Determinants of white matter hyperintensity volume in patients with acute ischemic stroke.

BACKGROUND: White matter hyperintensity (WMH) is a common radiographic finding in the aging population and a potent risk factor for symptomatic cerebrovascular disease. It is unclear whether WMH represents a single or multiple biological processes. We sought to investigate the extent and determinants of WMH in patients with acute ischemic stroke (AIS).

METHODS: We retrospectively analyzed a prospectively enrolled hospital-based cohort of patients with AIS. WMH volume (WMHV) was measured using a previously published method with high interrater reliability based on a semiautomated image analysis program.

RESULTS: WMHV was measured in 523 consecutive patients with stroke (mean age 65.2 years, median WMHV 8.2 cm(3)). In univariate linear regression analyses, individuals who were older, had elevated homocysteine (HCY) level or systolic blood pressure, or history of hypertension (all P < .0001), decreased glomerular filtration rate (P < .0002), atrial fibrillation (P < .0008), or coronary artery disease (P < .03) had significantly greater WMHV. After multivariable adjustment, only age (P < .0001) and HCY levels greater than 9 mumol/L (P < .003) remained independently associated with WMHV.

CONCLUSIONS: In patients with AIS, risk factors for WMH severity do not appear to overlap with those previously reported for population-based cohorts. Only age and higher HCY levels were independently associated with more severe WMH in patients with stroke. This suggests that some of the processes underlying WMH burden accumulation in patients with stroke may differ from those in the general population and are not simply mediated by traditional vascular risk factors.