Association of Blood Pressure, White Matter Lesions, and Regional Cerebral Blood Flow

BACKGROUND At present, the association between blood pressure, regional cerebral blood flow, and white matter lesions is not well understood. MATERIAL AND METHODS A total of 147 subjects aged from 40 to 80 years were assessed by the Fazekas score for white matter lesions, CT perfusion imaging for regional cerebral blood flow, and 24-h ambulatory blood pressure monitoring for blood pressure level and rhythm. Logistic regression analysis was used to obtain the odds ratio and 95% confidence interval between Fazekas scores and relevant factors. The relationship between blood pressure index and regional cerebral blood flow was analyzed through cubic curve estimation. RESULTS Fazekas score was negatively correlated with regional cerebral blood flow (r=-0.801; r=-0.831, P<0.001). For subcortical lesion, the regional cerebral blood flow of Fazekas grade 0 was 1.976 times that of Fazekas grade 3 (OR=1.976, 95% CI=1.576-2.477), and for periventricular lesion, the regional cerebral blood flow of Fazekas grade 0 was 2.034 times that of Fazekas grade 3 (OR=2.034, 95% CI=1.602-2.583). Increased nighttime systolic blood pressure may be more dangerous (OR=1.112, 95% CI=1.059-1.169). The day-night systolic blood pressure ratio (OR=0.801, 95% CI 0.711-0.902) and the day-night diastolic blood pressure ratio (OR=0.876, 95% CI 0.807-0.950) were significantly correlated with Fazekas score. CONCLUSIONS The decrease of white matter regional cerebral blood flow caused by hypertension is probably one of the important causes of white matter lesions. Patients with white matter lesions should also pay attention to the rhythm of blood pressure when controlling hypertension, especially if their blood pressure is too high or too low at night.