Incidence of and factors contributing to morning hypertension: Results of the Japanese Multicenter Study on Barnidipine with Ambulatory Blood Pressure Monitoring

Since ambulatory blood pressure monitoring and home blood pressure measurements came into widespread use, greater attention has been paid to high blood pressure in the morning. Morning hypertension is important not only as a trigger of cardiovascular events, which are more likely to occur in the early morning, but also as a promoting factor of cardiovascular injury. In the Japanese Multicenter Study on Barnidipine with Ambulatory Blood Pressure Monitoring (J-MUBA), the incidence of morning hypertension was investigated and classified as the surge (an increase of ≥ 30 mmHg after waking) or sustained type. Factors contributing to the development of morning hypertension were analyzed by multivariate analysis. In addition, the antihypertensive effects of the long-acting calcium channel blocker barnidipine on morning hypertension were evaluated. The incidence of morning hypertension, defined as systolic blood pressure ≥ 170 mmHg, was determined in 341 patients. Morning hypertension was observed in 126 patients (37%), among whom the surge type was seen in 36 (29%), Multivariate analysis showed that factors contributing to morning hypertension were male gender and age, after adjusting for blood pressure. In contrast, morning blood pressure was suppressed in patients with hyperlipidemia or a history of stroke. Only male gender contributed to blood pressure surge after waking. Barnidipine significantly lowered blood pressure before and after waking in patients with sustained-type morning hypertension. In patients with surge-type morning hypertension, barnidipine suppressed the abrupt increase in blood pressure after waking.