Physcial Exercise May Stall Cognitive Decline in Mild Cognitive Impairment

In the phase 3 EXERT trial (NCT02814526), 296 individuals, age 65 to 89, with amnestic mild cognitive impairment (MCI) who participated in supervised exercise programs maintained baseline cognitive abilities. Cognition was measured at baseline and after 12 months of supervised exercise with the Alzheimer Disease Assessment Scale-Executive function (ADAS-Exec) and the Clinical Dementia Rating Sum of Boxes (CDR-SB) measures. 

Participants were randomly assigned to complete supervised high-intensity exercise (heart rate 70% to 85% of capacity) or low-intensity stretching and balance exercise (heart rate < 35% of capacity). No differences were seen between these 2 groups. Compared with a group of people who received usual care, however, there was a significant relative difference. Those who had usual care had significant declines in ADAS-Exec (P=.012) and CDR-SB (P<.005) scores. The usual care cohort was matched to the intervention groups by age, sex, education, baseline cognition, and apolipoprotein ε4 (APOE ε4) status. 

Participants exercised at participating YMCAs located near the selected clinic sites across the US. In the first 12 months, a study-certified YMCA trainer supervised all participants for the first 8 exercise sessions completed (weeks 1 and 2), and for 2 of 4 weekly sessions thereafter through Month 12. Over 31,000 exercise sessions were completed. Adherence to the exercise program was evaluated by multiple mechanisms, including heart rate monitoring, participant ratings of perceived exertion, and participants' Physical Activity Logs. 

Laura Baker professor of internal medicine and neurology and public health sciences at Wake Forest University School of Medicine and associate director of the NIH supported Wake Forest Alzheimer's Disease Research Center in Winston Salem, NC, who led the study noted it is critical that people with MCI have regular supervised and supported exercise with some social component. These data support making a clinical recommendation for 120 minutes of supported exercise for adults with MCI to slow cognitive decline."

Results of the EXERT study were preseneted at the Alzheimer Association International Congress 2022 (AAIC2022) in San Diego, CA and online.