Cerebral vasomotor reactivity and extent of white matter lesions in middle-aged men with arterial hypertension: a pilot study.

Background: Cerebrovascular reactivity (CVR) impairment and cerebral white matter lesions (WMLs) are associated in elderly or patients with overt cerebral ischemia. Such association has not been confirmed for asymptomatic middle-aged individuals with risk factors for stroke. We assessed the relationship between the CVR and the presence of WMLs in a middle-aged population-based cohort of hypertensive men.
Methods: Magnetic resonance imaging (MRI) and transcranial Doppler (TCD) examination were performed in 54 hypertensive men, all at 60 years of age, without a history of stroke, neurologic deficits, or carotid stenosis. The CVR of the middle cerebral artery (MCA) was expressed as the vasomotor reactivity reserve (VMRr).
Results: WMLs were detected in 22 men (40.7%); all WMLs were classified as mild (first grade of the Fazekas modified scale). The VMRr was lower in patients with WMLs (mean 55%; s.e. 3%) compared to those without WMLs (mean 65%; s.e. 3%; P = 0.03). The lower VMRr in patients with WMLs was consistent after controlling for confounders. A higher pulsatility index (PI) in subjects with WMLs (mean 1.08; s.e. 0.05) compared to those without WMLs (mean 0.90; s.e. 0.05; P = 0.01) was not consistent after controlling for confounders.
Conclusions: The CVR was lower in middle-aged hypertensive men with WMLs compared to those without WMLs indicating that even a low load of WMLs may reflect some functional impairment of the cerebral microvasculature.