A retrospective analysis of serious adverse events and deaths in U.S.-based lifestyle clinical trials for cognitive health.

Objective:This retrospective analysis examined serious adverse events (SAEs) and deaths in U.S. lifestyle clinical trials aimed at enhancing cognitive health in older adults. Methods:Data was gathered from trials completed between January 1, 2000, and July 19, 2023, via ClinicalTrials.gov's API. Results:Among these trials, 76% did not report results. The remaining studies fell into four intervention categories: Cognitive/Behavioral, Exercise/Movement, Diet/Supplement, and Multi-modal. When considering all trial types collectively, the findings suggest that lifestyle clinical trials are generally safe. There was no significant increase in the relative risk of experiencing an SAE in the intervention group compared to the control group. However, in terms of relative risk of death, an increase of 28% was observed in the intervention compared to the control, which was statistically significant (X2 (1, N = 36), p < 0.00688). Nevertheless, this increase did not surpass age-adjusted U.S. mortality rates. Assessing the data by intervention type, Diet/Supplement, and Multi-modal trials displayed an elevated relative risk of SAEs in the intervention. Diet/Supplement trials had a 16% increase (X2 (1, N = 2), p < 0.0263), and Multi-modal trials had a 365% increase (X2 (1, N = 5), p < 0.000213). Diet/Supplement trials also showed a 67% increased risk of death (X2 (1, N = 2), p < 0.000197). Conclusions:These findings should be cautiously considered due to the low rate of reporting, but underscore the significance of reporting clinical trial results, enhancing transparency, and facilitating more accurate safety assessments in cognitive aging and lifestyle interventions for older adults.