Obesity and functional disability in elderly Americans

OBJECTIVES: To investigate whether indicators of obesity are associated with functional disabilities in elderly American women and men. DESIGN: Cross-sectional. SETTING: National Health and Nutrition Examination Survey (NHANES) 1999 to 2004, United States. PARTICIPANTS: One thousand six hundred eighty-four elderly (aged >= 60) women and 1,611 elderly men. MEASUREMENTS: Functional disabilities. RESULTS: In women, body mass index (BMI) and waist circumference were each related to higher prevalence of all measures of disabilities. Compared with the lowest quartile of waist circumference, the multivariate odds ratios (ORs) of the highest quartile for having difficulties in functional domains were 2.4 (95% confidence interval (CI)=1.6-3.6) for activities of daily living, 2.3 (95% CI=1.6-3.3) for instrumental activities of daily living, 2.6 (95% CI=1.6-4.1) for leisure and social activities, 4.8 (95% CI=3.4-6.9) for lower extremity mobility, and 2.9 (95% CI=2.1-4.0) for general physical activity. In men, these associations were moderate; the corresponding ORs were 1.2 (95% CI=0.8-2.0), 1.3 (95% CI=0.9-2.1), 2.1 (95% CI=1.2-3.7), 1.8 (95% CI=1.2-2.7), and 2.1 (95% CI=1.5-2.8), respectively. Similar results were obtained for BMI. These associations could not be explained by the presence of major chronic conditions. When adjusted simultaneously, waist circumference appeared to be a better predictor than BMI of disability in women. CONCLUSION: The results suggest that indicators of obesity are related to functional disabilities in elderly Americans.