Disability associated with obesity, dynapenia and dynapenic-obesity in Chinese older adults

Whether the combination of obesity and low muscle strength (dynapenic-obesity) would cause greater impairment of the activities of daily living (ADL)/instrumental activities of daily living (IADL) than obesity alone and low muscle strength alone (dynapenia) remains unclear. The aim of this study was to reveal the possible independent and additive effects of dynapenia and obesity on ADL/IADL disability in an older Chinese population.

A cross-sectional study, including 616 community-dwelling older adults, was conducted in China from 2010 to 2012. Based on the World Health Organization Asian Criteria of Obesity and handgrip strength tertiles, 4 independent groups were identified as follows: nondynapenia/nonobesity, dynapenia alone, obesity alone, and dynapenic-obesity. The Katz Index of Independence in ADL was used to assess ADL disability, whereas 6 IADL items of the Older Americans Resources and Services (OARS) multidimensional functional assessment questionnaire were used to assess IADL disability.

The prevalence of ADL and IADL disability was 21.1% and 28.9% in the dynapenic-obesity group, 15.5% and 22.6% in the dynapenia alone group, 13.1% and 19.6% in the obesity alone group, and 11.9% and 12.9% in the nondynapenia/nonobesity group, respectively. After adjusting for the covariates, in comparison with the dynapenic-obesity group, the adjusted odds ratios (95% confidence interval) for ADL disability were 0.36 (0.13-0.73) in the nondynapenia/nonobesity group, 0.51 (0.20-0.78) in the dynapenia-alone group, and 0.40 (0.11-0.61) in the obesity-alone group. The corresponding data for IADL disability were 0.55 (0.20-0.93), 0.82 (0.39-0.98), and 0.61 (0.30-0.91), respectively.

Dynapenia, obesity, and dynapenic-obesity were associated with an increased risk of ADL/IADL disability. Dynapenic-obesity was associated with a greater risk of ADL/IADL disability in comparison with dynapenia or obesity alone.