[Effect of physical exercise on Alzheimer's disease. A sistematic review].

Objective: The objective of this review is to analyze through a the scientific evidence about the effects of physical activity in patients with Alzheimer's disease (AD) as a preventive and non-pharmacological treatment.
Design: Systematic review.
Data Sources: We have identified articles from Pubmed, Science Direct, Medline and Scopus databases, with the keywords Alzheimer, Exercise, Neuroimaging, MRI, PET y Physical Activity. Selected articles: We included those studies that evaluated the effects of physical activity on Alzheimer's disease and those which also included magnetic resonance imaging or positron emission tomography with Pittsburg Compound B marker (PiB) analyzing brain atrophy or increase of the beta-amyloid deposit respectively. We excluded studies including other types of dementia, different of AD. We also excluded articles which not included neuroimaging tests, single cases or non-English language articles.
Data Extraction: The PRISMA quality scale was used for the critical lecture of the studies. The researchers independently assessed the articles and the discrepancies were resolved by consensus.
Results: We identified 75 articles, of which 23 were finally included in the review.
Conclusions: Most of the studies included do not allow us to know the impact of physical exercise on cognition and the cerebral structural-functional changes in patients at risk of developing AD or in patients who already have the disease. Without being able to rule out a possible beneficial effect, more studies are needed with a better design and methodological rigor that allows a better known about this association.
(Copyright © 2018 The Authors. Publicado por Elsevier España, S.L.U. All rights reserved.)