Leisure-time physical activity modulates associations of sarcopenia and functional disability with mortality in older adults.

Whether physical activity modifies the associations of sarcopenia and basic/instrumental activities of daily living (ADL/IADL) disability with mortality remains unclear. The study included 64,146 participants from three nationally representative cohorts: Health and Retirement Study (HRS), Survey of Health, Aging and Retirement in Europe (SHARE), and China Health and Retirement Longitudinal Study (CHARLS). In HRS, the greater risk of mortality associated with each dysfunction was more pronounced in inactive participants, with multivariable-adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) in Cox models of 3.88 (3.57-4.23) for sarcopenia, 1.82 (1.70-1.95) for ADL disability, and 1.95 (1.81-2.09) for IADL disability, while the corresponding HRs (95% CIs) were 3.32 (2.92-3.77), 1.39 (1.20-1.61), and 1.44 (1.26-1.65) in regularly active participants (all for multiplicative interaction < 0.010). Consistent interaction patterns were observed in SHARE and CHARLS. This study revealed that regular activity meeting the WHO recommendations significantly mitigated the hazards of mortality associated with sarcopenia and ADL/IADL disability.