Associations of dietary patterns with mild cognitive impairment in older Singaporean adults: findings from the diet and healthy aging cohort

BACKGROUND: As the global population ages, the prevalence of mild cognitive impairment (MCI) and dementia is increasing substantially. Studies conducted predominantly in Western populations suggest that adherence to healthy dietary patterns may help preserve cognitive health. However, evidence in Asian populations remains limited and inconsistent. OBJECTIVE: To investigate the cross-sectional and longitudinal associations between adherence to the alternate Mediterranean diet (aMED), Dietary Approaches to Stop Hypertension (DASH), and Healthy Diet Indicator (HDI) dietary patterns and odds of MCI among older Singaporean adults. DESIGN: Cross-sectional and longitudinal analyses of data from the Diet and Healthy Aging cohort. SETTING: Community-dwelling older adults in Singapore. PARTICIPANTS: A total of 620 older adults (mean age 67.7 ± 6.0 years; 71.8% women) were included in the cross-sectional analysis, while 313 cognitively normal participants were included in the longitudinal analysis. MEASUREMENTS: Dietary adherence scores were derived from a validated food frequency questionnaire. MCI was diagnosed using the Singapore-modified Mini-Mental State Examination (SM-MMSE), Clinical Dementia Rating (CDR), and a battery of standardized neurocognitive tests. Logistic regression models adjusted for potential confounders were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: In cross-sectional analyses, higher adherence to aMED, but not DASH or HDI, was associated with lower odds of MCI (OR = 0.35, 95% CI: 0.17-0.73, P-trend < 0.005). In longitudinal analysis, none of the dietary patterns were significantly associated with incident MCI. CONCLUSION: Higher adherence to aMED was associated with lower odds of MCI cross-sectionally, although no significant longitudinal associations were observed. Further prospective studies with larger sample sizes and repeated dietary assessments are needed to clarify the role of predefined dietary patterns in cognitive health among Asian older adults.