Obstructive sleep apnoea treatment and blood pressure: which phenotypes predict a response? A systematic review and meta-analysis

Abstract

The treatment for obstructive sleep apnoea (OSA) with continuous positive airway pressure (CPAP) or mandibular advancement devices (MADs) is associated with blood pressure (BP) reduction; however, the overall effect is modest. The aim of this systematic review and meta-analysis of randomised controlled trials (RCTs) comparing the effect of such treatments on BP was to identify subgroups of patients who respond best to treatment.The article search was performed in three different databases with specific search terms and selection criteria. From 2289 articles, we included 68 RCTs that compared CPAP or MADs with either passive or active treatment. When all the studies were pooled together, CPAP and MADs were associated with a mean BP reduction of −2.09 (95% CI −2.78– −1.40) mmHg for systolic BP and −1.92 (95% CI −2.40– −1.43) mmHg for diastolic BP and −1.27 (95% CI −2.34– −0.20) mmHg for systolic BP and −1.11 (95% CI −1.82– −0.41) mmHg for diastolic BP, respectively. The subgroups of patients who showed a greater response were those aged <60 years (systolic BP −2.93 mmHg), with uncontrolled BP at baseline (systolic BP −4.14 mmHg) and with severe oxygen desaturations (minimum arterial oxygen saturation measured by pulse oximetry <77%) at baseline (24-h systolic BP −7.57 mmHg).Although this meta-analysis shows that the expected reduction of BP by CPAP/MADs is modest, it identifies specific characteristics that may predict a pronounced benefit from CPAP in terms of BP control. These findings should be interpreted with caution; however, they are particularly important in identifying potential phenotypes associated with BP reduction in patients treated for OSA.

Diagnostic and Therapeutic Approach to Sleep Disorders, High Blood Pressure and Cardiovascular Diseases: A Consensus Document by the Italian Society of Hypertension (SIIA)

“…Recent meta-analyses indicate a significant but small reduction in BP values in OSA patients treated with CPAP [65][66][67], with more evident effects on patients with resistant hypertension and on overnight BP values. This is interesting because the role of nocturnal BP in the development of cardiovascular diseases and its association with cardiovascular mortality and morbidity both in hypertensive patients and in the general population has been confirmed in several longitudinal and population studies [68]. In addition to higher baseline BP values, excessive daytime sleepiness and, in particular, increased treatment compliance are also associated with increased positive effects of CPAP treatment on BP [69,70].…”

“…Oral devices are indicated for the treatment of mild to moderate OSA and their effect on BP values is promising, similar to that obtained with CPAP according to some studies. Recently, a meta-analysis [68] A subgroup analysis showed that patients with higher BP values prior to treatment, patients < 60 years of age, and patients with higher hypoxic load were more likely to exhibit a more pronounced hypotensive effect in response to CPAP treatment.…”

Cardiovascular Disorders Triggered by Obstructive Sleep Apnea—A Focus on Endothelium and Blood Components

“…A better effect of CPAP was observed in the resistant hypertension subjects −5.40 mmHg and −3.86 mmHg respectively [ 75 ]. In the subjects with severe oxygen desaturations (SpO2 < 77%) with good CPAP adherence the reduction of systolic blood pressure was observed [ 76 ]. Severe desaturations but not AHI were associated with better hypotensive response of CPAP.…”

Mandibular Advancement Devices for OSA: An Alternative to CPAP?

“…It greatly improves objective indices of OSA (e.g., apnea-hypopnea index-AHI/hour), and has significant beneficial effects on symptoms including daytime sleepiness and quality of life [8]. There is also some evidence that CPAP has beneficial cardiovascular effects, with studies showing improvements in blood pressure [9][10][11]. However, the literature is inconsistent regarding the extent of potential cardiovascular benefit conferred by CPAP.…”