Association of Dementia and Vascular Risk Scores With Cortical Thickness and Cognition in Low-risk Middle-aged Adults.

BACKGROUND: Increased risk for the future development of Alzheimer disease begins as early as midlife. Algorithm-based scores, such as the Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE) dementia risk score, and the Framingham general cardiovascular disease (CVD) risk score, have been used to determine future risk for the development of cognitive decline and dementia. We evaluated the association between neuroimaging and cognitive measures with the 2 risk scores in middle-aged, cognitively intact adults (49±6 y). METHODS: In a cohort of 132 participants collected in 2014, magnetic resonance imaging was used to determine measures of cortical thickness in a priori regions of interest and a neuropsychological battery to assess memory and executive function. RESULTS: The CAIDE dementia risk score was significantly and inversely associated with the cortical thickness of the parahippocampal (r=-0.266; P=0.002) and superior frontal gyrus (r=-0.261; P=0.002) despite a considerable percentage of individuals (99.3%) at low risk for CVD. There was a significant negative association between CAIDE and memory (r=-0.251; P=0.003). Framingham general CVD score was not associated with brain structure or cognitive function. CONCLUSIONS: These results indicate that the CAIDE dementia risk score is associated with cortical thickness and cognitive function at midlife in a low-risk population. These data provide insight into subclinical structural and functional changes occurring during midlife associated with future risk for the development of dementia.