Sex-specific Relationship of Cardiometabolic Syndrome with Lower Cortical Thickness

Objective: To investigate whether cardiometabolic factors were associated with age-related differences in cortical thickness in relation to sex.

Methods: In this cross-sectional study, we enrolled 1,322 cognitively normal elderly (≥65 years old) individuals (774 [58.5%] men, 548 [41.5%] women). We measured cortical thickness using a surface-based analysis. We analyzed the associations of cardiometabolic risk factors with cortical thickness using multivariate linear regression models after adjusting for possible confounders and interactions with age.

Result: Among women, hypertension (β = -1.119 to -0.024, < 0.05) and diabetes mellitus (β = -0.920, = 0.03) were independently associated with lower mean cortical thickness. In addition, there was an interaction effect between obesity (body mass index [BMI] ≥27.5 kg/m) and age on cortical thickness in women (β = -0.324 to -0.010, < 0.05), suggesting that age-related differences in cortical thickness were more prominent in obese women compared to women with normal weight. Moreover, low education level (<6 years) was correlated with lower mean cortical thickness (β = -0.053 to -0.046, < 0.05). Conversely, among men, only being underweight (BMI ≤18.5 kg/m, β = -2.656 to -0.073, < 0.05) was associated with lower cortical thickness.

Conclusions: Our findings suggest that cortical thickness is more vulnerable to cardiometabolic risk factors in women than in men. Therefore, sex-specific prevention strategies may be needed to protect against accelerated brain aging.