Association between dietary diversity and cognitive impairment in community‐dwelling older adults

Abstract

AbstractBackgroundMild cognitive impairment (MCI) is an intermediate state between normal cognitive aging and dementia, and it is a target population for interventions in dementia prevention. Dietary diversity is associated with the risk of dementia. However, the association between dietary diversity and MCI, remains unclear. The present study aimed to examine whether dietary diversity is associated with cognitive impairment, including MCI, in community‐dwelling older Japanese adults.MethodThis cross‐sectional study was conducted using data from the National Center for Geriatrics and Gerontology Study of Geriatric Syndromes. MCI and global cognitive impairment (GCI) were assessed using the Mini‐Mental State Examination and National Center for Geriatrics and Gerontology‐Functional Assessment Tool (NCGG‐FAT), which are multicomponent neurocognitive tests that include memory, attention, executive function, and processing speed. Participants with one or more cognitive decline were defined as having MCI. Dietary diversity was assessed using the diet variety score (DVS). DVS assessed the one‐week consumption frequency of ten food groups and either 0 or 1 point was allocated to each category based on the following responses: (1) “eat almost every day” (1 point), (2) “not eaten almost daily” (0 points). Older adults with a DVS of 3 or more points were defined as having high dietary diversity.ResultData included 8,987 older adults (mean age: 73.9 ± 5.5 years; men: 44.3%). The overall prevalence of MCI and GCI followed; 17.1% (n = 1,538) and 8.4% (n = 753), respectively. The proportion of patients with a high dietary diversity was 69.9% (n = 6,286). Multinomial logistic regression analysis revealed high dietary diversity was associated with MCI (OR 0.83, 95% CI 0.73‐0.94) and GCI (OR 0.77, 95% CI 0.65‐0.92) after adjusting for covariates.ConclusionThis study showed that high dietary diversity was associated with a lower proportion of MCI and GCI among older adults. Ingesting a wide variety of foods contributes to the enhancement of cognitive function among older adults.