Physical activity and functional status in older adults: Mediating effect of cognitive function

Abstract

AbstractBackgroundOlder adults who participate in social activities have more active lifestyles which has been shown to improve their quality of life (Acree et al., 2006). Generally instrumental activities of daily living (IADL) require aspects of social participation (e.g., cooking and managing finances) (Guo & Sapra, 2020). A previous study reported that physical and cognitive functions are positively associated with functional status in IADLs (Yam & Marsiske, 2013). In addition, since physical activity is associated with cognitive function, active participation in physical activity is recommended to maintain and improve cognitive function. While a number of studies have investigated the relationship between physical activity, cognitive function, and IADL, it is not clear if cognitive function acts as a mediator between physical activity and functional status equation. The aim of this study was to examine the relationship between physical activity and IADL and to clarify the mediating effect of cognitive function.MethodA retrospective cross‐sectional design that analyzed the association between physical activities and IADL and the mediating effects of cognitive function. We retrieved 3,980 people from the 6 million recipients eligible for the Korean health insurance and benefits, between years 2002 and 2015. The included people in this analysis are 60 years and older and have completed the physical activity questionnaire. We estimated the indirect effect of physical activities through cognitive function on IADL performance.ResultThe average age of the participants was 81.6 years (SD = 5.5), and 72.74% were female. There were a direct effect of high‐intensity exercise on IADL (β = 0.04, 95% CI: 0.01, 0.07) and an indirect effect of high‐intensity exercise through cognitive function (β = 0.05; 95% CI: 0.04, 0.07). In addition, there were a direct effect of moderate‐intensity exercise and IADL (β = 0.04, 95% CI: 0.01, 0.07) and an indirect effect of moderate‐intensity exercise through cognitive function (β = 0.05; 95% CI: 0.04, 0.07).ConclusionThe study indicated that there were positive relationships between physical activities, cognitive function and IADL. In addition, there was a mediating effect of cognitive function on the relationship between physical activities and IADL.