LIFETIME EXERCISE HABITS AND MILD COGNITIVE IMPAIRMENT IN LATE LIFE AMONG COMMUNITY-DWELLING OLDER ADULTS

K. Makino¹, S. Lee¹, K. Harada¹, O. Katayama¹, K. Tomida¹, M. Morikawa¹, R. Yamaguchi¹, C. Nishijima¹, K. Fujii¹, Y. Misu¹, H. Shimada¹

¹National Center for Geriatrics and Gerontology, Department of Preventive Gerontology, Obu, Japan

Background: Habitual exercise is a major protective factor against dementia. Regular exercise, not only in late life but also in mid or early life, is reportedly beneficial for cognitive function in late life. However, cognitive function assessment scales differ among previous studies, and their findings are incongruent. In addition, the relationship between changes in exercise habits across life stages and cognitive function in late life has not been fully examined.

Purpose: This study aimed to examine the association between exercise habits at each life stage, changes in exercise habits, and mild cognitive impairment (MCI) in late life, based on a multi-domain cognitive assessment.

Methods: A total of 4,571 community-dwelling people without dementia, aged ≥65 years (mean age 73.7±5.5 years, 44.9% male), met the inclusion criteria for this study. We retrospectively assessed their exercise frequency at three life stages (early life: 25–44 years; mid life: 45–64 years; late life: ≥65 years), defining exercise habit as exercising at least twice a week for each life stage. Based on changes in exercise habits, we categorized participants into five groups: non-exercisers (those without exercise habits during all life stages), new exercisers (those who acquired exercise habits at mid or late life), dropouts (those who lost exercise habits at mid or late life), maintainers (those with exercise habits during all life stages), and others (those who experienced both the loss and acquisition of exercise habits). Cognitive assessment was conducted using a multi-domain neurocognitive test including memory, attention, executive function, and processing speed. Impairment in one or more cognitive domains was defined as MCI. Age, sex, education level, chronic diseases, gait speed, depressive symptoms, smoking status, and living alone were also assessed as covariates.

Results: Exercise habits were observed in 24.7% participants in early life, 27.4% in mid life, and 29.2% in late life. MCI prevalence in late life was 17.3%. Logistic regression analysis showed that exercise habits in mid life (OR: 0.71; 95% CI: 0.59–0.86) and late life (OR: 0.81; 95% CI: 0.67–0.97) were significantly associated with lower MCI prevalence in late life after adjusting for covariates, but exercise habits in early life (OR: 0.85; 95% CI: 0.70–1.03) were not. Regarding changes in exercise habits and MCI risk, compared to non-exercisers, new exercisers (OR: 0.79; 95% CI: 0.63–0.98) and maintainers (OR: 0.72; 95% CI: 0.54–0.97) were significantly associated with lower MCI prevalence in late life, while drop-outs (OR: 0.84; 95% CI: 0.65–1.07) and others (OR: 0.71; 95% CI: 0.47–1.07) were not.

Conclusions: Exercise habits at mid and late life were associated with reduced MCI risk in late life. Furthermore, although maintaining exercise habits throughout the lifespan is an optimal approach, acquiring new exercise habits in mid or late life may also be beneficial in preventing MCI. Further studies with prospective longitudinal data are required to corroborate our findings.

Implications: These results indicate the importance of supporting exercise habituation from earlier life stages as a preventive physiotherapy approach, for maintaining cognitive function as well as physical function.

Funding acknowledgements: This work was supported by JSPS KAKENHI (grant number 20J01647 and 22K11413).

Keywords:
Regular exercise
cognitive impairment
older adults

Topics:
Health promotion & wellbeing/healthy ageing/physical activity
Older people
Community based rehabilitation

Did this work require ethics approval? Yes

Institution: National Center for Geriatrics and Gerontology

Committee: Ethics committee of the National Center for Geriatrics and Gerontology

Ethics number: 1440-3