Abstract INTRODUCTION The very long‐term effect of cognitive training on the risk of Alzheimer's disease and related dementias (ADRD) is unknown. METHODS This study links data from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study (a four‐arm randomized controlled trial of cognitive training in a large, diverse sample) to Medicare claims (1999 to 2019). Inclusion in the analyses required being enrolled in traditional Medicare at baseline ( n = 2021). ADRD was measured with the Chronic Conditions Warehouse algorithm. RESULTS Participants randomized to the speed‐training arm who completed one or more booster sessions had a significantly lower risk of diagnosed ADRD (hazard ratio HR: 0.75, 95% confidence interval CI: 0.59, 0.95), while speed‐trained participants with no booster training did not have a lower risk of diagnosed ADRD (HR: 1.01, 95% CI: 0.81, 1.27). There was no main effect of memory or reasoning training on risk of ADRD. CONCLUSIONS Cognitive training involving speed of cognitive processing has the potential to delay the diagnosis of ADRD. Highlights The ACTIVE study (a four‐arm randomized controlled trial of cognitive training in a large, representative sample) reports that the speed intervention arm of the study showed a reduced likelihood of being diagnosed with ADRD over a 20‐year follow‐up period. No prior cognitive training intervention has been shown to reduce risk of ADRD over a 20‐year period. Cognitive training involving speeded, dual attention, adaptive tasks has the potential to delay the diagnosis of ADRD.
Coe et al. (2026) studied this question.