Cardiovascular Risk Factors Impact Brain Volume and White Matter Hyperintensities: A Multiethnic Cohort Study

Brain atrophy and white matter hyperintensities (WMHs) are established markers of cerebrovascular disease, yet most evidence comes from older populations of predominantly European descent. We prospectively examined the relationship between cardiovascular risk factors and brain volumes and WMHs in middle-aged participants in a multiethnic cohort and examined ethnic differences in these associations.

Baseline data (2011-2015) were collected from 562 participants of Moroccan, South-Asian Surinamese, and Dutch descent, with 3 Tesla brain MRIs conducted between 2021 and 2022 (median follow-up 8.4 years). Brain and WMH volumes were assessed using automated segmentation of Magnetization Prepared-RApid Gradient Echo and three-dimensional Fluid-Attenuated Inversion Recovery scans. Linear regression analyses examined associations between cardiovascular risk factors and brain volumes and log-transformed WMH volumes. Interaction terms explored ethnic differences in these associations.

Median age was 53 years, and 45% were female. Higher body mass index (BMI) and diabetes mellitus were associated with lower brain volumes (-7.6 mL per BMI unit, 95% confidence interval [CI] -12.6, -2.7; 103.4 mL for diabetes, 95% CI -167.4, -39.3). Hypertension and a history of cardiovascular disease were associated with 54.7% (95% CI 25.5, 90.7) and 98.3% (95% CI 30.9, 200.4) higher WMH volumes, respectively. Associations of diabetes with brain volume and hypertension with WMH volume were most pronounced among South-Asian Surinamese participants.

Cardiovascular risk factors in midlife were strongly associated with brain volumes and WMHs after 8 years of follow-up. Ethnic differences in the strength of these associations underscore the importance of tailored cerebrovascular risk assessment across diverse populations.