# Mid-life association between cardiovascular risk factors and cerebral blood flow in a multi-ethnic population

## TL;DR

The study found ethnic differences in brain blood flow and how cardiovascular risk factors relate to these differences in midlife.

## Contribution

It reveals that associations between cardiovascular risk factors and cerebral haemodynamics emerge late in midlife and are consistent across ethnic groups.

## Key findings

- Ethnic differences in cerebral blood flow and macrovascular efficiency were observed.
- Cardiovascular disease history and high cholesterol were linked to altered cerebral haemodynamics.
- Associations between risk factors and brain blood flow appeared only in later midlife.

## Abstract

•This multi-ethnic cohort showed ethnic differences in cerebrovascular haemodynamics.•Mild associations between risk factors and cerebrovascular haemodynamics were found.•Associations appear only late in midlife, independently of ethnic risk profiles.

This multi-ethnic cohort showed ethnic differences in cerebrovascular haemodynamics.

Mild associations between risk factors and cerebrovascular haemodynamics were found.

Associations appear only late in midlife, independently of ethnic risk profiles.

Cardiovascular (CV) risk factors are associated with cerebrovascular damage and cognitive decline in late-life. However, it is unknown how different ethnic CV risk profiles relate to cerebral haemodynamics in mid-life. We aimed to investigate associations of CV risk factors with cerebral haemodynamics at two timepoints and examine the impact of ethnicity on these measures.

From the HELIUS study (53.0 years, 44.8 % female), participants of Dutch (n = 236), Moroccan (n = 122), or South-Asian Surinamese (n = 173) descent were included. Cerebral blood flow (CBF) and its spatial coefficient of variation (sCoV, an ASL-label arrival measure of macrovascular efficiency) were obtained in grey (GM) and white matter (WM). CV risk factors were assessed 8.4 years [7.4–9.5] (first visit) and 2.2 years [1.8–2.6] (second visit) prior to MRI. Associations of CV risk factors, WM hyperintensities (WMH), and carotid plaques with cerebral haemodynamics were investigated using linear regressions.

CBF and sCoV differed per ethnicity. Only at the second visit associations were found, without an interaction with ethnicity; history of CV disease with lower GM CBF and higher WM sCoV, higher total cholesterol and lower WMH volume with lower WM CBF, smoking with higher WM sCoV, and higher SBP with lower GM sCoV.

These findings suggest that cerebral haemodynamics differ between ethnic groups in midlife. Although no interaction with ethnicity was found in the associations of CV risk factors, the observed differences in CBF and sCoV highlight the need to further explore how ethnic-specific risk profiles may contribute to cerebrovascular pathology over time.

Image, graphical abstract