Among older adults with mild cognitive impairment (MCI), an improvement in cognition is achievable when combining aerobic-resistance exercises with cognitive training compared with exercise alone, according to study findings published in JAMA Network Open.
Previous studies have demonstrated that both aerobic and strength training exercises benefit cognition in adults, as does consistent cognitive training. Other studies have proposed that vitamin D supplementation could also help preserve mental ability. However, research combining and comparing progressive physical and mental training, specifically in individuals with MCI, has shown conflicting results; and long-term benefits remain unknown. Therefore, researchers conducted the Synchronizing Exercises, Remedies in Gait and Cognition Trial (SYNERGIC; ClinicalTrials.gov Identifier: NCT02808676), spanning 5 Canadian academic research institutions, combined all 3 therapeutic modalities in a factorial design.
The researchers enrolled 175 study-eligible Canadian adults from September 2016 until April 2020. All were between ages 65 and 84 years, with a diagnosis of MCI. Prior to the 20-week study intervention, each participant was randomly assigned to 1 of 5 groups:
Group 1: Exercise, cognitive training, and vitamin D
Group 2: Exercise, cognitive training, and placebo vitamin D
Group 3: Exercise, sham cognitive training, and vitamin D
Group 4: Exercise, sham cognitive training, and placebo vitamin D
Group 5: Balance and toning exercise (nonprogressive), sham cognitive training, and placebo vitamin D
Participants and study staff assessing study outcomes were both blinded to group assignment.
Three times per week, each participant completed 60 minutes of (active or control) physical exercise and 30 minutes of (true or sham) progressive cognitive training, and also received (true or placebo) 10,000 IU vitamin D.
At baseline, 6 months, and 12 months, they completed Alzheimer Disease Assessment Scale (ADAS) Cognitive 13 and ADAS-Cognitive-Plus scales. The study’s intention-to-treat analysis used a linear mixed model with repeated measures.
At 6 months, shortly after the intervention period, pooled participants who received true exercise (Groups 1–4) had improved ADAS Cognitive 13 scores by a mean difference of 1.79 points (95% CI, −3.27 to −0.31; P =.02; Cohen’s d=0.64). Moreover, participants who completed both physical exercise and true cognitive training (Groups 1 and 2) outscored the exercise-only groups (3 and 4) by 1.45 points on the ADAS Cognitive 13 (95% CI, −2.70 to −0.21; P =.02; Cohen’s d=0.39).
During this time period, the researchers also noted that ADAS-Cognitive-Plus scores, reflecting executive function, were largely unchanged after the intervention. Cognitive scores decreased slightly in the control group (group 5).
Meanwhile, vitamin D supplementation did not add any benefit (Group 1, P =.60).
Lastly, they noted that the improvement of 2.64 points on the ADAS Cognitive 13 for group 1 alone approached the clinically significant benchmark of 3 points.
At 12 months, when physical activity had decreased, the participants had largely maintained their improved cognitive scores.
The study’s sample size and statistical power were limited by the 2020 onset of the COVID-19 pandemic. Also, the largely White, highly educated study population may limit the results’ generalizability.
Nevertheless, the researchers concluded, “Our findings suggest that this multidomain intervention could induce a clinically meaningful cognitive improvement in individuals with MCI, which may have important implications for their quality of life.”
Disclosures: Several study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see original source for full list of disclosures.
Montero-Odasso M, Zou G, Speechley M, et al. Effects of exercise alone or combined with cognitive training and vitamin D supplementation to improve cognition in adults with mild cognitive impairment: a randomized clinical trial. JAMA Netw Open. 2023;6(7):e2324465. doi:10.1001/jamanetworkopen.2023.24465