CPAP Usage Reduces Cardiac Events, All-Cause Mortality in OSA

Patients with moderate to severe obstructive sleep apnea (OSA) and coronary artery disease (CAD) using continuous positive airway pressure (CPAP) therapy have reduced risk for major adverse cardiovascular events (MACE) and all-cause mortality, according to study findings published in the Journal of Clinical Sleep Medicine.

Previous studies show that CPAP usage can improve cardiovascular events and metabolic components in patients with OSA, but its effects on patients with concomitant CAD were not known. Researchers therefore conducted a systematic review and meta-analysis to investigate the effects of CPAP therapy on cardiovascular events in adults with moderate to severe OSA with CAD.

The reviewers searched PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov from inception through December 20, 2021, for randomized controlled trials (RCTs) and observational studies comparing CPAP with usual care in patients with moderate to severe OSA and CAD. Primary outcomes were MACE, all-cause mortality, acute coronary syndrome (ACS), heart failure readmission, repeat revascularization, and arrhythmia.

A total of 14 studies of patients with OSA and CAD (average age, 54 to 71 years; 77% to 96% male) were identified for analysis. In those studies, 9 to 1346 patients received CPAP, with 22 to 1341 patients included in the control groups. Follow-up ranged from 12 to 86 months for MACE outcomes.

In the 11 studies (n=5410) reporting on the association of CPAP with MACE, CPAP treatment was associated with a risk ratio (RR) of 0.87 (95% CI, 0.78-0.98; P =.02). In the 8 studies (n=5034) reporting on the association of CPAP with all-cause and cardiovascular death, CPAP was associated with a 23% reduction in all-cause and cardiovascular death risk.

In the 6 studies (n=4591) evaluating the association between CPAP and repeat revascularization, CPAP was not associated with repeat revascularization incidence, although a subgroup analysis showed a lower risk for repeat revascularization with the usage of 4 hours CPAP or more per night, with a risk ratio of 0.56 (95% CI, 0.34-0.92; P =.02). Usage of less than 4 hours per night did not significantly reduce the risk of repeat revascularization (RR, 1.15; 95% CI, 0.92-1.40; P =.23).

Three studies (n=2445) showed that CPAP therapy was associated with systolic and diastolic blood pressure improvements. One study also showed that CPAP use of approximately 5 hours per night over 3 months was associated with improved glucose and Homeostatic Model Assessment for Insulin Resistance (HOMA IR) in patients with OSA and CAD who were not diabetic.

With respect to limitations, the researchers noted that most studies involved nonsleepy patients with OSA, who have a better prognosis than symptomatic patients. In addition, the MACE definition differed across studies and the average follow-up time was 4 years.

Researchers concluded, “CPAP usage in patients with moderate to severe OSA and concomitant CAD was associated with a reduced risk of MACE and all-cause death. The better CPAP use exceeding 4h/night may add more benefits on MACE, repeat revascularization, and blood pressure.”

This article originally appeared on Pulmonology Advisor