The effect of Mid-Day Sleep on blood pressure levels in patients with arterial hypertension

Abstract

Study objectives: Lifestyle changes decrease blood pressure (BP) levels by 3-5 mmHg in hypertensive patients. We assessed the effect of mid-day sleep on BP levels in hypertensive patients.

Methods: We prospectively studied two hundred and twelve hypertensive patients. Mid-day sleep duration, lifestyle habits, anthropometric characteristics, office BP, ambulatory BP monitoring, pulse wave velocity (PWV), augmentation index (AI) were recorded. A standard echocardiographic evaluation was performed.

Results: 53.8% were females, mean age was 62.5±11.0 years and mean body mass index was 28.9±5.4kg/m². Mean average 24h systolic and diastolic BP (SBP & DBP) was 129.9±13.2/76.7±7.9 mmHg respectively. The majority was non-smokers (70.3%) and did not have diabetes (74.7%). The mean midday sleep duration was 48.7±54.3 min. Average 24h SBP (127.6±12.9 mmHg vs 132.9±13.1 mmHg), average daytime SBP & DBP were lower in patients who sleep at midday, compared to those who do not (128.7±13/76.2±11.5 vs 134.5±13.4/79.5±10.4 mmHg) (p<0.005). The effect was not correlated to the dipping status. Midday sleep duration was negatively correlated with average 24h SBP & daytime SBP. In a linear regression model, for every 60 min of midday sleep, 24h average SBP decreases by 3 mmHg (p<0.001). There were no differences in the number of antihypertensive medications, PWV, AI or echocardiographic indices between study groups.

Conclusions: Mid-day sleep significantly decreases average 24h and daytime SBP/DBP in hypertensives. Its effect seems to be as potent as other well-established lifestyle changes and is independent of dipping status.

Keywords: Mid-day sleep; arterial hypertension; lifestyle changes.