One simple, no-cost change appears to lower cardiovascular (CV) risk among patients with resistant hypertension. By taking their antihypertensive medications at bedtime instead of in the morning, patients in a Spanish trial significantly reduced their cardiovascular risk.
Researchers have known that sleep-time blood pressure (BP) better predicts CV risk than does either the awake or 24-hour BP means. However, all previous studies relied on a single baseline ambulatory blood pressure monitoring (ABPM) profile on each participant at the beginning of the study. Thus, they could not detect changes in the pattern or level of BP if they occurred.
Reporting at the 48th Congress of the European Renal Association—European Dialysis and Transplant Association in Prague, lead investigator Ramón Hermida, PhD, director of the laboratory of bioengineering and chronobiology at the University of Vigo in Vigo, Spain, told ASN Kidney News that his study tested the hypothesis that bedtime dosing of at least one blood pressure medication would more effectively reduce CV disease (CVD) risk than would conventional morning dosing of all of a patient’s antihypertensive medications. He pointed out that bedtime dosing is a cost-effective and simple strategy to achieve adequate asleep BP reductions and to re-establish a normal 24-hour pattern of BP reduction at night (“dipping pattern”) if it is missing.
Hermida reported the results of a substudy of a larger study of people with hypertension, which was prospective, randomized, and open-label. In the substudy, 776 participants with resistant hypertension had a mean age of 61.6 years, an approximately equal number of men and women, and were randomly assigned to take all their prescribed BP medications upon awakening or at least one of them at bedtime. At the physician’s discretion, additional antihypertensive medication could be added as required, but no nighttime medication was allowed in the morning, meaning that any one drug could not be taken at both times. For controls, who took all BP medication in the morning, any additional BP medications also had to be taken in the morning.
At baseline, BP was measured at 20 min intervals during waking hours and at 30 min intervals at night. A wrist actigraph recorded periods of daytime activity and noctural sleep. These measurements were performed annually, or quarterly if treatment adjustments were necessary. Patients were followed for a median of 5.4 years.