Asleep home blood pressure monitoring in obstructive sleep apnea

Abstract

Obstructive sleep apnea (OSA) is known to be related to nocturnal blood pressure (BP) and nondipping hypertension. This pilot study evaluated night-time BP assessed using a home monitor in patients with OSA. Patients referred to a sleep clinic were subjected to polysomnography, clinic BP measurements, and home BP monitoring using a device that allows daytime (3 days, two duplicate readings per day) and automated night-time BP measurement (3 nights, three readings per night). Thirty-nine patients were included [72% men, mean age 48.7±10.8 years, clinic BP 131.2±19.6/84.1±11.9 mmHg, apnea-hypopnea index (AHI): 35.2±25.7]. All BP measurements were significantly correlated with the polysomnography indices. There was a consistent trend toward stronger correlations of the night-time diastolic home BP with the AHI (r=0.56), the duration of desaturation (0.53), and the maximum (-0.57) and minimum (-0.48) arterial oxygen saturation (all P<0.001). In stepwise multivariate analysis (independent variables age, sex, body weight, smoking status, and BP parameters), the AHI was associated independently with weight and night-time diastolic home BP (R=0.53). In patients with OSA, the assessment of night-time BP using a home monitor appears to be feasible and related to the severity of OSA. Given the wide availability of home BP monitoring in clinical practice, this method appears to be useful in the evaluation of BP in patients with OSA.