Relationship between blood pressure and subcortical lesions in healthy elderly people

Abstract

Background and Purpose - The relationship between blood pressure (BP) and heart rate (HR) and MRI assessments of subcortical T2 hyperintensities was evaluated in healthy elderly men and women. Methods - Casual and 24-hour ambulatory BPs and HR measurements were taken of 144 elderly individuals, aged 55 to 79 years. Subjects had no evidence of previous health disorders. MRI scans of white matter, subcortical gray matter, and insular subcortex were coded for severity of hyperintensities. Results - Mean casual BP for the group was 120/72 mm Hg. With age and sex accounted for, individuals with the highest severity rating of white matter hyperintensities had higher casual, awake, and sleep systolic BPs; higher awake diastolic BPs; greater awake systolic BP variability; and a smaller nocturnal fall in systolic and diastolic BPs than individuals with less severe ratings. Higher severity ratings for subcortical gray matter hyperintensities were associated with elevations in casual, awake, and asleep systolic BPs and a smaller HR drop during sleep. Subjects with higher ratings for the insular subcortex had higher systolic and diastolic BPs (casual, awake, and asleep), greater HR variability during sleep, and a smaller nocturnal fall in HR. Conclusions - Casual and 24-hour ambulatory BPs and some ambulatory HR measures are associated with subcortical lesions of the brain. Longitudinal studies are needed to further explore the relationship between white matter lesions and cardiovascular measures, as well as the significance of these lesions for cerebrovascular disease in healthy elderly subjects.