BP meds: This simple change improves outcomes

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For patients with uncontrolled hypertension, a switch to bedtime dosing is advisable.




Advise patients with uncontrolled hypertension to take at least one of their blood pressure (BP) medications at bedtime instead of in the morning. Nighttime dosing leads to better control and lowers the risk of major cardiovascular events.1,2


B: Based on a well-done randomized clinical trial (RCT) and a subgroup analysis.

Hermida RC, Ayala DE, Mojón A, et al. Influence of circadian time of hypertension treatment on cardiovascular risk: results of the MAPEC study. Chronobiol Int. 2010;27:1629-1651.

Hermida RC, Ayala DE, Mojón A, et al. Influence of time of day of blood pressure-lowering treatment on cardiovascular risk in hypertensive patients with type 2 diabetes. Diabetes Care. 2011;34:1270-1276.


  • A 60-year-old man has struggled to get his BP under control despite the use of 3 anti-hypertensives. Is there anything you can recommend to improve his BP control and lower his cardiovascular risk?
  • You prescribe hydrochlorothiazide for a 55-year-old woman with newly diagnosed hypertension. What can you tell her about how to take the medication to maximize its beneficial effects?

Management of hypertension often centers around BP measurements taken in a doctor’s office during the day, although both BP and metabolism fluctuate with circadian rhythms. Most people experience an increase in pressure during the day, with peaks in the morning and evening, followed by a decline in BP while they sleep at night.3

The focus belongs on nighttime BP
Sleeping BP is getting considerable attention, particularly the phenomenon of nondipping. Commonly defined as a <10% decline in systolic pressure during sleep, nondipping is associated with an increased risk of cardiovascular events, such as heart attack and stroke.4 What’s more, mean BP during the night is a better predictor of cardiovascular disease (CVD) risk than BP while the patient is awake.5,6

Evidence suggests that taking an anti-hypertensive medication at night increases its therapeutic effect,7 yet most patients take it in the morning.8 The study detailed in this PURL was designed to investigate whether bedtime dosing significantly affects BP control and CVD risk.

STUDY SUMMARY: Bedtime dosing benefits patients, and there’s no downside

The MAPEC study was an open-label RCT conducted at a single center in Spain.1 Patients were enrolled if they had a diagnosis of either untreated hypertension (based on ambulatory BP monitoring [ABPM] criteria) or resistant hypertension (uncontrolled on ≥3 optimally dosed antihypertensive medications). Exclusion criteria included pregnancy, a history of drug/alcohol abuse, night shift work, acquired immune deficiency syndrome, type 1 diabetes, secondary hypertension, and a previous CVD diagnosis.

Patients were randomly assigned to one of 2 time-of-day dosing groups: morning dosing of all their BP medications (n=1109) or dosing of ≥1 BP medications at bedtime (n=1092). ABPM—in which patients wore a monitor that recorded their BP every 20 minutes during the day and every 30 minutes at night for 48 hours—was conducted once a year, or more frequently when medication adjustments occurred. The use of a specific drug was not required, but physicians were instructed to adjust medications according to a study-specific ABPM protocol.

Patients were followed for a mean of 5.6 years for the endpoints of CVD events and mortality. These endpoints were assessed by researchers blinded to patients’ treatment assignment.

At baseline, the 2 groups were similar in age (mean of 55 years), percentage of men (48%), presence of comorbidities, and baseline clinic and ambulatory BP. Throughout the study, patients in the bedtime dosing group had lower mean asleep systolic and diastolic BP, a lower prevalence of a non-dipping pattern, and a higher prevalence of controlled ambulatory BP. The bedtime group also had a lower risk of total CVD events (relative risk [RR]=0.39; 95% confidence interval [CI], 0.29-0.51; P<.001) and major CVD events (RR=0.33; 95% CI, 0.19-0.55; P<.001), and fewer overall deaths (4.16/1000 vs 2.11/1000 patient-years; P=.008) (TABLE). To prevent one CVD event, 63 patients would need to take their BP medication at bedtime instead of in the morning for one year. To prevent one death, 488 patient would need to adhere to the nighttime schedule for one year.

A subgroup analysis of patients with type 2 diabetes (n=448)2 had similar results: For this population, too, bedtime dosing led to lower asleep BP, a lower prevalence of a non-dipping pattern, and a higher prevalence of controlled ambulatory BP, as well as a lower risk of total CVD events, major CVD events, and CVD-related death. The differences persisted after correction for the use of statins and aspirin. Among those in this subgroup analysis, 29 patients would need to take their BP medications at bedtime for one year to prevent one CVD event, and 263 patients would need to be treated for one year to prevent one death.


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