Abstract
Up to 40% of dementias may be preventable via risk factor modification. This inference has motivated the development of lifestyle interventions for reducing cognitive decline. Typically delivered to older adults face-to-face, the COVID-19 pandemic has necessitated their adaptation for remote delivery. We systematically reviewed randomized controlled trials of remotely delivered lifestyle interventions (≥4 weeks duration and delivered >50% remotely), for adults aged ≥ 60 without dementia, examining effects on objective cognitive measures. Comparators were active (face-to-face or remote) or passive. Ten studies (n = 2967) comprising multidomain (k = 4), physical activity (k = 3) or psychosocial (k = 3) remote interventions were included. Data were synthesized using robust variance estimation meta-analysis. The pooled estimate comparing the effect of remote interventions versus comparators on cognition was not significant (g=-0.02; 95%CI [-0.14, 0.09]; p = .66); subgroup analyses by type of intervention or comparator also yielded non-significant effects. Most studies had low risk of bias. Current evidence to support remote lifestyle interventions is limited. Included studies were conducted pre-pandemic, and evaluated individual, rather than group interventions. Future studies may exploit the greater digital connectivity of older people since the pandemic. Group formats, more frequently efficacious than individual interventions in face-to-face dementia prevention trials, may be a rational approach for future remote trials.