Blunted nocturnal fall in blood pressure in hypertensive women with future cardiovascular morbid events

Abstract

Background: In essential hypertension, a blunted or absent nocturnal fall in blood pressure (BP) may be associated with increased target organ damage. In this case-control study, we tested the hypothesis that an association exists between a blunted or absent nocturnal fall in BP and future cardiovascular morbid events in patients with essential hypertension.

Methods and results: Case subjects were 32 hypertensive patients with a first fatal or nonfatal major cardiovascular event who had off-therapy ambulatory BP monitoring 1 to 5 years earlier in the context of a registry of morbidity and mortality in hypertensive patients. Control subjects were 49 hypertensive patients free from cardiovascular events. The groups were matched with regard to date of baseline ambulatory BP monitoring, age, sex, clinic systolic and diastolic BP, and daytime ambulatory systolic and diastolic BP. At their baseline evaluation, cases and controls did not differ, in either sex, with respect to clinic BP (men, 164/100 vs 162/99 mmHg; women, 178/96 vs 180/93 mmHg), mean daytime ambulatory BP (men, 151/94 vs 147/95 mm Hg; women, 156/90 vs 158/89 mm Hg), age (men, 55 vs 56 years; women, 69 vs 68 years), sex, body weight, serum cholesterol, known duration and family history of hypertension, smoking habits, renal function, or prevalence of diabetes. Echocardiographic left ventricular mass, determined in a subset of patients, was greater in cases than in controls in men (145 vs 115 g/m2, P = .038) and women (137 vs 102 g/m2, P = .032). The time interval between baseline ambulatory BP monitoring and subsequent cardiovascular event (cases: mean, 2.1 years) or last contact with our center (controls: mean, 2.5 years) did not differ between the groups. In the baseline ambulatory BP profile, the nocturnal reductions of systolic and diastolic BP in men were 9% and 11%, respectively, in cases vs 9% and 12% in controls (all P = NS), whereas in women they were 3% and 8% in cases vs 11% and 16% in controls (P = .002/.004).

Conclusions: This retrospective case-control study suggests an association between the reduction or absence of the usual nocturnal fall in BP and future cardiovascular morbid events in white women with essential hypertension.