Diminished Nocturnal Blood Pressure Decline and Lesion Site in Cerebrovascular Disease

Abstract

Background and Purpose Many studies have suggested that diminished nocturnal blood pressure decline in hypertensive cardiovascular disease is associated with the extent of hypertensive vascular disease. In our previous observation of cerebrovascular disease, however, we found reduced nocturnal blood pressure decline to be associated not only with the extent of hypertensive vascular disease but also with the specific location of cerebrovascular lesions. The purpose of this study was to elucidate the mechanism of nocturnal blood pressure decline in cerebrovascular disease. Moreover, to clarify whether reduced nocturnal blood pressure decline occurs before cerebrovascular disease, we examined patients with recurring episodes. Methods Ambulatory blood pressure monitoring was carried out every 30 minutes in 14 control subjects, 15 hypertensive subjects, 90 patients with cerebrovascular disease (16 single lacunar infarctions, 15 multiple lacunar infarctions, 10 putaminal hemorrhages, 14 thalamic hemorrhages, 11 pontine base infarctions, 15 pontine tegmentum infarctions, 8 pontine hemorrhages, 13 wide cortical infarctions), and 7 patients with recurring stroke episodes. The percentage of nocturnal blood pressure decline and the correlations for systolic blood pressure and heart rate were calculated. Results The percentage of nocturnal blood pressure decline was significantly smaller in the groups with multiple lacunar infarction (systolic, P <.001; diastolic, P <.01), thalamic hemorrhage ( P <.01, P <.05), pontine tegmentum infarction ( P <.01, P <.05), and pontine hemorrhage (both P <.05). The correlation between systolic blood pressure and heart rate was not significant for almost all the groups with diminished blood pressure decline. Conclusions Diminished nocturnal blood pressure decline in cerebrovascular disease is thought to be caused by specific injury to the central autonomic nervous system such as the striatum, diencephalon, midbrain, and pontine tegmentum and their connecting fibers.