such as
self-esteem and body image), and that HAES achieves these health outcomes more successfully than weight loss
treatment and without the contraindications associated with a weight focus. This paper evaluates the evidence
and rationale that justifies shifting the health care paradigm from a conventional weight focus to HAES.
Introduction
Concern regarding “overweight” and “obesity” is reflected
in a diverse range of policy measures aimed at helping
individuals reduce their body mass index (BMI)1. Despite
attention from the public health establishment, a private
weight loss industry estimated at $58.6 billion annually in
the United States [1], unprecedented levels of body dissa-
tisfaction [2] and repeated attempts to lose weight [3,4],
the majority of individuals are unable to maintain weight
loss over the long term and do not achieve the putative
benefits of improved morbidity and mortality [5].
Concern has arisen that this weight focused paradigm is
not only ineffective at producing thinner, healthier
bodies, but also damaging, contributing to food and body
preoccupation, repeated cycles of weight loss and regain,
distraction from other personal health goals and wider
health determinants, reduced self-esteem, eating disor-
ders, other health decrement, and weight stigmatization
and discrimination [6-8]. As evidence-based competen-
cies are more firmly embedded in health practitioner
standa ...
Cardiometabolic diseases (CMDs), such as hypertension, excess weight, obesity, diabetes (type-2), and vascular diseases are considered lifestyle diseases. In the last three decades, these diseases have reached epidemic proportions worldwide [1]. According to the results of a recent study published in the journal Circulation, adopting five low-risk lifestyle factors may be linked to longer life spans in Americans [2]. Metabolic diseases, which are lifestyle diseases are preventable.
Cardiorespiratory Fitness, Health Outcomes, and Health Care Costs: The Case f...Firstbeat Technologies
Physical inactivity is becoming a world-wide epidemic – and the consequences can be both costly and deadly. This was outlined by Dr. Jonathan Myers who, citing a range of studies and recent research results, was able to show hard-hitting data related to the correlation between fitness (or lack thereof) and poor health. Myers argues fitness may well be a better marker than traditional risk factors for CVD and all-cause mortality. Amongst the eye-opening findings presented to the audience was that, for the first time, global deaths-per-year due to physical inactivity are higher than for smoking.
American Heart Association Lifestyle Recommendations to Redu.docxSusanaFurman449
American Heart Association Lifestyle Recommendations to Reduce Obesity
Yuritza Medina
Chamberlain College of Nursing
NR709 Project and Practicum IV
Summer 2022
Abstract Past tense
The prevalence of obesity and sedentary lifestyle complications are increasing at alarming rates, representing a common but preventable cause of severe medical complications like diabetes, cardiovascular diseases, and early mortality. This common but chronic condition has been for a long time a public health concern and social determinant. The integrative review focused on how the American Heart Association (AHA) Diet and Lifestyle recommendations and the Fitbit app are used as innovative solutions to reduce obesity in adult patients. The Fitbit app offers a unique opportunity to enhance the efficacy of weight loss plans, as it is used to track activity, monitor steps, heart rate, energy expenditure, sleep, and sedentary behavior.
Research Methodology: A systematic review was conducted to identify research articles completed in the preceding 4-5 years centered on obesity care, diet, physical activity, activity trackers, and lifestyle implications. The databases searched were Chamberlain Library, PubMed, and CINHAL.
Results and Discussion: Initial searches yielded over 2000 articles, of which 45 were chosen and examined because they fit the integrative review's theme. The 15 papers most relevant to the PICOT question were studied in further detail and appraised using the Johns Hopkins Evidence Appraisal table. The studies reported positive physical activity outcomes. What were the key themes?
Conclusions and Further Recommendations:This systematic review supported the effectiveness of the AHA Diet and Lifestyle recommendations to prevent and reduce obesity, and clinical use is recommended. Fitbit app provides new ways to improve physical activity habits, and the easy availability of electronic devices may enhance their generalizability use.
Keywords: Obesity care; Obesity complications; Lifestyle recommendations; Obesity management; Physical activity intervention using Fitbit activity trackers.
Dedication
In dedication to my family for their steadfast support of this project; their cooperation means a lot to me. To my husband Armando, thank you for your love, understanding, and patience during this time. I credit my achievement to all of you for your unwavering love and belief in me.
Acknowledgments
First, I must acknowledge the help of all my professors from Chamberlain University, who inspired, encouraged, and supported me throughout the DNP program. My heartfelt thanks to my teammates, without whom I would never have completed this phase in my life. Their encouragement has had a significant influence on my strong determination during this trip.
Contents
American Heart Association Lifestyle Recommendations to Reduce Obesity 1
Abstract 2
Dedication 3
Acknowledgments 4
Introductio.
Dietary Lifestyle, Way of Life Practices and Corpulence: Towards Present Day Science by Alok Raghav, Aditi, Sneha Gupta, Pratibha Singh, Aman Nikhil, Saba Noor and Jamal Ahmad in Examines in Physical Medicine & Rehabilitation
A correlation study to determine the effect of diabetes self management on di...Kurt Naugles M.D., M.P.H.
Self-Management in this presentation refers to those activities people undertake in an effort to promote health, prevent disease, limit illness, and restore well being. Several investigators contend that self-management be made a major component of many patient health-care strategy (Glasgow, et al., 2001; Wagner, et al., 2001). Currently, nearly 125 million Americans suffer from chronic debilitating illnesses (Anderson, 2000). These national figures clearly underscore the need to develop a multidimensional approach in regards to disease management. Accordingly, measures that incorporate the patient’s perspective in managing his or her health should be explored.
Diabetes mellitus is among those conditions suspected to be highly influenced by self-management activities (Sprangers, et. al., 2000). If benefits do indeed exist, they need to be fully evidenced. The investigation presented here sought to examine the role self management plays in the health outcomes of individuals living with diabetes.
Resurge - The Godzilla Of Offers - Resurge weight loss.Med Gaith
Resurge- The Godzilla Offers is a blend of natural products that are helpful to losing weight, boosting the immune system, increasing metabolism, and relieving stress. it is effective against problems that in one way or another are related to weight gain. It is made in the USA and approved by the Food and Drug Administration (FDA).
share - Lions, tigers, AI and health misinformation, oh my!.pptxTina Purnat
• Pitfalls and pivots needed to use AI effectively in public health
• Evidence-based strategies to address health misinformation effectively
• Building trust with communities online and offline
• Equipping health professionals to address questions, concerns and health misinformation
• Assessing risk and mitigating harm from adverse health narratives in communities, health workforce and health system
Local Advanced Lung Cancer: Artificial Intelligence, Synergetics, Complex Sys...Oleg Kshivets
Overall life span (LS) was 1671.7±1721.6 days and cumulative 5YS reached 62.4%, 10 years – 50.4%, 20 years – 44.6%. 94 LCP lived more than 5 years without cancer (LS=2958.6±1723.6 days), 22 – more than 10 years (LS=5571±1841.8 days). 67 LCP died because of LC (LS=471.9±344 days). AT significantly improved 5YS (68% vs. 53.7%) (P=0.028 by log-rank test). Cox modeling displayed that 5YS of LCP significantly depended on: N0-N12, T3-4, blood cell circuit, cell ratio factors (ratio between cancer cells-CC and blood cells subpopulations), LC cell dynamics, recalcification time, heparin tolerance, prothrombin index, protein, AT, procedure type (P=0.000-0.031). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and N0-12 (rank=1), thrombocytes/CC (rank=2), segmented neutrophils/CC (3), eosinophils/CC (4), erythrocytes/CC (5), healthy cells/CC (6), lymphocytes/CC (7), stick neutrophils/CC (8), leucocytes/CC (9), monocytes/CC (10). Correct prediction of 5YS was 100% by neural networks computing (error=0.000; area under ROC curve=1.0).
Here is the updated list of Top Best Ayurvedic medicine for Gas and Indigestion and those are Gas-O-Go Syp for Dyspepsia | Lavizyme Syrup for Acidity | Yumzyme Hepatoprotective Capsules etc
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
ABDOMINAL TRAUMA in pediatrics part one.drhasanrajab
Abdominal trauma in pediatrics refers to injuries or damage to the abdominal organs in children. It can occur due to various causes such as falls, motor vehicle accidents, sports-related injuries, and physical abuse. Children are more vulnerable to abdominal trauma due to their unique anatomical and physiological characteristics. Signs and symptoms include abdominal pain, tenderness, distension, vomiting, and signs of shock. Diagnosis involves physical examination, imaging studies, and laboratory tests. Management depends on the severity and may involve conservative treatment or surgical intervention. Prevention is crucial in reducing the incidence of abdominal trauma in children.
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachAyurveda ForAll
Explore the benefits of combining Ayurveda with conventional Parkinson's treatments. Learn how a holistic approach can manage symptoms, enhance well-being, and balance body energies. Discover the steps to safely integrate Ayurvedic practices into your Parkinson’s care plan, including expert guidance on diet, herbal remedies, and lifestyle modifications.
DISSERTATION on NEW DRUG DISCOVERY AND DEVELOPMENT STAGES OF DRUG DISCOVERYNEHA GUPTA
The process of drug discovery and development is a complex and multi-step endeavor aimed at bringing new pharmaceutical drugs to market. It begins with identifying and validating a biological target, such as a protein, gene, or RNA, that is associated with a disease. This step involves understanding the target's role in the disease and confirming that modulating it can have therapeutic effects. The next stage, hit identification, employs high-throughput screening (HTS) and other methods to find compounds that interact with the target. Computational techniques may also be used to identify potential hits from large compound libraries.
Following hit identification, the hits are optimized to improve their efficacy, selectivity, and pharmacokinetic properties, resulting in lead compounds. These leads undergo further refinement to enhance their potency, reduce toxicity, and improve drug-like characteristics, creating drug candidates suitable for preclinical testing. In the preclinical development phase, drug candidates are tested in vitro (in cell cultures) and in vivo (in animal models) to evaluate their safety, efficacy, pharmacokinetics, and pharmacodynamics. Toxicology studies are conducted to assess potential risks.
Before clinical trials can begin, an Investigational New Drug (IND) application must be submitted to regulatory authorities. This application includes data from preclinical studies and plans for clinical trials. Clinical development involves human trials in three phases: Phase I tests the drug's safety and dosage in a small group of healthy volunteers, Phase II assesses the drug's efficacy and side effects in a larger group of patients with the target disease, and Phase III confirms the drug's efficacy and monitors adverse reactions in a large population, often compared to existing treatments.
After successful clinical trials, a New Drug Application (NDA) is submitted to regulatory authorities for approval, including all data from preclinical and clinical studies, as well as proposed labeling and manufacturing information. Regulatory authorities then review the NDA to ensure the drug is safe, effective, and of high quality, potentially requiring additional studies. Finally, after a drug is approved and marketed, it undergoes post-marketing surveillance, which includes continuous monitoring for long-term safety and effectiveness, pharmacovigilance, and reporting of any adverse effects.
- Video recording of this lecture in English language: https://youtu.be/kqbnxVAZs-0
- Video recording of this lecture in Arabic language: https://youtu.be/SINlygW1Mpc
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
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Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
2. RANDOMIZED CLINICAL TRIAL OF WEIGHT LOSS 367
obtained from the Weight Control Information Network, 1 WIN THE NEED FOR AN RCT
WAY, Bethesda, MD 20892-3665.) Is current knowledge of the benefits of losing weight suffi-
ciently compelling to render unnecessary a large and costly RCT
of the health effects of intentional weight loss? On the converse
CURRENT KNOWLEDGE OF INTENTIONAL WEIGHT issue, the harm of gaining weight, workshop participants gener-
LOSS ally agreed that the evidence available, such as that from the
Nurses’ Health Study (13), clearly and consistently shows that
Animal models weight gain during adulthood corresponds to increased risk of
Studies conducted with animal models (eg, Zucker obese rats) cardiovascular disease and that risk of both cardiovascular dis-
have shown that restricting energy intake can dramatically ease and type 2 diabetes increases with increasing weight. On the
increase longevity. No information, however, was presented at other hand, observational studies do not clearly show that inten-
the workshop on the effects of interventions designed to reduce tional weight loss sustained over the long term reduces health
the weight of obese animals on morbidity or mortality. risks. Intentionality has generally not been assessed, and the
extent to which weight loss is sustained in the long term is fre-
Human studies quently unknown. It is also unclear whether successful, inten-
Information on the long-term health effects of weight loss in tional weight loss can reverse established pathology to the degree
humans has come primarily from observational studies, several that disease risk is lowered meaningfully. Finally, variability in
of which raised concerns about the safety of intentional weight obesity-related covariates, such as physical inactivity, can con-
loss or weight variability resulting from unsustained weight fuse attempts to sort out the effects of weight or weight loss on
loss. Data from both the Framingham Heart Study (7) and the health because the covariates themselves can cause ill health.
Multiple Risk Factor Intervention Trial (8) suggest that weight Even when the risks and benefits of an intervention seem obvi-
loss may be associated with adverse health consequences, but ous, conducting an RCT could reveal unforeseen results. About 2
that this may occur primarily in the leanest subjects. In the decades ago, for example, RCTs of 2 scientifically plausible
Framingham study, those who lost weight ultimately had higher treatments [estrogen treatment to prevent cardiovascular disease
mortality rates than those who did not lose weight, even though in men (14) and clofibrate treatment for hypercholesterolemia
persons who initially lost weight experienced more favorable (15)] revealed that both caused unexpected, harmful outcomes.
changes in blood pressure and serum cholesterol (9). Intentional The general use of RCTs to estimate the efficacy of behavioral
weight loss was not examined directly in either study. A interventions has been criticized (16). In the case of intentional
prospective 12-y study that assessed the intentionality of weight weight loss, however, workshop participants believed that exper-
loss, conducted with the American Cancer Society’s Cancer Pre- imental testing is warranted because efforts by obese persons to
vention Study I cohort (10), found that intentional weight loss lose weight are common; economic costs of implementing effec-
among women with obesity-related comorbidities (such as type tive, sustained weight-loss interventions within the clinical care
2 diabetes) is associated with increased longevity; among system are substantial; and concern lingers over the safety of los-
women with no preexisting illness, however, the association was ing weight intentionally.
ambiguous. It was noted in the discussion at the workshop that
even in those few studies in which losing weight appeared to
have a positive effect on health, the relative importance of EFFECT OF AN RCT ON HEALTH CARE POLICY
energy restriction, food substitution, and physical activity was Estimates derived from an RCT of the health and economic
unclear, as was the role of self-selection. All of these factors are effects of intentional weight loss will allow the clinical and pub-
difficult to control in observational studies, and workshop par- lic health communities to better judge the value of investment in
ticipants agreed that current studies do not provide the data nec- obesity treatment. For example, is obesity treatment cost-effec-
essary to address these questions. tive? Such knowledge would help guide resource decisions about
Preliminary data from a long-term research initiative, the clinical and public health programs for obesity treatment, includ-
Swedish Obese Subjects Study, which is controlled but not ran- ing the development of reimbursement guidelines for managed
domized, show that obesity-related comorbid conditions were care organizations and for third-party payers.
markedly reduced in a cohort of obese men [body mass index
(BMI; in kg/m2) > 38] and women (BMI > 34) who underwent gas-
tric surgery to lose weight. Morbidity and mortality are being ISSUES RELATED TO THE INTERPRETATION OF AN
studied over a 10-y follow-up period; obesity-associated costs and RCT
quality of life are being assessed as well (11). Two-year follow-up Can an RCT separate the effects on health outcomes of weight
data from this study indicated that among those who lost weight, loss per se from the effects of the weight-loss interventions?
all cardiovascular disease risk factors, with the exception of cho- What is the efficacy of currently available weight-loss interven-
lesterol concentrations, improved significantly, whereas most risk tions? Is it appropriate to have a control group, and how might
factors worsened among those who gained weight (12). Self-selec- this group be “treated?” These issues were discussed at some
tion of participants to the intervention and control groups and length.
restriction of the population to the severely obese are major limi-
tations of the Swedish study. Workshop participants concluded Treatment effects compared with weight-loss effects
that more information is needed on the long-term health effects of Subjects in an RCT could not be randomly assigned to lose or
intentional weight loss in persons with lesser degrees of obesity, not lose weight; they could only be randomly assigned to receive
who constitute the majority of obese individuals for whom weight or not receive interventions that might result in weight loss.
loss is currently recommended. These interventions, however, might well produce changes in
3. 368 YANOVSKI ET AL
health status that are not due to weight loss. Promotion and this light, having a control group might not be seen as creating
maintenance of weight loss through increased physical activity, an ethical problem of withholding beneficial treatment. Further-
reduced saturated fat intake, and consumption of large amounts more, questions raised regarding the putative harmful associa-
of fruit and vegetables are examples of such interventions. It tions between weight loss and long-term health argue that not
may appear that one could never infer that weight loss itself providing weight-loss treatment to obese persons in a clinical
caused the changes in health status. However, if participants in trial may be appropriate.
an RCT were randomly assigned to several interventions that
produce weight loss through different mechanisms and these
interventions yielded similar improvements in health status, then DESIGNING AN RCT
the conclusion that weight loss was responsible for the improve-
ments in health outcomes may be justified. Study population
The 2 key issues in identifying study populations are the sta-
Efficacy of current weight-loss treatments tistical power of the study and the generalizability of the find-
In experimental studies of weight loss, well-executed studies ings. Age, sex, race-ethnicity, degree of obesity, and presence of
using currently available pharmacologic or behavioral interven- comorbid conditions should be considered in choosing the study
tions rarely result in more than 8–10% average reductions in body population. Because the RCT should address the public health
weight (17). The lowest weight is generally reached 6 mo after effect of weight loss, the study population should reflect the dis-
the intervention begins and is rarely maintained by the average tribution of obesity in the United States. Including men and
participant for longer than another 12 mo, at which time the par- women of various socioethnic backgrounds is important because
ticipant’s body weight begins to increase back toward its prein- of the adverse secular trends toward increased weight among
tervention level (18). Even such relatively brief reductions in racial and ethnic minority populations (21). In addition, the rela-
weight have produced clinically meaningful changes in interme- tion between obesity and health may differ by sex or ethnicity.
diate physiologic risk factors (such as blood pressure or choles- Older adults should be included because both the risks and ben-
terol) for morbidity and mortality in the short-to-medium term. efits of weight loss are less clear in this population. Younger
On the other hand, although a large proportion of the US popula- adults should be included as well; a study by Stevens et al (22)
tion reports intentionally losing weight (19), the value, and even suggested that the risk of obesity-related mortality is higher in
the safety, of intentional weight loss on long-term health is being younger subjects.
seriously questioned (3). Thus, a valid and useful function of the The issue of the degree of obesity of study subjects sparked
RCT would be to specifically evaluate the efficacy (in terms of considerable controversy. Some workshop participants sug-
both risk and benefits) of current weight-loss practices. gested including persons who are mildly obese because these
persons are more prevalent in the population than the severely
Control group obese and because there is less certainty about the health bene-
Theoretically, the control group should include obese persons fits of weight loss in this group. Others asserted that persons
who do not intentionally lose weight during the entire study, and with more severe obesity should be the focus of study, particu-
the health status and health outcomes of these participants larly those with obesity-related comorbid conditions, to ensure
should be monitored in the same way as the health status and an adequate rate of development of clinical events, such as car-
health outcomes of participants randomly assigned to the inter- diovascular endpoints. In absolute terms, most obesity-associ-
vention groups. Good RCT practice also dictates that partici- ated disease risk occurs among moderately overweight persons
pants and investigators in all treatment groups, including the because of their number in the general population. Furthermore,
control group, be blinded to treatment status. Because obese per- the distribution of abnormalities that influence risk in moder-
sons in our society are likely to try to lose weight, especially ately overweight persons does not differ substantially from the
through self-treatment, it is possible that any control group distribution in higher weight groups, suggesting that an adequate
would try to lose weight in parallel with the treatment groups, number of clinical events could be obtained in this population.
which might bias results of the trial toward showing no differ- On the other hand, very large persons (ie, those with a BMI > 40)
ence. In addition, neither participants nor study providers in any should not be excluded from any study because few data are
of the control or intervention groups could be blinded to their available for this population.
status. On the other hand, it may be feasible to maintain control
groups who do not lose weight in long-term studies by providing Interventions
them with a minimal intervention of a self-help manual on Interventions in an RCT can be behavioral, pharmacologic, or
weight loss and healthy eating (20). Obese control groups often both.
have greater retention rates than do treatment groups. This result
Behavioral interventions
is believed to be attributable to the control group members feel-
ing less embarrassed than their intervention group counterparts if Effective behavioral interventions generally include a
they do not lose weight or if they regain lost weight. hypoenergetic diet, moderate-intensity physical activity, and
In the workshop discussion, the issue was also raised of behavioral techniques such as self-monitoring, stimulus control
whether it is ethical to have a control group in which participants (for example, restricting the places in which food is consumed),
do not receive weight-loss treatment, even though we do not cur- and relapse prevention. Treatment is often provided in groups,
rently know how beneficial weight loss is in terms of changes in with meetings initially held weekly and then less often. Results
long-term health status. It was pointed out that even a minimal from recent treatment studies show that weight loss averages
control intervention provided by a study is more than many 8–10% over 26 wk, with some regain typical after treatment.
obese persons ever receive from their own physicians. Viewed in Average weight loss 1 y after treatment is 6% of initial body
4. RANDOMIZED CLINICAL TRIAL OF WEIGHT LOSS 369
weight (23). There is some indication that modest weight loss ameliorated by comparing any drug treatments with behavioral
can be sustained over the long term. The Trial of Nonpharma- treatment alone (with or without placebo), so that any added
cologic Interventions in the Elderly (24) recently reported a benefit or deleterious effect of the drug treatment could be
mean weight loss of > 4.5 kg at 30 mo in overweight, older determined.
adults who received instruction in diet, physical activity, and
behavioral skills, compared with a mean weight loss of < 1 kg in Relevant health outcomes
those not assigned to weight-loss intervention. Data from other Choosing outcome measurements for an RCT is extremely
behavioral studies show even more impressive results with long- important because these measurements affect nearly all deci-
term, intensive behavioral therapy, with weight loss equal to or sions made about the other key attributes of the trial, including
exceeding that in trials of pharmacologic agents (25, 26). Treat- the target population, the length of the study, and the sample
ments including moderate energy restriction (4180–6280 kJ/d), size. Trial outcomes must be clinically relevant and compelling
behavioral techniques, and ongoing support can be effective in and they must be biologically responsive to the treatments being
producing substantial weight loss at 1 y; the best results are studied. They also must be measured reliably, accurately, and
achieved with more intensive programs. When patient contact identically across the treatment and control groups. RCT health
decreases or is stopped, weight is regained. outcomes can be classified as functional outcomes (eg, serum
glucose concentrations), severity-stage outcomes (eg, progres-
Pharmacologic treatment sion of cardiovascular disease or onset of diabetes), and ultimate
(Note that this workshop was held before the release of infor- outcomes (eg, total or cardiovascular mortality). Because the
mation on the association between valvular heart disease and RCT literature on the effect of weight loss on functional out-
fenfluramine-dexfenfluramine and the subsequent withdrawal of comes is well established, the primary outcome measurements
these medications from the market.) for an RCT of weight loss and long-term health should include
Numerous studies have found that pharmacologic treatment severity-stage and ultimate outcomes.
confers a modest but significant increase in weight loss com-
Mortality
pared with that obtainable by behavioral treatment alone (17).
Weight generally decreases for the first 6 mo of pharmacologic Total mortality is perhaps the most useful health outcome, espe-
treatment and this loss is generally maintained while drug ther- cially if a target population is chosen of obese young and middle-
apy continues over the ensuing 6 mo. Some patients, however, do aged adults, both because observational data suggest that the rela-
regain weight despite continuing treatment (17). In general, obe- tive risk of obesity for mortality is most elevated in this group (22)
sity-related risk factors such as blood pressure and hyperlipi- and because this population potentially has many years of life
demia decrease commensurately with weight loss; however, this remaining. The demographic realities, however, mean that an RCT
reduction may be medication specific (17). Both controlled (27) of weight loss and mortality carried out in this population would
and uncontrolled (28) studies have suggested that weight loss likely require an extremely long follow-up to find meaningful dif-
can be sustained over longer terms (ie, > 2 y), but few studies ferences in mortality across treatment groups. Such a trial might be
have evaluated the safety or efficacy of weight-loss medications prohibitively expensive, and using cause-specific mortality as the
for > 12 mo (17). primary outcome would be even less feasible. A better approach
As additional weight-loss medications become available for might be to study those who have established comorbidities, such
long-term use, assessing their risks and benefits as an adjunct to as type 2 diabetes, because their risk of death is elevated. There was
behavioral weight-loss treatment becomes critical. Because an consensus among the workshop participants that total and cause-
RCT evaluating the health effect of sustained, intentional weight specific mortality may not be feasible primary health outcomes in
loss requires the ability to assist subjects in maintaining weight an RCT, but there was concern about not monitoring mortality. If
loss over the long term and because the primary benefit of phar- mortality differences are not compared across treatment groups,
macotherapy appears to be in enhancing weight maintenance, adverse associations of weight loss and mortality, which have been
one or more medication interventions should be included in the found in some observational studies, would be missed.
RCT if safe and effective drugs are available. Medication should
Morbidity
be combined with behavioral treatment because studies suggest
that these treatments interact beneficially (17). It is anticipated After mortality, morbidity (or disease incidence) was consid-
that, as with behavioral treatment, medication effects will not be ered to be the most relevant health outcome. Cardiovascular dis-
sustained when the drug is discontinued; therefore, any drug ease incidence (eg, development of myocardial infarction,
treatment should be continued throughout the trial. stroke, or angina) would be a primary candidate because of the
Several workshop participants contended that the RCT well-established relations between obesity, weight loss, and
should address the question of whether weight loss improves physiologic risk factors for cardiovascular disease. Furthermore,
people’s lives in the longer term and not focus more narrowly on cardiovascular disease is common in the US adult population and
the efficacy of a particular drug. It was noted that no drug cur- imposes high social and economic costs.
rently used for weight loss has safety or efficacy data available In addition to cardiovascular disease, obesity is strongly asso-
for ≥ 5 y, the time some participants thought would be necessary ciated with the incidence of other important health outcomes,
for determining relevant clinical events. Combining medications including type 2 diabetes, sleep apnea, osteoarthritis, gall blad-
(as in a stepped-care approach for hypertension) was suggested der disease, and some cancers. Consideration should be given to
as being of possible value. Concern was also expressed that neg- monitoring these other morbid outcomes. In practice, because of
ative outcomes from a drug-only treatment could lead to the statistical power considerations, these outcomes would likely
mistaken conclusion that weight loss is bad rather than that the need to be combined into a summary outcome. Consideration
medication caused the negative result. This concern could be should also be given to combining morbidity and mortality end-
5. 370 YANOVSKI ET AL
points within a specific disease category, such as cardiovascular rate of reaching the primary outcome during the follow-up
disease, for which this is a well-established tradition (29–31). period ( c). For the proposed clinical trial, we assume that the
control group’s time (t) to the primary outcome is exponentially
Quality of life
distributed (ie, cumulative incidence = 1 e t). The sample
For many patients, overall quality of life is significantly size scenarios consider 3 primary outcome hazard rates for the
affected by obesity. Improvements in quality of life have been control group: 2.5%/y (eg, fatal or nonfatal myocardial infarc-
reported in association with weight loss (32) and these may vary tion), 5.0%/y, and 7.5%/y (eg, clinical progression to diabetes).
significantly with the type of weight-loss treatment and the sub- In determining sample size, a clinically important difference
sequent maintenance regimen used. In addition, if one conducts must be specified between the control group and the intervention
a formal assessment of the differences in cost-effectiveness of group. This difference may be specified in terms of the relative
treatments, adjustments for various quality-of-life components hazard rate, i/ c, where i is the primary outcome hazard rate in
related to both the health outcomes and the treatments are the intervention group. We consider 3 values of i/ c: 0.75 (25%
required (33). Although assessment of quality of life would be reduction in c experienced by the intervention group), 0.67
essential to conducting a modern, high-quality RCT, it was gen- (33% reduction), and 0.60 (40% reduction).
erally agreed that this variable should not be a primary health In selecting a sample size, one should try to maximize statis-
outcome. tical power and minimize type I error. In the present scenario, the
type I error rate is the probability of rejecting the hypothesis that
Adverse events
the control group and the intervention group are equivalent when
Adverse events will need to be monitored, especially if the the true cumulative incidence of the primary outcome over time
RCT includes one or more drug treatments. If investigational is the same for the 2 groups (ie, the intervention is not effective).
drugs are used, formal adverse event reporting will be mandated Statistical power is the probability of rejecting the hypothesis
by federal regulatory requirements and good clinical practice that the control and intervention groups are equivalent when the
guidelines. In addition to the safety and ethical considerations true cumulative incidence of the primary outcome over time dif-
that dictate monitoring adverse events, the treatment costs of fers for the 2 groups. For the present illustration, we set the type
adverse events and associated changes in quality of life need to I error rate at 5% (two-sided) and the statistical power at 90%.
be accurately assessed in any cost-effectiveness analysis com- Loss to follow-up is defined as the cessation by a randomly
paring the efficacy of treatments. assigned participant of scheduled follow-up visits before the sched-
uled end of the study. The number of randomly assigned partici-
Statistical considerations pants must be large enough to achieve the statistical power even
Determination of sample size should take into account 1) the with losses to follow-up. We assumed that losses to follow-up are
number and configuration of the control group and the interven- exponentially distributed and set the loss hazard rate at 5%/y.
tion group or groups, 2) the duration of participant follow-up, 3) To calculate sample sizes we used the formula of Lachin and
the control group’s rate of developing the primary outcome, 4) Foulkes (equation 6.2 in reference 34). Alternative sample size goals
the minimum detectable difference between the intervention per group (intervention or control) as a function of c and the per-
group or groups and the control group, 5) statistical power, and centage reduction in c experienced by the intervention group are
6) the rate of losses to follow-up. Workshop participants pro- presented in Table 1 for a maximum study duration of 5 y (average:
posed several research designs, with various numbers and con- 4 y). For example, the total sample size required to ensure 90%
figurations of intervention groups. Rather than review each of power of detecting a ≥ 33% reduction in the intervention group of a
these at length, we discuss as an example how sample size is c = 0.050/y (ie, a i of 0.033/y) is 967 per group, based on a level
determined in a 2-group design given certain assumptions. of significance of 5% (two-sided) and a loss hazard rate of 5%/y.
Assume that the RCT will test the effectiveness of a single For a maximum duration of 10 y (average: 9 y) and the same
intervention on the cumulative incidence of the primary outcome assumptions, a different set of sample sizes would be calculated
with use of a control group for comparison. Half of the eligible (Table 2). For example, the total sample size required to ensure 90%
participants are randomly assigned to the intervention group power of detecting a ≥ 33% reduction in the intervention group of a
(pharmacologic or nonpharmacologic treatment or both) and half c = 0.050/y (ie, i of 0.033/y) is 528 per group.
are randomly assigned to the control group. Participants are ran- Note that the sample size per group increases as c decreases,
domly assigned during a fixed time and followed up for the as the percentage reduction in c experienced by the intervention
remainder of that randomization period and an additional fixed group decreases, and as the duration of follow-up decreases.
time after the last participant is assigned. We consider scenarios Adding a second intervention group would increase the sample
with maximum durations of 5 and 10 y. In the first scenario, par- TABLE 1
ticipants are randomly assigned during a 2-y period and are fol- Required sample per group for a maximum study duration of 5 y1
lowed up for an additional 3 y after recruitment closes (follow-
Control group Percentage reduction3
up time in years: minimum, 3; maximum, 5; average, 4). In the
second scenario, participants are randomly assigned during a 2- hazard rate (%/y)2 25 33 40
y period and are followed up for an additional 8 y after recruit- %
ment closes (follow-up time in years: minimum, 8; maximum, 2.5 3395 1857 1209
10; average, 9). 5.0 1771 967 629
The principal outcome in this example is the time to a speci- 7.5 1231 671 436
fied primary outcome (eg, death, cardiovascular morbidity, non- 1
Average follow-up of 4 y (range: 3–5 y).
cardiovascular morbidity, or some combination of these). A key 2
Primary outcome rate.
feature in sample size determination will be the control group’s 3
Reduction among the intervention group in the control group hazard rate.
6. RANDOMIZED CLINICAL TRIAL OF WEIGHT LOSS 371
TABLE 2 achieve the weight-loss goals. The option of conducting several
Required sample per group for a maximum study duration of 10 y1 small studies rather than a single large clinical trial was also intro-
Percentage reduction3 duced. Adding a weight-reduction component with pharmacologic
Control group
hazard rate (%/y)2 25 33 40
treatment to the ongoing Diabetes Prevention Program (36) was
also proposed as a potentially cost-effective option.
% Continued interactions among the staffs of the National Insti-
2.5 1779 971 632 tutes of Health and the Centers for Disease Control and Preven-
5.0 971 528 343 tion, the National Task Force on Prevention and Treatment of
7.5 704 382 247 Obesity, the National Institute of Diabetes and Digestive and
1
Average follow-up of 9 y (range: 8–10 y). Kidney Diseases Scientific Advisory Council, and other experts
2
Primary outcome rate. will determine the optimal research design characteristics for
3
Reduction among the intervention group in the control group hazard rate. obtaining valid scientific data on the long-term health effects of
intentional weight loss. Such information will ultimately provide
per group to allow for multiple comparisons of the 3 groups (35). millions of obese Americans with guidance on the risks and ben-
Other considerations in calculating required sample size include efits of weight loss.
noncompliance with the assigned intervention, nonuniform
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