Effectiveness of cognitive interventions in healthy aging: A systematic review and Bayesian meta-analysis

The global increase of the aging population poses major public health challenges, particularly due to the rising prevalence of age-related diseases. Among these, dementia stands out as a condition with the most significant health, social, and economic impact. Primary prevention in healthy aging, thus far, represents the most effective strategy to address this issue, and cognitive interventions emerge as promising tools to enhance and preserve cognitive functions over time. This study aimed to provide a systematic review and meta-analysis of cognitive interventions in healthy older adults, assessing their effectiveness both on cognitive performance (i.e., global cognitive functioning and main cognitive domains), measured by neuropsychological tests, and psychological components (e.g., psychiatric symptoms, quality of life, reported cognitive complaints). The use of a multilevel Bayesian approach allowed us to enhance the reliability of our findings by accounting for data structure and variability across studies. A total of 51 studies were included in the systematic review, and 43 in the meta-analysis. The results indicated that, compared to control groups, cognitive interventions are more effective in improving overall cognition (0.26; 95 % CI [0.08, 0.44]). Evidence of effectiveness, albeit with smaller effect sizes, was also observed on specific cognitive domains. No effects emerged for psychological outcomes. Our findings underscore the relevance of cognitive interventions as an effective tool to promote cognitive health and prevent cognitive decline in the aging population. More research will be necessary to explore further the effectiveness of cognitive intervention on psychological components.