Obesity: Trends, Impact, Complexity

Transcription

1 Obesity: Trends, Impact, Complexity Ross A. Hammond, Ph.D. Director, Center on Social Dynamics & Policy Senior Fellow, Economic Studies Program The Brookings Institution Attorneys General Education Program April 28 th, 2011

2 Trends and Prevalence

3 Rapid growth since 1970 Since 1970, the percentage of obese Americans has more than doubled, with 1 in 3 adults now obese and 2 in 3 overweight

4 % Incidence of Overweight & Obesity in United States, TOTAL Overweight TOTAL Obesity 10 0 Year

5 Change in BMI Distribution

6 Rapid growth since 1970 Since 1970, the percentage of obese Americans has more than doubled, with 1 in 3 adults now obese and 2 in 3 overweight This is a nation-wide trend in the US: In 1989, no state had obesity prevalence higher than 15%. In 2009, the only state with obesity prevalence lower than 20% was Colorado (18.6%)

7 Obesity Trends* Among U.S. Adults BRFSS, 1990, 1999, 2009 (*BMI 30, or about 30 lbs. overweight for 5 4 person) No Data <10% 10% 14% 15% 19% 20% 24% 25% 29% 30% Source: Behavioral Risk Factor Surveillance System, CDC.

8 Rapid growth since 1970 Since 1970, the percentage of obese Americans has more than doubled, with 1 in 3 adults now obese and 2 in 3 overweight This is a nation-wide trend in the US: In 1989, no state had obesity prevalence higher than 15%. In 2009, the only state with obesity prevalence lower than 20% was Colorado (18.6%) Increasingly also global problem Similar epidemics underway in both developed and developing countries More than half a billion people overweight by 2002

9 Obesity in children may portend accelerating future growth Between 1980 and 2000, the prevalence of overweight in children doubled Currently almost 1 in 3 school-age children overweight or obese in the US Once obesity exists, entrenched behaviors and tenacious physiological processes resist weight loss The majority of obese children (and >70% of adolescents who are overweight) become obese adults; a minority of currently obese adults were obese as children

10 Tip of the iceberg? Rise in overweight among US children Prevalence of overweight in US children and adolescents, by gender and age; SOURCE: Wang & Beydoun 2007, data from NHNES

11 Heterogeneity and Disparities Substantial heterogeneity in incidence of overweight/obesity Geographic

12 County-level Estimates of Obesity among Adults aged 20 years United States 2008 Age-adjusted percent > 30.8

13 Heterogeneity and Disparities Substantial heterogeneity in incidence of overweight/obesity Geographic Gender, race, income

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15 Heterogeneity and Disparities Substantial heterogeneity in incidence of overweight/obesity Geographic Gender, race, income Education (and gender) No significant link between obesity and education among men Among women, those with college degrees less likely to be obese compared with less educated women.

16 Impact

17 Public Health Impact Coronary heart disease: 50% more likely in overweight, twice as likely for obese, three times more likely in severely obese (BMI > 33) Type 2 diabetes: Obese women nearly twice as likely to develop Type 2 diabetes than those with BMI < 22 Hypertension risk in overweight increased 3.0 times (men) and 2.9 times (women) Blood pressure increase of 1 mmhg (systolic) per oneunit increase BMI among healthy adults aged Overweight and obesity also increase risks of: Cancers (endometrial, breast, and colon) Stroke, liver and gallbladder disease Osteoarthritis, sleep apnea, asthma

18 % Obese Example: Diabetes & Obesity By US County (2008) % Type II Diabetic

19 Economic Impact Economic costs associated with obesity epidemic in the United States may be as high as $215 bn annually At least three major sources of cost have been well quantified: Direct (health care) costs Indirect (productivity) costs Transportation costs Some evidence for other costs as well, less easy to measure

20 Direct Costs Obesity-attributable medical spending already accounts for 10% of all US health care costs (as high as $147 bn in direct costs annually) These have doubled in the last decade Some projections show dramatic future increases Private payers bear the majority of estimated costs, but public-sector spending is substantial Medicare spending would be an estimated 8.5% lower in the absence of obesity, Medicaid 11.8% lower

21 Indirect Costs Obesity-related health problems contribute to workplace absenteeism, presenteeism Obesity may lead to an increase in disability payments Indirect costs to US businesses include health insurance expenditures, paid sick leave, life insurance, and disability insurance Premature mortality affects population productivity Total productivity costs of obesity estimated to be as high as $66 bn annually

22 Transportation Costs Significant impact on transportation costs and environmental impact Moving heavier passengers takes more fuel: Airlines: weight gain during the decade of the 1990s alone required approximately 350 million extra gal of jet fuel in the year 2000 ($1.2 billion annually at today s fuel prices) Roads: Excess fuel consumption due to obesity by noncommercial passenger highway travel was estimated at one billion in 2009 ($2.7 billion annually at today s prices) Moving more food, more waste, larger products also takes more fuel (no estimate yet) Increased fuel use also has environmental, trade implications

23 Total Quantified Current Costs (up to $215 bn annually) Annual Cost Breakdown Direct Medical Spending ($86 - $147 billion) Indirect Productivity Costs ($5 - $66 billion) Transportation Costs ($3.7 - $3.9 billion) + Other costs: Educational effects, changes in facilities,.

24 Future Increases Rapid increase in childhood obesity likely to mean much higher costs in the future Onset of obesity-related health problems at younger ages means higher lifetime costs: Costs for medical treatments start earlier Productivity costs accumulate over longer period Higher obesity earlier in life also means a larger segment of the population contributing to obesity-related transportation costs There may be educational effects associated especially with school-age obesity

25 Age decade by which >20% cohort obese 60 Onset of widespread obesity at earlier ages

26 Complexity

27 The Obesity Epidemic as a Complex System Several characteristics make the obesity especially challenging to study, and to design interventions to slow or reverse Many interacting factors at several levels of scale Intra-individual: genetics, neurobiology, metabolism Social: family structure, norms, advertising, physical environment, agricultural markets, policy incentives Multiple actors Families, schools, retailers, industry, government, media, healthcare providers, city planners, employers, insurance Each has different goals, incentives, and constraints; interventions affect each in a different way Diversity Opportunities to become obese at many different ages across lifecourse, driven by potentially different factors

28 Implications of complexity for science and for policy There may be no single explanation for what is causing the epidemic There may be no single solution that fits all circumstances and contexts Interventions that do not take account of complexity in system can have unanticipated consequences Interventions that are successful in one area alone may be offset by response elsewhere in the system The most powerful interventions may be those that simultaneously address both individuals and their environment, at multiple levels, and in an integrated way

29 Research, data, and policy needs Increasing calls for new kinds of data, and systems research approaches that capture complexity and effectively inform policy choices 2010 IOM Report (and numerous scientific papers) calling for systems perspective and tools Newly formed research network in NIH/CDC/USDA /RWJF NCCOR for application of systems approaches to childhood obesity, discovery of novel intervention strategies Need for engagement, discourse with policymakers; a two-way conversation

30 Obesity: Trends, Impact, Complexity Ross A. Hammond, Ph.D. Director, Center on Social Dynamics & Policy Senior Fellow, Economic Studies Program The Brookings Institution