Nasal CPAP reduces systemic blood pressure in patients with obstructive sleep apnoea and mild sleepiness

Abstract

Background: A randomised controlled study was undertaken to examine the effect of nasal continuous positive airway pressure (CPAP) on 24 hour systemic blood pressure (BP) in patients with obstructive sleep apnoea (OSA). Methods: Patients were fitted with an ambulatory BP measuring device as outpatients during normal activities and recorded for 24 hours before starting therapeutic or subtherapeutic (4 cm H 2 O) CPAP treatment. BP monitoring was repeated before completion of 12 weeks of treatment. The primary end point was the change in 24 hour mean BP. Results: Twenty three of 28 participants in each treatment arm completed the study. There was no significant difference between the two groups in age, body mass index, Epworth Sleepiness Score, apnoea-hypopnoea index, arousal index, and minimum SaO 2 . Twenty four patients were hypertensive. The pressure in the therapeutic CPAP group was 10.7 (0.4) cm H 2 O. CPAP usage was 5.1 (0.4) and 2.6 (0.4) hours/night for the therapeutic and subtherapeutic CPAP groups, respectively (p,0.001). After 12 weeks of treatment there were significant differences between the two CPAP groups in mean (SE) changes in 24 hour diastolic BP (

Aryl hydrocarbon receptor nuclear translocator-like (BMAL1) is associated with susceptibility to hypertension and type 2 diabetes

“…Altered levels of Bmal1 may contribute to hypertension in SHR through aberrant sleep pattern and changes in the macrostructure of sleep, which have been documented in SHR (39) and Bmal1 Ϫ/Ϫ mice (40), and are similar to disruptions reported in hypertensive patients (41). A causative link between obstructive sleep apnea and hypertension exists in humans (42,43).…”

Validation of a portable recording device (ApneaLink) for identifying patients with suspected obstructive sleep apnoea syndrome

“…Patients were recruited if they had presented with daytime sleepiness that interfered with daytime function or two of the following symptoms: choking or gasping during sleep, recurrent awakenings from sleep, unrefreshed sleep, daytime fatigue and impaired concentration. 13,14 All subjects underwent a simultaneous sleep study with the portable AL device and in-lab diagnostic PSG (Alice 4; Healthdyne).…”

“…14,15 The PSG data were manually scored by an experienced investigator blinded to the clinical data and the results of the AL. Sleep stages were scored according to standard criteria by Rechtschaffen and Kales.…”

The Price of Obstructive Sleep Apnea-Hypopnea: Hypertension and Other Ill Effects

“…Predefined meta-regression analyses revealed falls of 24-h mean BP by 0.89 per 10 event/h increment in AHI and 1.38 per 1 h/night increment in CPAP use. 83 Three additional randomized controlled trials published after the inclusion period of the meta-analyses were largely confirmatory, [84][85][86] although the study conducted in mostly untreated hypertensive sleepy patients with OSAH showed a substantial and statistically significant reduction in clinic BPs (−6.7/−4.9 mm Hg, systolic/diastolic). 85 The meta-analyses, despite the limitations of the existing trials, suggest that the BP lowering reported with CPAP may not be the only or even the most important beneficial effect on cardiovascular risk of treating OSAH (see section entitled "Effects of treatment of OSAH on cardiovascular diseases and insulin resistance").…”