Discussion
Alzheimer’s disease, dementia, Heras
Results from this randomized controlled trial provide preliminary evidence that BDNFval66met genotype interacts with biological sex to influence AT efficacy on executive functions in older adults with SIVCI, a clinical population with increased dementia risk. Specifically, we found that engaging in 6 months of AT compared with usual care and education control led to improvements on the Trail Making test (set-shifting) and Digit Symbol Substitution Test (working memory, sustained attention, and processing speed) in female Val/Val carriers. AT decreased performance on the set-shifting test in male Val/Val carriers and decreased performance on the working memory, sustained attention and processing speed test in female Met carriers compared with control.While the evidence for engaging in exercise to promote cognition is mounting [Our findings regarding the effect of AT on executive functions in Val/Val carriers are in line with prior observational studies that found the association between physical activity and executive functions was mainly evident in Val/Val carriers, though biological sex was not examined in these studies. For example, on tests of the executive function of conflict resolution, Val/Val carriers that were physically active performed better than inactive Val/Val carriers [As outlined by de las Heras and colleagues [Previous work suggests that the effect of BDNFval66met polymorphism on hippocampal blood flow, age-related cognitive and brain volume decline, and Alzheimer’s disease risk is sex-dependent [