Psychological Stress across the Lifespan and Cognitive Function among Older Adults: The Moderating Role of a Healthy Lifestyle

This study aimed to (a) investigate the associations between indices of stress severity across the lifespan (early, middle, late life) and cognitive function among community-dwelling older adults, and (b) examine whether a healthy lifestyle composite score comprised of physical activity, healthy diet adherence, social engagement, sleep quality, and mindful relaxation moderates the associations between lifespan stress severity and cognitive function. Participants (n = 226, M_age = 68.2 ± 6.5, 68.1% female) completed questionnaires to measure stress and lifestyle behaviours, and three online neurocognitive tasks. No direct associations between stress severity and cognition were found. The healthy lifestyle composite score moderated the associations between early, midlife, and late-life stress severity and inhibitory control. Exploratory analyses suggest that this moderating effect may be sex-dependent. Despite study limitations and the need for additional research, findings provide preliminary support for the role of lifestyle behaviours in enhancing older adults’ resilience to the effects of stress on cognitive health in a sex-specific manner.

Plain Language Summary

Psychological stress is a risk factor for poor cognitive health during aging. But it is unknown how stress at different life periods is associated with cognitive function. Also, some things might minimize the effects of stress on cognitive function. A healthy lifestyle is associated with better cognitive function and reduced feelings of stress. Therefore, the goal of the current study was to examine how stress across the lifespan (early life, midlife, later life, and total lifetime stress) is associated with cognitive function among older adults. We also examined whether a healthy lifestyle minimizes the link between psychological distress and cognitive function. The study participants were 226 older adults. They answered questions online about stress across the lifespan and lifestyle behaviours. They also completed a set of online cognitive tasks. The study results showed that stress across the lifespan was not directly associated with cognitive function. However, higher stress in early life was associated with poorer cognitive function among those who did not engage in as much of a healthy lifestyle. On the other hand, higher stress in midlife and later life was associated with better cognitive function among those who reported high engagement in a healthy lifestyle. This means that that early life stress is potentially harmful for cognitive function, but it may be minimized through healthy lifestyle behaviours. The findings also suggest that engaging in a healthy lifestyle can make older adults more resilient to the effects of stress in midlife and later life on cognitive function. Importantly, this study also emphasizes the value of studying sex difference in cognitive aging research.