Changes of circadian blood pressure patterns are associated with the occurrence of lacunar infarction

Background: The occurrence of lacunar infarction is closely related to arterial hypertension. However, there is only limited and partly controversial knowledge regarding the possible pathogenetic role of circadian blood pressure changes. Objective: To evaluate the relationship between circadian blood pressure rhythm, occurrence, and extent of lacunar infarction. Methods: We analyzed circadian blood pressure patterns, other cardiovascular risk factors, and occurrence of lacunar infarction in 118 hospitalized patients older than 55 years. Noninvasive 24-hour blood pressure measurements and magnetic resonance or computed tomographic brain imaging were performed in 61 patients with lacunar infarction and in 57 control patients. Daytime blood pressure variability was defined as the within-subject SD of all systolic and diastolic blood pressure readings during the daytime measurement period. Circadian blood pressure variation was defined as the average percentage change of nighttime blood pressure values compared with the daytime blood pressure values. Results: Patients with lacunar infarction were significantly older and showed more often a history of arterial hypertension, elevated average daytime blood pressure values, an increased systolic daytime blood pressure variability, and a reduced circadian blood pressure variation due to an increased incidence of a pathologic nighttime blood pressure increase. No significant correlation was found between these parameters and the number of lacunae. A logistic regression analysis revealed that a reduced systolic circadian blood pressure variation, age, systolic average daytime blood pressure, and a history of arterial hypertension were best correlated with the occurrence of lacunar infarction. Conclusion: Reduced nighttime decline in systolic blood pressure may be an important risk factor for the development of lacunar infarction in addition to the absolute level of blood pressure and age.