Bedtime regularization as a potential adjunct therapy for hypertension: a proof-of-concept study

Sleep irregularity is associated with elevated blood pressure (BP). Whether sleep regularity decreases BP is not known. We hypothesized that an intervention involving 2 weeks of sleep regularization would decrease BP in people with hypertension.

Eleven people with hypertension (four males/seven females, age: mean 53 [range 45-62 years]), body mass index (32 ± 6 kg/m²), but no other chronic disease were studied. We measured ambulatory BP and assessed sleep using actigraphy over a free-living baseline week. For the next 2 weeks, participants were asked to go to bed at the same time every night before reassessing their ambulatory BP. The standard deviations of bedtimes and sleep onset were used to measure variability. The minimal detectable change (MDC) in BP was calculated from 48 h of ambulatory BP monitoring to analyze individual responses.

Bedtime variability (32.4 ± SD 17 vs. 7 ± 10 min, p = .001) and sleep onset variability (30 ± 17 vs. 7 ± 8 min, p = .011) decreased following the intervention; no other sleep parameters changed. Bedtime regularization significantly reduced 24-h systolic BP (-4 ± 4 mmHg) and diastolic BP (-3 ± 3 mmHg), mainly due to reduced nighttime systolic BP (-5 ± 7 mmHg) and diastolic BP (-4 ± 5 mmHg), all p < .05. ≥50 per cent of participants decreased their BP by more than the MDC₉₅ for 24-h BP.

In this proof-of-concept study, 2 weeks of bedtime regularization decreased 24-h and nighttime BP in people with hypertension, suggesting that this may be a simple, yet low-risk, adjunctive strategy to control BP in many people with hypertension. This ought to be tested in a larger randomized controlled trial.