Morning blood pressure surge is associated with death in hypertensive patients

Morning blood pressure surge (MS), defined as the difference between the mean blood pressure (BP) 2 h after waking up and the mean of the three lowest BP values during sleep, has been correlated with increased cardiovascular risk. We sought to evaluate its association with cardiovascular events and death.

We retrospectively analyzed data from 632 hypertensive patients [median age 58 years (50-67 years), 37% men] who underwent ambulatory BP monitoring between January 2005 and December 2006. Patients were divided into two groups according to MS (≥41 mmHg and <41 mmHg), and mortality from any cause was retrieved after a median time of 50 months (46-54 months).

Patients with MS of 41 mmHg or higher were older, had a higher daytime systolic BP, as well as a higher systolic and diastolic dipping, and a lower night-time diastolic BP. During follow-up, there were 19 deaths and MS of 41 mmHg or higher was associated with a higher hazard for death in the crude model [hazard ratio: 3.47 (95% confidence interval: 1.25-9.65)], as well as after adjustments for age and the presence of diabetes [hazard ratio: 3.35 (95% confidence interval: 1.18-9.49)].

An increased BP surge is associated with higher hazard for death. Future studies specifically designed to evaluate the real impact of MS on outcomes, as well as to define its optimal cutoff value, are required.