Circulating cortisol and cognitive and structural brain measures in a middle-aged cohort: the Framingham Heart Study

Objective: To assess the association of early morning serum cortisol with cognitive performance and brain structural integrity in community-dwelling young and middle-aged adults without dementia.
Methods: We evaluated dementia-free Framingham Study (Generation 3) participants (mean age 48.5 years; 46.8% men), who underwent cognitive testing for memory, abstract reasoning, visual perception, attention, and executive function (n= 2231), and brain MRI (n=2018) to assess total white matter, lobar gray matter, and white matter hyperintensity volumes and fractional anisotropy (FA) measures. We used linear and logistic regression to assess the relations of cortisol (categorized in tertiles, with the middle tertile as referent) to measures of cognition, MRI volumes, presence of covert brain infarcts (CBI) and cerebral microbleeds (CMB), and voxel-based microstructural white matter integrity and gray matter density, adjusting for age, sex, APOE and vascular risk factors.
Results: Higher cortis...