Associations of anthropometric measures of obesity with physical limitations in older adults

Introduction: Physical limitations are associated loss of independence, lower quality of life, greater healthcare costs, and mortality. Changes in body composition during the aging process contribute to the decline in physical functioning. Body mass index is commonly used to quantify adiposity; however, measurements that better capture abdominal obesity may confer better advantage for risk of physical limitations. Methods: We used data from the 2013-2014 National Health and Nutrition Examination Survey to compare the associations of (1) body mass index, (2) sagittal abdominal diameter, and (3) waist circumference with physical limitations in adults 60-80 years (n = 1258). We used weighted logistic regression models to allow for estimates that are representative of the US population. Results: All three anthropometric measures were significantly associated with physical limitations. Abdominal fat measurements (sagittal abdominal diameter and waist circumference) were more strongly associated with physical limitations in men. However, they were not independently associated with physical limitations after controlling for body mass index. All three measurements did not differ in their ability to distinguish presence of physical limitations. Conclusions: Our data suggest that abdominal fat measurements are not independently associated with physical limitations after accounting for body mass index. Body mass index, waist circumference, and sagittal abdominal diameter are all of equal practical value for identifying older adults at risk for physical limitations.