Diurnal blood pressure variation and cardiovascular prognosis in a community-based study of Ohasama, Japan.

The introduction of 24-h ambulatory blood pressure (BP) monitoring has enabled BP evaluations at specific times of the day. Associations between diurnal BP variation and cardiovascular prognosis have been investigated in the Ohasama study, which is an epidemiological survey of hypertension using ambulatory and home BP monitoring that has been ongoing since 1985 in the general population of Ohasama, a town located in northern Japan. A diminished nocturnal decline in systolic BP was associated with a greater common carotid intima-media thickness as well as a higher risk of cardiovascular morbidity and mortality, especially the risk for cerebral infarction. The consumption of large amounts of alcohol was associated with a higher morning pressor surge. A large nocturnal decline in BP and a large morning pressor surge were both associated with a risk of cerebral hemorrhage. Ambulatory BP monitoring provides not only static, but also dynamic information about BP that should be considered to ensure effective management of hypertension and cardiovascular diseases.