Data from the FIT-AD trial (NCT1954550) suggest a specific blood metabolite profile correlates with having improvement in Alzheimer’s disease (AD) cognitive symptoms in response to exercise. Of the participants in the FIT-AD trial, who all had AD, 26 agreed to have fasting blood samples taken before the intervention began and 12 months later. Using a commercially available metabolomics assay (Absolute IDQ p180 kit; Biocrates Life Sciences, Innsbruck, Austriea) blood plasma levels of 188 metabolites were assessed at baseline.
Participants were randomly assigned to have a 6-month intervention of moderately intense aerobic stationary cycling or anaerobic range of motion/stretching exercise, matched for time and attention. Participants were followed for 6 months after the intervention ended and all had cognitive testing at baseline, and 3, 6, and 12 months. Using multiple linear-regression models, 12-month changes in cognition, intervention used, and blood metabolite levels were examined for interactions with blood metabolite levels, after adjustment for age and sex. Through this analysis, 7 metabolites correlated with improved cognition in response to aerobic exercise at 12 months. Individuals who had cognitive improvements in response to exercise were more likely to have relatively higher levels of the phospholipid PC aa C40.6 and the amino acids isoleucine, leucine, methionine, tyrosine, and valine. Lower levels of the phospholipid lyso PC a C18.2 was also associated with improved cognition in response to exercise.
"Exercise treatment is a very promising intervention for Alzheimer's patients and is even an effective treatment for cognitive impairment in patients without Alzheimer's," said Danni Li, PhD, of the University of Minnesota in Minneapolis and colead of the study. "But we also know that not everyone responds to exercise in the same way, so we want to use this research to develop a test to see who is going to respond better to exercise treatment. This is in line with the model of precision medicine and finding the right person who will respond to the right therapy."
The researchers, led by Danni Li, PhD, and Fang Yu, PhD, of the University of Minnesota in Minneapolis, are presenting these results at the American Association for Clinical Chemistry (AACC) Annual Meeting in Anaheim, CA, August 4-8, 2019 note that a future study with larger sample size is needed to establish the validity of metabolite levels to predict cognitive responses to aerobic exercise treatment in AD.
Stanley Jones P. Iyadurai, MD, PhD, FAAN
Peter McAllister, MD
Michelle L. Dougherty, MD, FAAN, FAES