Lifetime hypertension as a predictor of brain structure in older adults: cohort study with a 28-year follow-up.
Allan CL., Zsoldos E., Filippini N., Sexton CE., Topiwala A., Valkanova V., Singh-Manoux A., Tabák AG., Shipley MJ., Mackay C., Ebmeier KP., Kivimäki M.
BACKGROUND:Hypertension is associated with an increased risk of dementia and depression with uncertain longitudinal associations with brain structure. AIMS:To examine lifetime blood pressure as a predictor of brain structure in old age. METHOD:A total of 190 participants (mean age 69.3 years) from the Whitehall II study were screened for hypertension six times (1985-2013). In 2012-2013, participants had a 3T-magnetic resonance imaging (MRI) brain scan. Data from the MRI were analysed using automated and visual measures of global atrophy, hippocampal atrophy and white matter hyperintensities. RESULTS:Longitudinally, higher mean arterial pressure predicted increased automated white matter hyperintensities (P<0.002). Cross-sectionally, hypertensive participants had increased automated white matter hyperintensities and visually rated deep white matter hyperintensities. There was no significant association with global or hippocampal atrophy. CONCLUSIONS:Long-term exposure to high blood pressure predicts hyperintensities, particularly in deep white matter. The greatest changes are seen in those with severe forms of hypertension, suggesting a dose-response pattern.