Dynapenic abdominal obesity and incident functional disability: results from a nationwide longitudinal study of middle-aged and older adults in China

There is little epidemiological evidence on the relationship of dynapenic abdominal obesity (DAO) and the development of functional disability, particularly in Asian populations. We aimed to investigate the association of DAO with new-onset functional disability in Chinese adults. A total of 7881 participants aged ≥45 years from China Health and Retirement Longitudinal Study (CHARLS) in 2011 and 2015 were included in the study. Dynapenia and abdominal obesity were respectively defined based on handgrip strength (< 28 kg for male and < 18 kg for female) and waist circumference (≥ 90 cm for male and ≥ 85 cm for female). The sample was divided into four groups: non-dynapenic/non-abdominal obesity (ND/NAO), non-dynapenic/abdominal obesity (ND/AO), dynapenic/non-abdominal obesity (D/NAO) and dynapenic/abdominal obesity (D/AO). Functional status was assessed by basic activities of daily living (BADL) or instrumental activities of daily living (IADL). Logistic regression model was used to explore the longitudinal association between dynapenic abdominal obesity and incident functional disability. After a 4-year follow-up, 1153 (14.6%) developed BADL disability and 1335 (16.9%) developed IADL disability. The multivariable-adjusted odds ratios (95% CIs) for the D/AO versus ND/NAO were 2.21 (1.61-3.03) for BADL disability, and 1.68 (1.23-2.30) for IADL disability. In addition, DAO was associated with an increased risk for functional dependency severity (odds ratio, 2.08 [95% CI, 1.57-2.75]). DAO was significantly associated with greater risk of functional disability among Chinese middle-aged and older adults. Our findings indicated that interventions targeted DAO might be effective in the primary prevention of functional disability.