Baseline cardiovascular risk predicts subsequent changes in resting brain function

Abstract

Background and purpose: The Framingham Heart Study group cardiovascular disease risk profile (FCRP) score was used to assess the relationship between baseline cardiovascular risk and subsequent changes in resting state cerebral blood flow (CBF) in cognitively normal older participants from the Baltimore Longitudinal Study of Aging.

Methods: Ninty-seven cognitively normal participants underwent annual resting-state positron emission tomography scans at baseline and over a period of up to 8 years (mean interval, 7.4 years). Images quantifying voxel-wise longitudinal rates of CBF change were calculated and used to examine the relationship between baseline FCRP score and changes over time in regional CBF. Individual components of the FCRP score (age, cholesterol, blood pressure, smoking status, and type 2 diabetes) were also correlated with changes in regional CBF to examine the independent contributions of each component to the overall pattern of change.

Results: Higher baseline FCRP scores were associated with accelerated longitudinal decline in CBF in orbitofrontal, medial frontal/anterior cingulate, insular, precuneus, and brain stem regions. Of the components that comprise the FCRP score, higher diastolic blood pressure and diabetes were associated independently with greater decline in the medial frontal/anterior cingulate and insular regions, respectively.

Conclusions: Baseline cardiovascular risk factors are associated with greater rates of decline in resting state regional brain function. The regions showing accelerated decline participate in higher-order cognitive processes and are also vulnerable to age-related neuropathology. These results, in conjunction with other studies, encourage early treatment of cardiovascular risk factors in older individuals.

Figure 1. Baseline cardiovascular risk and subsequent changes in CBF

Higher baseline FCRP scores were associated with significant longitudinal CBF declines in the regions shown in blue. These declines in rCBF occurred over a 7.4 year period.

Figure 2. Baseline FCRP Score and Regional CBF change

The relationship between baseline cardiovascular risk score and annual rates of CBF change are shown.

Figure 3. Contributions of risk score components to rCBF change

Greater rCBF decline was associated with higher baseline diastolic blood pressure and presence of diabetes in anterior cingulate/medial frontal and insular regions, respectively (green). Regions exhibiting declining rCBF in relation to the total FCRP score from the primary analysis are also shown (blue).