Affiliation:
1. Integrated Research Initiative for Living Well with Dementia Tokyo Metropolitan Institute for Geriatrics and Gerontology Itabashi Tokyo Japan
2. Research Team for Promoting Independence and Mental Health Tokyo Metropolitan Institute for Geriatrics and Gerontology Itabashi Tokyo Japan
3. Department of Frailty Research, Center for Gerontology and Social Science Research Institute National Center for Geriatrics and Gerontology Obu Aichi Japan
4. Research Team for Social Participation and Community Health Tokyo Metropolitan Institute for Geriatrics and Gerontology Itabashi Tokyo Japan
5. Human Care Research Team Tokyo Metropolitan Institute for Geriatrics and Gerontology Itabashi Tokyo Japan
6. Tokyo Metropolitan Institute for Geriatrics and Gerontology Itabashi Tokyo Japan
Abstract
AimMuscle mass and strength correlate with cognitive function; however, it remains unclear whether dynapenia (i.e., muscle weakness with preserved muscle mass) is relevant. This study aimed to explore whether dynapenia is associated with global cognitive function in community‐dwelling older Japanese adults.MethodsThis cross‐sectional study used data from the Integrated Research Initiative for Living Well with Dementia Cohort Study, which pooled data from five community‐based geriatric cohorts. Dynapenia was defined as muscle weakness without muscle mass loss according to the Asian Working Group for Sarcopenia criteria. Cognitive function was assessed using the Mini‐Mental State Examination (MMSE). An ordered logistic regression analysis was conducted with dynapenia as the exposure and with cognitive decline stages, defined as an MMSE score of 27–30 for normal cognition, 24–26 for possible cognitive decline, and <24 for cognitive decline, as the outcome, stratified by sex and adjusted for age, muscle mass, education, alcohol consumption, smoking habits, living alone, and non‐communicable diseases.ResultsWe analyzed data for 3338 participants (2162 female) with preserved muscle mass. Of these, 449 (13.5%) had dynapenia, and 79 (2.4%) exhibited cognitive decline. Multivariate odds ratios (95% confidence interval) for cognitive decline among those with dynapenia, compared with those without dynapenia, were 1.51 (1.02–2.24) for males and 2.08 (1.51–2.86) for females.ConclusionsMuscle weakness is associated with cognitive decline, even in individuals with preserved muscle mass. Further studies are needed to better understand the association between muscle weakness and cognitive decline over time in order to develop dementia prevention strategies for those with dynapenia. Geriatr Gerontol Int 2023; ••: ••–••.