Effects of Changes in Physical Activity with Cognitive Decline in Korean Home-Dwelling Older Adults

The rapidly increasing older adults' population of South Korea has increased the socioeconomic burden on society due to cognitive decline. In this study, we examined the association between changes in physical activity in the older adults and their cognitive function, a primary criterion for the diagnosis of dementia, using panel data from the 2012-2018 Korean Longitudinal Study of Aging.

This study used baseline (2012) and biennial assessment of follow-up data (2014, 2016, 2018) from Korean Longitudinal Study of Aging. A total of 1733 older adults with the Korean version of the Mini Mental State Examination (K-MMSE) scores in the normal range at the time of the first investigation were included in the study. Physical activity was classified into three categories: inactivity, low physical activity, and high physical activity. Changes in physical activity from 2012 were classified into five groups: remained active, became active in 2016, became active in 2014, became inactive, and remained inactive. Participants' general and health-related characteristics were used as control variables. Descriptive statistics, chi-square tests, and logistic regression analysis were used for analysis.

The baseline mean age of the older adults in 2012 was 71.63 years; of the total 1733 participants, 57.1% were inactive, 5.7% had low physical activity, and 37.3% had high physical activity. Changes in physical activity were significantly associated with cognitive decline. Compared to the group that continued regular physical activity, the risk of cognitive decline increased in the case of participants who became or remained inactive.

Results highlighted the importance of continuous physical activity and its relation to cognitive function. Encouraging continuous physical activity in the older adults has a positive effect on the prevention of cognitive impairment and dementia. Thus, exercise-based interventions should be implemented a community health service.