Skip Navigation
Department of Health and Human Services www.hhs.gov
 
 

Return to Webcast Page

What Works to Prevent Obesity in Children? A Comparative Effectiveness Review and Meta-Analysis

Slide Presentation in Text Format


Slide 1

What Works to Prevent Obesity in Children?
Findings from a Comparative Effectiveness Review and Meta-Analysis

September 26, 2013
Bruce Seeman, Agency for Healthcare Research and Quality (AHRQ)
Youfa Wang, M.D., M.S., Ph.D., Johns Hopkins University Bloomberg School of Public Health & School of Medicine

Slide 2
Agenda

  • AHRQ and the Effective Health Care Program
  • What Works to Prevent Obesity in Children? A review of findings from Dr. Wang
  • Questions and Answers

Slide 3
Web Conference Logistics

  • Audio lines have been muted to minimize background noise.
  • To ask a question:
    • Use the WebEx Q&A function: You may ask a question for the presenter at any time. Questions will be answered midway through and at the very end of the presentation.
    • If you are experiencing technical issues, you may also use the WebEx Q&A function to request help.
  • Let us know what you think! Completed the evaluation form at the conclusion of the presentation. Look for the “Evaluation” pop-up.

Slide 4
Agency for Healthcare Research and Quality (AHRQ)

  • Mission: To improve the quality, safety, efficiency, and effectiveness of health care for all Americans
  • Research: ~80 percent of AHRQ's budget is invested in grants and contracts focused on improving health care
  • The AHRQ Effective Health Care (EHC) Program:
    • Provides current, unbiased evidence on clinical effectiveness of health care interventions
    • Focuses on patient-centered outcomes
    • Helps consumers, providers, and policy-makers make informed choices
    • Does not make treatment recommendations
    • Long-term goal: Improve health care quality and patient health outcomes through informed decision making by patients, providers, and policymakers

Slide 5
What is Comparative Effectiveness Research (CER)?

  • Comparative effectiveness research — a type of patient-centered outcomes research — compares drugs, medical devices, tests, surgeries, or ways to deliver health care, so that patients and their families can make more informed choices.
  • Findings are descriptive, not prescriptive, and are intended as tools for informed decision making, not recommendations.
  • Findings highlight current evidence about effectiveness, risks, and side effects.

Slide 6
What Works to Prevent Obesity In Children? Findings from a Comparative Effectiveness Review and Meta-Analysis

Slide 7
Disclaimer

  • Some of what will be presented is not included in the original 800-page AHRQ report.
  • Some is based on further analysis, unpublished results.

Slide 8
Outline

  • Introduction
  • Objectives
  • Methods
  • Results
  • Conclusions

Wang Y, Wu Y, Wilson RF, et al. AHRQ Comparative Effectiveness Review No. 115.
Available at www.effectivehealthcare.ahrq.gov/child-obesity-prevention.cfm.

Slide 9
Conclusions/Take Home Message

  • Obesity is a serious public health problem
  • The evidence is moderate about the effectiveness of school-based interventions for childhood obesity prevention
  • Physical activity interventions in a school-based setting with a family component or diet and physical activity interventions in a school-based setting with home and community components have the most evidence for effectiveness
  • More research is needed to test interventions in other settings, such as policy, environmental, and consumer health informatics strategies

Slide 10
I. Background: Prevalence of Childhood Obesity

  • Childhood overweight and obesity are highly prevalent in the United States and many other countries
  • The risk of obesity is higher among minority and underserved populations in the U.S.

Slide 11
Worldwide Prevalence of Combined Prevalence of Overweight and Obesity in Children and Adolescents*

Image: A map depicting prevalence of overweight and obesity in children and adolescents worldwide.

* The prevalence estimates were calculated as the arithmetic mean of the age-specific estimates (Data Source: Pigeot et al. 2011)

Slide 12
Trends in the prevalence (%) of obesity (BMI≥95th percentile) in US children and adolescents, by age: 1971-74 to 2009-10*

Chart: Line chart depicting trends in the prevalence by percentage of obesity in U.S. children and adolescents, by age over the years 1971-74 to 2009-10.

*Based on national data collected in NHANES. (Wang and Beydoun, 2007; Ogden et al, 2012)

Slide 13
What prevalence may not show—U.S. adolescents: Yearly average change in BMI (kg/m2), WC (cm) and TST (mm) by their percentile distributions: 1988-94 to 1999-04

Chart 1: Chart depicting yearly change among boys ages 12-19 years of age and cumulative proportion of body mass index, waist circumference, and triceps skinfold thickness.

Chart 2: Chart depicting yearly change among girls ages 12-19 years of age and cumulative proportion of body mass index, waist circumference, and triceps skinfold thickness.

Slide 14
The Biological Basis of Obesity

Image: A diagram of environmental and societal influences on energy regulation and body fat stores.

Slide 15
Factors Contributing to Childhood Obesity

  • Many factors interact to contribute to obesogenic environments, and affect children’s weight, e.g.,
    • Genetic and other individual factors
    • Home influences
    • School environment
    • Local community
    • Regional, national policy
    • Globalization
    • More …

Slide 16
IOTF Causal Web of Societal Processes Influencing the Population Prevalence of Obesity

Chart: Flow chart of international; national/regional; community/local; work/home/school; individual; and population influences on obesity prevalence.

Source: International Obesity Task Force [www.iotf.org] (Kumanyika et al IJO 2002;26:425-36)

Slide 17
Physical Activity and Eating Behaviors Are Affected By Many Factors

Image: Diagram of public policy, community, organizational, interpersonal, and individual factors that affect physical activity and eating behaviors.

Slide 18
Childhood Obesity Prevention

  • Obesity is difficult to treat, and prevention of childhood obesity is key
  • It’s been of debate who should play a more important role, e.g., individual/parents vs. society/government
  • Leading health organizations have recommended comprehensive interventions to fight obesity, and argue that government should play an important role

Slide 19
How to Prevent Childhood Obesity?

Figure: This figure illustrates the continuum from prevention to treatment approaches.

Source: Daniels SR, et al. Overweight in children and adolescents: pathophysiology, consequences, prevention, and treatment. Circulation. 2005;11:1999-2012.

Slide 20
U.S. National Initiatives

  • Let’s Move!
  • Childhood Obesity Task Force
  • HHS Healthy Weight Task Force
  • National Action Plan for Physical Activity
  • Healthy People 2020
  • Dietary Guidelines for Americans 2010
  • Communities Putting Prevention to Work (CPPW)
  • Child Nutrition Reauthorization – Healthy Hunger-free Kids Act
  • Surgeon General’s Call to Action on Breastfeeding
  • FTC Guidelines for Foods Marketed to Children

Image: Photos of First Lady Michelle Obama promoting the Let’s Move! Program.

Slide 21
II. Objectives of Our Review/Study

  • Assess the effectiveness of childhood obesity prevention programs conducted in high-income countries
  • All kinds, in any of the following settings:
    • School
    • Home
    • Primary care clinic
    • Childcare center
    • Community setting
    • Consumer health informatics
    • A combination of the above

Slide 22
Key Questions (KQ) Addressed

  • KQ1. What is the comparative effectiveness of school-based interventions for the prevention of obesity or overweight in children?
  • KQ2. What is the comparative effectiveness of home-based interventions for the prevention of obesity or overweight in children?
  • KQ3. What is the comparative effectiveness of primary care-based interventions for the prevention of obesity or overweight in children?
  • KQ4. What is the comparative effectiveness of childcare setting-based interventions for the prevention of obesity or overweight in children?
  • KQ5. What is the comparative effectiveness of community-based or environment-level interventions for the prevention of obesity or overweight in children?
  • KQ6. What is the comparative effectiveness of consumer health informatics applications for the prevention of obesity or overweight in children?
  • KQ7. What is the comparative effectiveness of multi-setting interventions for the prevention of obesity or overweight in children?

Slide 23
III. Methods

  • The study was conducted following the standard process of the AHRQ EHC Program
  • A wide range of experts and stakeholders from academic institutions, government agencies, and parent stakeholders provided feedback throughout the study process

Slide 24
Study Process

  • Topic (study protocol) refinement
  • Literature search & data abstraction
  • Data analysis
  • AHRQ research report development
  • Public review/comment
  • Revisions of report
  • Publication(s)—report and papers

Slide 25
Figure 1. Analytic framework: Evaluation of Childhood Obesity Intervention Programs

Figure: Flow chart depicting evaluation of childhood obesity intervention programs in children age 2018 years in key settings.

Slide 26
Literature Search

  • Data sources. We searched MEDLINE®, Embase®, PsycInfo®, CINAHL®, clinicaltrials.gov, and the Cochrane Library through August 11, 2012.
  • Randomized controlled trials, quasi-experimental studies, or natural experiments conducted in high-income countries enrolling healthy children aged 2-18 and following participants for at least one year (or six months for school-based studies) were included.

Slide 27
Data Abstraction

  • Two reviewers independently reviewed each article for eligibility. For each study, one reviewer extracted the data and a second reviewer verified the accuracy.
  • Both reviewers assessed the risk of bias for each study.
  • Together, the reviewers graded the strength of the evidence (SOE) supporting interventions—diet, physical activity, or both—in each setting for the outcomes of interest.

Slide 28
Analysis—Qualitative Analysis Rate The Strength Of Evidence (SOE)

  • SOE was classified into four broad categories:
    • High: Further research is very unlikely to change the confidence in the estimate of effect.
    • Moderate: Further research may change the confidence in the estimate of effect and may change the estimate.
    • Low: Further research is likely to change the confidence in the estimate of effect and is likely to change the estimate.
    • Insufficient: Evidence either is unavailable or does not permit a conclusion.

Slide 29
Meta-analysis—‘Quantitative Analysis’

  • When >=3 comparable studies were available for a given intervention and setting(s), we conducted meta-analyses
    • Using STATA (version 11·0; Stata Corp.)
  • We used random effect models with the method of DerSimonian and Laird due to heterogeneity among studies
  • Outcomes:
    • BMI—report
    • BP
    • blood lipids

Slide 30
Questions & Answers

Slide 31
Results

  • We identified 34,545 unique citations and included 131 articles describing 124 interventional studies.
  • The majority of the interventions (104 studies) were school-based, although many of them included components delivered in other settings.
  • Most were conducted in the United States and in the past decade.

Slide 32

Figure: Flow chart literature search results.

Total: 131 (124 studies)

KQ1 - School-based – 110 (104 stud)
KQ2 - Home-based – 6 (6 studies)

KQ3 - Primary care-based – 1 (1 stud)
KQ4 - Child care-based – 5 (4 stud)
KQ5 - Community- Env – 9 (9 stud)

KQ6 - Consumer health informatics
KQ7 - Multi-setting interventions

Slide 33
Figure 3. Meta-analysis: Change in BMI between the control and combined diet and physical activity intervention groups in school-only settings

Figure: Change in BMI between the control and combined diet and physical activity intervention groups in school-only settings.

Slide 34
Figure 4. Meta-analysis: Change in BMI between the control group and combined diet and physical activity interventions in a school setting with a home component

Figure: Change in BMI between the control group and combined diet and physical activity interventions in a school setting with a home component

Slide 35
Evidence for the Benefits of School-Based Interventions (1 of 3)

  • School-Based Interventions Only
    • School-based diet or physical activity interventions prevent obesity or overweight in children.
      • Strength of Evidence: Moderate
    • School-based combination diet and physical activity interventions prevent obesity or overweight in children.
      • Strength of Evidence: Insufficient
  • School-Based Interventions With a Home Component
    • Physical activity interventions within school-based settings with a home component prevent obesity or overweight in children.
      • Strength of Evidence: High
    • Combined diet and physical activity interventions in a school-based setting with a home component prevent obesity or overweight in children.
      • Strength of Evidence: Moderate

Slide 36
School-Based Interventions (2 of 3)

  • School-Based Interventions With a Community Component
    • Combined diet and physical activity interventions in a school-based community setting prevent obesity or overweight in children.
      • Strength of Evidence: Moderate
  • School-Based Interventions With a Home and Community Component
    • Combined diet and physical activity interventions in a school-, home-based community setting prevent obesity or overweight in children.
      • Strength of Evidence: High

Slide 37
School-Based Interventions (3 of 3)

  • School-Based Interventions With a Consumer Health Informatics Component
    • Evidence is insufficient to determine if physical activity or combined diet and physical activity interventions in a school setting with a consumer health informatics component prevent childhood obesity or overweight.
      • Strength of Evidence: Insufficient

Slide 38
Home-Based or Childcare-Based Interventions

  • Home-Based Interventions Only
    • Home-based combination (diet and physical activity) interventions prevent obesity or overweight in children.
      • Strength of Evidence: Low
  • Childcare Center-Based Interventions Only
    • Combined diet and physical activity interventions in a childcare center setting showed no beneficial effect on childhood obesity or overweight prevention.
      • Strength of Evidence: Low

Slide 39
Community-Based or Primary Care–Based Interventions

  • Community-Based Interventions With a School Component
    • Combined diet and physical activity interventions in a community setting with some school involvement prevent childhood obesity or overweight.
      • Strength of Evidence: Moderate
  • Primary Care-Based Interventions Only
    • Evidence is insufficient to determine if combined diet and physical activity interventions in a primary care setting prevent obesity or overweight in children.
      • Strength of Evidence: Insufficient
    • This does not mean that interventions do not work in the primary care setting, but more research is needed.

Slide 40
Additional Results—Unpublished

  • Effects of the intervention on blood pressure
  • Effects of the intervention on blood lipids

Slide 41
Conclusions

  • A large number of intervention studies have been conducted, but the majority are school-based, and are in the U.S.
  • School-based programs involving dietary or physical activity interventions are effective in preventing childhood obesity.
  • Combining a home or community component with a school-based program also works.
  • Evidence is limited regarding the effectiveness of interventions in other settings, more research is needed.

Slide 42
Gaps in Knowledge (1 of 2)

  • A lack of research on the effectiveness of the following types of obesity interventions:
    • Environment-based and policy-based interventions
    • Interventions tested in the primary care or childcare settings
    • Consumer health informatics interventions

Slide 43
Gaps in Knowledge (2 of 2)

  • Lack of good understanding of the contexts and challenges associated with implementing prevention programs in different settings
  • A paucity of information on the effects of various interventions in preventing childhood obesity in populations stratified by gender, age, ethnicity, demographic, or socioeconomic status
  • System-science guided interventions
  • Cost effective analysis

Slide 44
What to Discuss with Your Patients and Their Caregivers (1 of 2)

  • The patient’s BMI and how to diagnose overweight/obesity in children
  • Health consequences of overweight/obesity in children
  • The possible factors contributing to obesity in children
    • e.g., Lack of physical activity, sedentary/screen time, unhealthy diet, inappropriate use of food rewards, eating when not hungry, portion size
  • The importance of monitoring total daily caloric intake as opposed to total daily food intake
  • Important things that can be done at home
  • That clinicians are concerned about childhood obesity and care patients

Slide 45
What to Discuss with Your Patients and Their Caregivers (2 of 2)

  • Effectiveness of the various prevention programs
  • The programs and resources that help children maintain a healthy weight that are available at school or in the community
  • What can be done if healthy food or safe locations for physical activity are not easily accessible to patients and their families
  • Take actions today (e.g., A B C D…)
    • CLOCC's: 5-4-3-2-1 Go!

Slide 46
Acknowledgements – Key collaborators in the AHRQ project

  • JHU: Youfa Wang (PI), Yang Wu (Coordinator), Jodi Segal (Task Leader), Li Cai, Renee F. Wilson (Project Manager), Christine Weston, Oluwakemi Fawole, Sara Bleich, Lawrence J. Cheskin, Nakiya N. Showell, Brandyn Lau, Dorothy T. Chiu, Allen Zhang
  • AHRQ: Christine Chang

Slide 47
Key Informants participated in developing the AHRQ report

Benjamin Caballero, M.D., Ph.D.
Johns Hopkins University

Jean-Pierre Chanione, M.D., Ph.D.
Department of Pediatrics
University of British Columbia
Vancouver, BC, Canada

Cheryl DePinto, M.D., M.P.H.
Department of Health and Mental Hygiene, Baltimore, MD

William Dietz, M.D., Ph.D.
Director of the Division of Nutrition, Physical Activity, and Obesity, CDC

Allison Field, Sc.D.
Department of Pediatrics
Harvard University

Stacey Passaro, M.Eng.
Passaro Engineering
Baltimore, MD

Joanne Spahn, M.S., R.D.
Nutrition Evidence Analysis Library
U.S. Department of Agriculture

Slide 48
Technical Expert Panel

Benjamin Caballero, M.D., Ph.D.
Johns Hopkins University

William Dietz, M.D., Ph.D.
Centers for Disease Control and Prevention (CDC)

Shiriki Kumanyika, Ph.D., M.P.H.
University of Pennsylvania

Anne Scheimann, M.D., M.B.A.
Johns Hopkins University

Joanne Spahn, M.S., R.D.
U.S. Department of Agriculture

Susan Yanovski, M.D.
National Institute of Diabetes and Digestive and Kidney Disorders (NIDDK)

Slide 49
Resources

  • Original Report: Wang et al., Childhood Obesity Prevention Programs: Comparative Effectiveness Review and Meta-Analysis
  • New!
    • Clinician and Consumer Summaries
    • CME/CE activity, and
    • Slide talk
  • All can be found on AHRQ Effective Health Care Program’s Website: http://www.effectivehealthcare.ahrq.gov

Image 1: Childhood Obesity Report

Image 2: Childhood Obesity Clinician Summary

Image 3: Childhood Obesity Consumer Summary

Slide 50
AHRQ’s Health Care Innovations Exchange

  • The Health Care Innovations Exchange contains more than 800 searchable innovations and 1500 quality tools. Visit us at www.innovations.ahrq.gov.
  • Access innovations, tools and resources related to Childhood Obesity at http://innovations.ahrq.gov/innovations_qualitytools.aspx?search=childhood%20obesity.

Slide 50
Questions and Comments?