Dietary Patterns and Risk of Dementia in Elderly Individuals: A Systematic Review and Meta-analysis of Cohort Studies.

Context: Three healthy dietary patterns-the Mediterranean (MED) diet, the Dietary Approaches to Stop Hypertension (DASH) diet, and the Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diet-have all been recognized to show potential protective effects against dementia, but the results are inconclusive.

Objective: The present study investigated the associations between the 3 healthy dietary patterns and risk of dementia in elderly individuals through a systematic review and meta-analysis.

Data sources: PubMed, Web of Science, Embase, and Scopus databases were searched up to April 12, 2024.

Data extraction: A total of 12 studies, involving 14 cohorts, were included.

Data analysis: Hazard ratios (HRs) and 95% CIs for the highest vs lowest category of dietary adherence were pooled using a random-effects model. Subgroup analyses and meta-regression were performed to identify the potential sources of heterogeneity. The pooled HR in the MED diet was 0.85 (95% CI: 0.71-1.03) based on 51 581 participants, while in the DASH diet and the MIND diet with 36 123 and 18 328 participants, the pooled HRs were 0.80 (95% CI: 0.60-1.06) and 0.78 (95% CI: 0.68-0.89), respectively. In the subgroup analysis, the pooled HRs for the MED diet were 0.72 (95% CI: 0.55-0.93) when the follow-up duration was 10 years or less, and 0.63 (95% CI: 0.48-0.82) when the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) criteria were used.

Conclusion: Adherence to the MIND diet could be an effective nonpharmacological measure to reduce the risk of dementia among the elderly.

Systematic review registration: PROSPERO registration no. CRD42024532389.