The role of physical activity in the association between disability and mortality among US older adults: a nationwide prospective cohort study

To examine whether physical activity can mitigate the mortality risk associated with disability in activities of daily living and instrumental activities in daily living among older adults. This analysis comprised 177,360 US participants (104,556 women), aged ≥ 60 years, with valid data from the 1997 through 2018 waves of the US National Health Interview Survey. Participants reported the frequency and duration of leisure-time PA, and their disabilities in activities of daily living and instrumental activities in daily living. Mortality data were obtained from the National Death Index. Over a mean (SD) follow-up of 8.02 (5.43) years, 66,694 deaths occurred from all-cause, 22,673 from cardiovascular disease, and 13,845 from cancer. Among people with disability in activities in daily living, those reaching physical activity recommendations had 25%, 24% and 33% lower risk of all-cause mortality, cardiovascular diseases, and cancer death, respectively, compared with those who do not meet physical activity recommendations. Values were 23%, 22% and 24% for those with disability in instrumental activities in daily living. Risk reductions associated with reaching the recommended physical activity ranged 16% to 29% for people without disability. Combining disability type and compliance with physical activity, individuals with disability in activities of daily living or instrumental activities in daily living who meet the recommended physical activity had moderately higher mortality than those without disability who did not achieve the recommended physical activity. Compliance with physical activity recommendations can partially mitigate excess mortality resulting from disability in activities in daily living or instrumental activities in daily living in older adults.