Abstract
BACKGROUND: The health benefits of physical activity (PA) have been well recognized, while which types of PA are most beneficial are still unclear, especially for older adults. The study aimed to explore associations of different PAs (physical work, regular exercise, and leisure activities) with mortality among Chinese older adults, considering genetic risk. METHODS: A total of 9690 older adults from the Chinese Longitudinal Health Longevity Survey (CLHLS, 1998-2018) were included. Self-reported PAs information on physical work, regular exercise, and leisure activities were collected through face-to-face interviews. Leisure activities were interviewed about their engagement in 6 typical activities (i.e., housework tasks, personal outdoor activities, gardening, rearing domestic animals/pets, playing cards/mahjong, and attending in social activities). A weighted genetic risk score (GRS) was constructed based on 11 lifespan-related loci and divided into two groups according to the median scores (0.21). The Cox proportional risk model was used to assess the association between different types of PAs and genetic risk with all-cause mortality. RESULTS: During 63,832 person-years of follow-up, 5678 deaths were documented. The hazard ratios (HRs) for all-cause mortality between different PAs (lowest activity vs highest activity) were 0.85 (95% CI 0.79-0.92) for leisure activities, 0.93 (95% CI 0.87-0.99) for regular exercise, and 0.93 (95% CI 0.86-1.01) for physical work, respectively. Compared with low leisure activities, high leisure activities were associated with 16% reduction in all-cause mortality for individuals with low longevity GRS (HR 0.84, 95% CI 0.76-0.93), and 14% reduction in all-cause mortality for individuals with high longevity GRS (HR 0.86, 95% CI 0.78-0.96). Adherence to regular exercise was associated with 11% reduction in all-cause mortality for individuals with high longevity GRS (HR 0.89, 95% CI 0.81-0.97), while there was no statistically significance for those with low longevity GRS (HR 0.97, 95% CI 0.89-1.06) compared with those without regular exercise. There was no additive or multiplicative interaction between PAs and longevity genetics (P(interaction) > 0.05). CONCLUSIONS: Leisure activities, as a low-risk, low-intensity, simple and inexpensive PA, rather than regular exercise, might bring the greatest health benefits, even for individuals with less longevity genes, highlighting the importance of providing individualized PA recommendations for older adults.