Nocturnal blood pressure as a predictor for total and cardiovascular mortality in hypertensive patients with various clinical problems. A prospective 10 year observational data

Abstract

Background: Nocturnal blood pressure has been known to be a prognostic marker for hypertensive patients in general population and subclinical organ damage. But it is not clear if nocturnal blood pressure is also valuable in more complicated clinical situation for hypertensive patients. Method: Ambulatory blood pressure monitoring(ABPM) data from all patients who underwent between 1994 and 1996 were followed for their vital status until 2006. Among 458 patients, 265(51.8%) were complicated by heterogeneous clinical problems. Nondipper was defined by 8% or less decline of nocturnal systolic blood pressure using fixed time interval methods in which sleep time was between 10PM and 7AM. Odds ratio was adjusted with age and gender. Results: The age was 54.4 14.5 and 46.5% were male patients. Profile of the clinical problems were diabetes(27), heart diseases(35), cerebrovascular diseases(57), tumor(43), infection(28), trauma(21) pregnancy(4), and others(24). 286(62.8%) patients were nondipper. Among 99(21.5%) total deaths, cardiovascular deaths were 38(8.3%). All cause mortality was higher in nondipper (14.5% in dipper vs 25.8% in nondipper, p=0.004). Odds ratio of cardiovascular deaths including stroke and cardiac death was 1.13(CI:1.08-1.17) for age, 2.14(CI:0.99-4.65) for gender and 2.77(1.09-6.98) for nondipper(p for nondipper, 0.011). Cardiac deaths occurred in 16(3.48%) patients and they were not different between dipper(1.74%, 3/169) vs nondipper(4.55%, 13/273) (p=0.113). Conclusion: Nocturnal blood pressure during ABPM can predict total mortality and cardiovascular mortality in a real clinical situation for hypertension which may be complicated by heterogeneous clinical problems.