Peripheral Alzheimer's Disease Biomarkers Are Related to Change in Subjective Memory in Older Women with Cardiovascular Risk Factors in a Trial of Yoga vs. Memory Training: Lien établi entre les biomarqueurs périphériques de la maladie d'Alzheimer et l'amélioration de la mémoire subjective chez les femmes âgées présentant des facteurs de risque cardiovasculaire dans le cadre d'un essai comparant le yoga à l'entraînement de la mémoire.

Abstract

ObjectivesOlder women with cardiovascular risk factors and subjective memory complaints are at greater risk for Alzheimer's disease (AD). We examined the changes in AD peripheral biomarkers, including phosphorylated-tau (p-tau), Aβ40, Aβ42, and Aβ42/40 ratio, in a randomized controlled trial of Kundalini yoga (KY) versus memory enhancement training (MET) in aging women at risk for AD.MethodsWe recruited women (50+ years) with subjective memory complaints and high cardiovascular risk as defined by the ACC/AHA Guideline on the Assessment of Cardiovascular Risk. Participants were randomized into KY versus MET, each lasting for 12 weeks, with a 24-week follow-up. We obtained blood samples at baseline and week 24 and measured Aβ 40, Aβ 42, and p-Tau. Participants completed the Memory Functioning Questionnaire (MFQ) to assess subjective memory at baseline and follow-up.ResultsA total of 79 patients (KY = 40; MET = 39) were randomized, and biomarker data were available for 56 participants (KY = 24; MET = 32) at baseline and the 24-week follow-up. There were no group differences in AD biomarkers at baseline or at 24-week follow-up, and there were no significant changes in AD biomarkers from baseline to 24-week follow-up. Higher baseline levels of Aβ40 and Aβ42 were significantly associated with an improvement in subjective memory (MFQ Frequency of Forgetting and Seriousness of Forgetting) at follow-up. There was no significant association of the Aβ42/40 ratio and p-tau with changes in subjective memory.ConclusionsOur findings indicate that peripheral Aβ40 and Aβ42 levels are associated with improvement in memory self-awareness, particularly the reported frequency and perceived severity of forgetting. These levels may serve as potential biomarkers, reflecting underlying biological effects that could be utilized in future assessments. Further research is needed to determine how to successfully utilize peripheral biomarkers and subjective memory complaints to identify at-risk populations.