Ambulatory blood pressure and the brain: a 5-year follow-up

To determine if initial values of casual and ambulatory systolic blood pressure (SBP) predict white matter hyperintensities, insular subcortex hyperintensities, and brain atrophy 5 years later in a group of healthy elderly individuals.

The authors studied 155 healthy men and women, aged 55 to 79 years. Two 24-hour ambulatory blood pressure (BP) sessions assessed BP level and variability during waking and sleep. Hyperintensities and total brain volume were quantified by MRI. Procedures were repeated 5 years later in 78% (121) of subjects.

Hyperintensities and brain atrophy increased over time, with greater increases among older subjects. The presence of increased BP level and variability initially and again 5 years later had negative consequences for the brain. Independent of age, the greater the initial SBP, the greater the likelihood that individuals would have severe white matter hyperintensities after 5 years. Also, elevated casual SBP was associated with severe insular subcortex hyperintensities and greater SBP sleep variability with increased brain atrophy.

Among healthy elderly individuals whose initial, average, casual blood pressure (BP) was relatively low (116.9/71.1 mm Hg), small increases in casual and 24-hour ambulatory BP measures were associated with greater brain atrophy and subcortical lesions after 5 years.