Stricter Mediterranean diet lowers risk for dementia

People who adhered more closely to the Mediterranean diet had a lower risk for dementia, regardless of genetic risk, according to data published in BMC Medicine.

Oliver M. Shannon, PhD, MSc, a lecturer in human nutrition and aging at Newcastle University in Newcastle upon Tyne, England, and colleagues identified 60,298 participants from the ongoing U.K. Biobank study who self-reported white British, Irish or other white race and were aged 60 years or older at enrollment. Additional inclusion criteria were appropriately reported dietary data, genetic data and complete covariate history.

Participants completed the self-administered Oxford WebQ at baseline between April 2009 and September 2010, and up to four more times between February 2011 and June 2012, to assess adherence to the Mediterranean diet. Adherence was measured with the Mediterranean Diet Adherence Screener (MEDAS) and the Mediterranean diet Pyramid.

A polygenic risk score was used to identify each participant’s risk for dementia. Incidence of dementia was assessed through linked inpatient and death records.

Greater adherence to the Mediterranean diet decreased the absolute risk for dementia. Based on MEDAS scores, the absolute risk for dementia was 1.73% with low adherence, 1.5% with medium adherence and 1.18% with high adherence. Pyramid scores indicated that the absolute risks for dementia with low, medium and high adherence were 1.67%, 1.53% and 1.21%, respectively.

Polygenic scores were positively associated with dementia (HR = 1.224; 95% CI, 1.102-1.36). However, there were no significant interactions between polygenic risk for dementia and adherence to the Mediterranean diet on either the MEDAS or the Pyramid.

“These results underline the importance of dietary interventions in future dementia prevention strategies regardless of genetic predisposition,” Shannon and colleagues wrote.