A 4-month, moderate- to high-intensity aerobic and strength exercise training program did not delay cognitive decline in older adults with mild to moderate dementia, findings reported in a BMJ study showed.
“The results of recent systematic reviews of trials of exercise training in people with dementia have conflicted,” Sarah E. Lamb, MSc, MCSP, DPhil, from University of Oxford, and the Warwick Clinical Trials Unit at University of Warwick, England, and colleagues wrote. “The hypothesis that aerobic and strengthening exercise might slow cognitive impairment in dementia has gained widespread popularity.”
In this multicenter, randomized controlled trial in England, known as the Dementia and Physical Activity trial, researchers examined whether exercise benefited cognitive impairment in people with dementia. Lamb and colleagues randomly allocated 329 older adults with dementia to an aerobic and strength exercise program and 165 to receive usual care.
Patients received either usual care plus 4 months of 60- to 90-minute sessions of supervised exercise and support for ongoing physical activity twice a week, or usual care only. The investigators measured physical fitness in the exercise arm during the intervention and examined scores on the Alzheimer’s disease assessment scale-cognitive subscale at 12 months. They also assessed activities of daily living, neuropsychiatric symptoms, health-related quality of life and caregiver quality of life and burden.
Moderate- to high-intensity exercise did not delay cognitive decline in older adults with mild to moderate dementia, study findings showed.
Cognitive impairment declined over the 12-month follow-up in both trial arms, with the exercise arm showing slightly higher global Alzheimer’s disease assessment scale-cognitive scores (adjusted mean difference 1.4; 95% CI, 2.6 to 0.2). However, the clinical relevance of this difference is uncertain, according to the authors. The investigators found that 65% of participants with dementia assigned to the exercise program attended more than 75% of scheduled sessions and that participants’ 6-minute walking distance improved over 6 weeks (mean change = 18.1 m; 95% CI, 11.6-24.6).
Analysis showed no differences between the groups in activities of daily living, neuropsychiatric symptoms, health related quality of life and caregiver quality of life and burden or subgroup analyses by dementia type, severity of cognitive impairment, sex and mobility. The complier average causal effect estimates for score on the Alzheimer’s disease cognitive scale at 12 months was 2, which indicated worse cognitive impairment in people who attended more sessions (95% CI, 3.87 to 0.22).
“Moderate- to high-intensity aerobic and strength exercise cannot be recommended as a treatment option for cognitive impairment in dementia. ... Although moderate- to high-intensity exercise improves physical fitness, no clinical outcomes that we studied responded in a positive direction,” Lamb and colleagues wrote. “Future trials should explore other forms of exercise, including psychomotor protocols that are commonly used in long-term neurological conditions where the primary intent is improving physical functioning.” – by Savannah Demko
Disclosures: The authors report no relevant financial disclosures.