Magnitude of the early morning blood pressure surge in untreated hypertensive patients: a pooled analysis

OBJECTIVES: A post hoc analysis was performed to assess the magnitude of the early morning blood pressure surge (EMBPS), which is associated with peak cardiovascular risk, in untreated hypertensive patients enrolled in two sister studies (Prospective, Randomised Investigation of the Safety and efficacy of MICARDIS vs. ramipril using ambulatory blood pressure monitoring I and II) with identical design. METHODS: In adults with a mild-to-moderate primary hypertension and no significant comorbidities, 24-h ambulatory blood pressure monitoring was conducted after a 2- to 4-week placebo run-in period and before treatment initiation. Individual blood pressure measurements at 20-min intervals were analysed. RESULTS: In 1419 hypertensive patients with normal sleeping times, blood pressure displayed a typical circadian rhythm, with a mean EMBPS of 29/24 mmHg. An EMBPS of >or= 25 mmHg was observed in around 60% of patients. The surge was significantly increased with smoking, alcohol consumption, longer sleep, later waking times, and increased blood pressure variability during waking and sleeping. The magnitude of the EMBPS was significantly reduced in Black vs. White patients. The surge was not affected by gender, body mass index or duration of hypertension. Further analysis showed that ethnicity, alcohol consumption and smoking were all found to have a significant impact on surge around waking and age, sleep duration and sleep blood pressure variability were all found to have an effect on the prewake surge. CONCLUSIONS: In untreated hypertensive patients, the magnitude of the EMBPS is significant when compared with the 24-h mean and is affected by individual patient characteristics. In light of these findings, physicians should understand the importance of 24-h blood pressure control and the modification of certain lifestyle factors as ways of reducing the EMBPS.