Can brain training prevent dementia? Long-term testing shows that speed training with boosters makes a difference

A 20-year landmark analysis of the ACTIVE trial suggests that targeted, speed-based enhanced cognitive training can delay the diagnosis of dementia, offering new insight into how structured mental exercises could support long-term brain health in aging populations.

Study: Effect of cognitive training on claims-diagnosed dementia over 20 years: evidence from the ACTIVE study. Image credit: Oksana Tkachova / Shutterstock

In a recent study published in the journal Alzheimer’s & Dementia: Translational Research & Clinical Interventionsa team of researchers determined whether domain-specific cognitive training reduces the long-term risk of Alzheimer’s disease and related dementia (ADRD) over 20 years using Medicare claims data.

Background and Rationale

Nearly half of Americans over the age of 85 are expected to develop dementia in their lifetime, but a question arises: can we train the brain to resist decline? Cognitive training programs promise sharper memory and faster thinking, but debate continues as to whether such improvements translate into actual protection against ADRD. Improvements in thinking, memory and processing speed are well documented in the short term, but long-term prevention of dementia remains uncertain. Studying how mental exercises affect clinical diagnoses of dementia has important implications for changing government policy related to aging, care, and health care costs. Therefore, more research is needed to identify the types of exercises that offer a long-term basis of protection.

Study Design and Methods

The Advanced Cognitive Training for Independent and Vital Elderly study was a four-arm, multisite, single-blind randomized controlled trial involving 2,802 community-dwelling adults aged 65 years and older between 1998 and 1999. Four groups were created: participants received memory training, reasoning training, and no control group training. considering.

To be eligible, participants must have scored 23 or higher on the Mini-Mental State Examination and have independence in all activities of daily living. Individuals who had a recent stroke in the previous 12 months, were undergoing cancer treatment (chemotherapy or radiation), or had any sensory impairments that would prevent participation in the study were excluded from the sample population.

In this analysis, participant data were linked to Medicare claims from January 1, 1999 to December 31, 2019. The final analytic sample included 2,021 people enrolled in traditional Medicare at baseline. ADRD was identified using the Chronic Repository Conditions algorithm based on International Classification of Diseases codes. Cause-specific Cox proportional hazards models for risk of dementia diagnosis, with hazard ratios adjusted for competing risks of death, were estimated and adjusted for age, sex, race, education, marital status, cardiovascular comorbidities, smoking status, and baseline cognitive scores, with additional adjustment for study site and education. Reminder training sessions (offered at 11 months and 35 months) were analyzed separately among participants who completed at least 8 of the initial 10 training sessions and were therefore eligible for reminder randomization.

Results of long-term dementia risk

Over 20 years of follow-up, 48.7% of control group participants received a diagnosis of ADRD. The death rate was high in all groups, with 77% dying during follow-up, reflecting the advanced age of the cohort. Baseline demographic and health characteristics were balanced across intervention arms.

When looking at the first round of assessments only, none of the three training arms showed a statistically significant reduction in dementia risk compared with the control group, after adjusting for covariates. There was some evidence of a small reduction in risk, about 12–15% lower as the hazard ratio suggests, but again, none were statistically significant.

The most notable finding emerged when recall sessions were examined. Participants assigned to processing speed training who were randomized to receive reinforcement training had a statistically significant 25% lower risk of diagnosed ADRD compared with the control group (adjusted hazard ratio 0.75, 95% confidence interval 0.59 to 0.95). In contrast, speed-trained participants who did not receive reminder sessions showed no protective benefit (hazard ratio 1.01, 95% confidence interval 0.81 to 1.27).

In the speed training arm, participants who received memory training had a lower, borderline statistically significant risk compared with those who were eligible for boosters but not assigned to boosters (hazard ratio 0.81, 95% confidence interval 0.66 to 1.00). Therefore, the results of this study suggest that booster sessions may enhance or maintain training effects, although these findings should not be interpreted as definitively causal, given that booster eligibility requires completion of the session after randomization and may introduce selection bias. It was also observed that training focused on memory or reasoning skills did not reduce the risk of dementia, regardless of reminiscence participation.

Age did not significantly alter training outcomes, but younger participants in the memory arm showed a trend toward lower risk of dementia, and this association was not statistically significant. Competing Fine-Gray risk models produced similar results.

Real World Implications

From a real-world perspective, these findings make sense. Processing speed training emphasized visual attention and rapid information processing, particularly divided attention, skills closely related to everyday tasks such as driving. Previous analyzes of the same cohort showed reduced at-fault motor vehicle crashes among speed-trained participants, reinforcing the practical value of this intervention. The current results suggest that sustained, adaptive training targeting attention and processing speed may not only improve daily functioning but also be associated with delayed clinical diagnosis of dementia, although the study was based on claims-based diagnoses rather than validated clinical assessments and may underestimate or misclassify actual cases of dementia depending on health care utilization and diagnostic coding practice.

conclusions

Over two decades of follow-up, cognitive training focused on processing speed, particularly when enhanced with reminiscence sessions, was associated with a significantly reduced risk of ADHD. Memory and reasoning training did not show comparable long-term protection. These findings suggest that attention-based adaptive cognitive exercises may help delay the diagnosis of dementia in older adults. Although not a cure, such interventions could extend years of independence and reduce societal burden. However, because the outcome was based on Medicare claims and the analytic sample excluded individuals enrolled in Medicare Advantage at baseline, generalizability may be limited and further confirmation using clinically assessed outcomes is required.