Sex Differences in the Relationship between Perceived Stress and Cognitive Trajectories

Area of Science:

• Neuroscience
• Immunology
• Gerontology

Background:

• Chronic stress negatively impacts cognition, partly via inflammation.
• Animal studies indicate female resilience to stress-induced cognitive dysfunction, but human data is limited.
• Understanding sex differences in stress, cognition, and inflammation is crucial for aging populations.

Purpose of the Study:

• To investigate sex differences in the relationship between perceived stress, cognitive function, and peripheral inflammation over time in cognitively normal older adults.
• To explore if older men are more susceptible to the cognitive effects of stress compared to older women.
• To examine the role of inflammatory markers, such as IL-6 and TNF-α, in mediating stress-related cognitive changes in older adults.

Main Methods:

• Longitudinal observational study involving 274 community-dwelling older adults (58% women).
• Assessed neurocognitive functioning and perceived stress (Perceived Stress Scale) over time.
• Measured plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in a subset of participants.

Main Results:

• A significant interaction between stress, sex, and time predicted executive functioning declines, with higher perceived stress linked to steeper declines in men but not women.
• In participants with inflammatory data, higher perceived stress correlated with increased IL-6 levels over time in men, but not in women.
• These findings suggest older men are more vulnerable to the cognitive aging effects of stress.

Conclusions:

• Older men exhibit greater vulnerability to the negative cognitive impacts of chronic stress, particularly in executive function.
• Systemic immunological mechanisms, indicated by increased IL-6, may contribute to the heightened risk of cognitive decline in stressed older men.
• Future research should explore personalized stress interventions to mitigate cognitive aging risks.