Brainstem white matter hyperintensities may predict first-ever stroke
Background: No prior research has determined whether brainstem white matter hyperintensities (b-WMHs) are associated with first-ever stroke. This study aims to investigate whether b-WMHs can predict first-ever stroke. Methods: This was a retrospective study. Clinical records and magnetic resonance imaging (MRI) scans reviewed to identify patients with and without brainstem white matter hyperintensities (b-WMHs). A total of 180 individuals with b-WMHs and no prior history of stroke, and 205 individuals without b-WMHs, were included. Stroke incidence within a three‑year observation window was determined retrospectively from medical records and confirmed by neuroimaging, following American Heart Association/American Stroke Association (AHA/ASA) guidelines. Predictors of stroke were evaluated using Cox regression analysis. Results: Within the three‑year observation window, 37 patients (9.6%) experienced a first‑ever stroke, 40.5% in the anterior circulation and 59.5% in the posterior circulation. Stroke incidence was significantly higher among patients with b‑WMHs (13%) compared with those without (6%) (OR, 2.27; 95% CI, 1.12–4.61; P=0.02). In multivariable Cox regression analysis, stroke occurrence was independently associated with hypertension (HR, 5.39; P<0.001), diabetes mellitus (HR, 4.39; P=0.007), hyperhomocysteinemia (HR, 2.66; P=0.004), and atrial fibrillation (HR, 3.00; P<0.01). The association between b‑WMHs and stroke remained significant after adjustment for age, sex, and supratentorial WMHs (s‑WMHs), but lost statistical significance when additional vascular risk factors were included. Conclusion: Brainstem white matter hyperintensities are associated with first-ever stroke but are not independent risk factors. Further studies are needed to explore the mechanisms linking b-WMHs to stroke risk.