This study aimed to investigate the association between abdominal adiposity and change in cognitive function in community-dwelling older adults.

This longitudinal study included older adults aged ≥60 years without cognitive impairment who participated in the National Institute for Longevity Sciences – Longitudinal Study of Aging.

Cognitive function was evaluated biennially using the Mini-Mental State Examination (MMSE) over 10 years. Waist circumference (WC) was measured at the naval level, and subcutaneous fat area (SFA) and visceral fat area (VFA) were assessed using baseline computed tomography scans. WC, SFA, and VFA areas were stratified into sex-adjusted tertiles. A linear mixed model was applied separately for men and women.

This study included 873 older adults. In men, the groups with the highest levels of WC, SFA, and VFA exhibited a greater decline in MMSE score than the groups with the lowest levels (β [95% confidence interval]: WC, –0.12 [–0.23 to –0.01]; SFA, –0.13 [–0.24 to –0.02]; VFA, –0.11 [–0.22 to –0.01]). In women, the group with the highest level of WC and SFA showed a greater decline in MMSE score than the group with the lowest level (WC, –0.12 [–0.25 to –0.01]; SFA, –0.18 [–0.30 to –0.06]), but VFA was not associated with cognitive decline.

Higher WC, SFA, and VFA in men and higher WC and SFA in women were identified as risk factors for cognitive decline in later life, suggesting that abdominal adiposity involved in cognitive decline may differ according to sex.