Lifestyle Enrichment in Later Life and Its Association With Dementia Risk.

Importance: Lifestyles enriched with socially and mentally stimulating activities in older age may help build cognitive reserve and reduce dementia risk. Objective: To investigate the association of leisure activities and social networks with dementia risk among older individuals. Design, Setting, and Participants: This longitudinal prospective cohort study used population-based data from the ASPREE Longitudinal Study of Older Persons (ALSOP) for March 1, 2010, to November 30, 2020. Community-dwelling individuals in Australia aged 70 years or older who were generally healthy and without major cognitive impairment at enrollment were recruited to the ALSOP study between March 1, 2010, and December 31, 2014. Data were analyzed from December 1, 2022, to March 31, 2023. Exposures: A total of 19 measures of leisure activities and social networks assessed at baseline were classified using exploratory factor analysis. Main Outcomes and Measures: Dementia was adjudicated by an international expert panel according to Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) criteria. Cox proportional hazards regression examined dementia risk over 10 years, adjusting for education, socioeconomic status, and a range of health-related factors. Results: This study included 10 318 participants. Their median age was 73.8 (IQR, 71.6-77.2) years at baseline, more than half (52.6%) were women, and most self-identified as White (98.0%). In adusted analyses, more frequent engagement in adult literacy activities (eg, writing letters or journaling, using a computer, and taking education classes) and in active mental activities (eg, playing games, cards, or chess and doing crosswords or puzzles) was associated with an 11.0% (adjusted hazard ratio [AHR], 0.89 [95% CI, 0.85-0.93]) and a 9.0% (AHR, 0.91 [95% CI, 0.87-0.95]) lower risk of dementia, respectively. To a lesser extent, engagement in creative artistic activities (craftwork, woodwork, or metalwork and painting or drawing) (AHR, 0.93 [95% CI, 0.88-0.99]) and in passive mental activities (reading books, newspapers, or magazines; watching television; and listening to music or the radio) (AHR, 0.93 [95% CI, 0.86-0.99]) was also associated with reduced dementia risk. In contrast, interpersonal networks, social activities, and external outings were not associated with dementia risk in this sample. Conclusions and Relevance: These results suggest that engagement in adult literacy, creative art, and active and passive mental activities may help reduce dementia risk in late life. In addition, these findings may guide policies for geriatric care and interventions targeting dementia prevention for older adults.