Association of Mediterranean diet with mild cognitive impairment and Alzheimer's disease

A systematic review and meta-analysis

Balwinder Singh, Ajay K. Parsaik, Michelle M. Mielke, Patricia J. Erwin, David S. Knopman, Ronald C. Petersen, Rosebud O. Roberts

Research output: Contribution to journalArticle

Abstract

Background/Objective: To conduct a systematic review of all studies to determine whether there is an association between the Mediterranean diet (MeDi) and cognitive impairment. Methods: We conducted a comprehensive search of the major databases and hand-searched proceedings of major neurology, psychiatry, and dementia conferences through November 2012. Prospective cohort studies examining the MeDi with longitudinal follow-up of at least 1 year and reporting cognitive outcomes (mild cognitive impairment [MCI] or Alzheimer's disease [AD]) were included. The effect size was estimated as hazard-ratio (HR) with 95% confidence intervals (CIs) using the random-effects model. Heterogeneity was assessed using Cochran's Q-test and I2-statistic. Results: Out of the 664 studies screened, five studies met eligibility criteria. Higher adherence to the MeDi was associated with reduced risk of MCI and AD. The subjects in the highest MeDi tertile had 33% less risk (adjusted HR = 0.67; 95% CI, 0.55-0.81; p <0.0001) of cognitive impairment (MCI or AD) as compared to the lowest MeDi score tertile. Among cognitively normal individuals, higher adherence to the MeDi was associated with a reduced risk of MCI (HR = 0.73; 95% CI, 0.56-0.96; p = 0.02) and AD (HR = 0.64; 95% CI, 0.46-0.89; p = 0.007). There was no significant heterogeneity in the analyses. Conclusions: While the overall number of studies is small, pooled results suggest that a higher adherence to the MeDi is associated with a reduced risk of developing MCI and AD, and a reduced risk of progressing from MCI to AD. Further prospective-cohort studies with longer follow-up and randomized controlled trials are warranted to consolidate the evidence. Systematic review registration number: PROSPERO 2013: CRD42013003868.

Original languageEnglish (US)
Pages (from-to)271-282
Number of pages12
JournalJournal of Alzheimer's Disease
Volume39
Issue number2
DOIs
StatePublished - 2014
Externally publishedYes

Fingerprint

Mediterranean Diet
Meta-Analysis
Alzheimer Disease
Confidence Intervals
Cohort Studies
Prospective Studies
Cognitive Dysfunction
Neurology
Psychiatry
Dementia
Randomized Controlled Trials
Databases

Keywords

  • Alzheimer's disease
  • Mediterranean diet
  • meta-analysis
  • mild cognitive impairment
  • systematic review

ASJC Scopus subject areas

  • Psychiatry and Mental health
  • Geriatrics and Gerontology
  • Clinical Psychology

Cite this

Singh, B., Parsaik, A. K., Mielke, M. M., Erwin, P. J., Knopman, D. S., Petersen, R. C., & Roberts, R. O. (2014). Association of Mediterranean diet with mild cognitive impairment and Alzheimer's disease: A systematic review and meta-analysis. Journal of Alzheimer's Disease, 39(2), 271-282. https://doi.org/10.3233/JAD-130830

Association of Mediterranean diet with mild cognitive impairment and Alzheimer's disease : A systematic review and meta-analysis. / Singh, Balwinder; Parsaik, Ajay K.; Mielke, Michelle M.; Erwin, Patricia J.; Knopman, David S.; Petersen, Ronald C.; Roberts, Rosebud O.

In: Journal of Alzheimer's Disease, Vol. 39, No. 2, 2014, p. 271-282.

Research output: Contribution to journalArticle

Singh, Balwinder ; Parsaik, Ajay K. ; Mielke, Michelle M. ; Erwin, Patricia J. ; Knopman, David S. ; Petersen, Ronald C. ; Roberts, Rosebud O. / Association of Mediterranean diet with mild cognitive impairment and Alzheimer's disease : A systematic review and meta-analysis. In: Journal of Alzheimer's Disease. 2014 ; Vol. 39, No. 2. pp. 271-282.
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