Abstract
Objectives
Although some results are conflicting, numerous investigations have demonstrated that
the Mediterranean Diet (MedDiet) has positive effects on brain health. This review
intends to provide an update on the scientific evidence regarding the effects of adherence
to the MedDiet on late-life cognitive disorders.
Design
A systematic review was performed. The PubMed and Scopus databases were searched for
longitudinal studies and randomized controlled trials (RCTs) published between the
databases’ inceptions and May 4, 2020. PRISMA guidelines were followed; the quality
of the studies was assessed using version 2 of the Cochrane risk-of-bias tool for
the RCTs and the Newcastle-Ottawa Scale for the longitudinal studies. The results
are reported descriptively.
Settings and Participants
Middle-aged and older adults.
Measures
The review's principal outcomes were cognitive decline, cognitive performance and
function, Mild Cognitive Impairment (MCI), Alzheimer's disease (AD), and dementia.
Results
Forty-five of the 995 articles retrieved from the databases met our criteria. Seven
were RCTs and 38 were longitudinal studies. Overall the studies showed that the MedDiet
has some protective effects on cognitive decline. As far as cognition domains were
concerned, the MedDiet was associated only with improved global cognition. The results
were mixed for MCI and AD. There was no evidence that it has a beneficial effect on
dementia.
Conclusions and Implications
The review's analysis confirmed that adherence to the MedDiet is associated with some
improvement in cognitive health. The heterogeneity of the scoring systems assessing
adherence to the MedDiet and of the modalities evaluating the cognitive outcomes has
played no small role in the differences emerging in the results and has hindered efforts
to interpret them. Although other interventional studies are warranted to confirm
the efficacy of the MedDiet in preventing cognitive disorders, the results show that
it can be considered part of a multifactorial approach to improve late-life cognitive
function.
Keywords
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Article info
Footnotes
F.L. and P.S. contributed equally to the study.
The authors declare no conflicts of interest.
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© 2020 AMDA - The Society for Post-Acute and Long-Term Care Medicine.
