Impact of positive airway pressure therapy on pulmonary artery pressures in obstructive sleep apnea or obesity hypoventilation syndrome: a systematic review and meta-analysis

Background There is limited and conflicting evidence on the impact of obstructive sleep apnea and its treatment with positive airway pressure (PAP) therapy on pulmonary hypertension (PH). Research Question Does treatment of OSA and obesity hypoventilation syndrome (OHS) with PAP therapy improve pulmonary artery pressures. Study Design and Methods A systematic review and random-effects meta-analysis was performed. PubMed, EMBASE, Scopus, Web of Sciences, EBSCO, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched using PRISMA guidelines. Studies reporting pulmonary artery pressure in patients with OSA and OHS pre- and post-PAP therapy were included. The primary outcome was post-PAP therapy change in pulmonary artery pressures with separate analyses on pulmonary artery systolic pressure and mean pulmonary artery pressure. Sensitivity analysis was performed to assess the impact of PAP therapy in patients with only OSA or OHS. Results Twenty-three studies, 20 observational and three randomized clinical trials, with 733 patients were included (19 with OSA, n=518 and 4 with OHS+OSA, n=215). Most patients had severe OSA. PAP therapy was associated with a mean reduction in pulmonary artery pressure of 5.96 mmHg (95% CI: 3.20, 8.73; p<0.0001). In patients with baseline PH (n=233), the reduction was 11.41 mmHg (95% CI: 8.66, 14.15; p<0.00001). The beneficial effect of PAP therapy was similar in OSA and OHS. There was no sex difference in the impact of PAP therapy. Heterogeneity was high across studies (I 2 >85%), reflecting differences in study design, patient populations, and methodologies. Conclusions PAP therapy reduces pulmonary artery pressures in patients with mostly severe OSA or OHS, with a more pronounced effect in those with baseline PH. As such, our findings may not apply to patients with milder degrees of OSA. While reductions in pulmonary artery pressures were observed in all groups, the low certainty necessitates cautious application of these findings in clinical practice. Systematic review and meta-analysis registration PROSPERO (CRD42024595312)