0538 Untreated Obstructive Sleep Apnea Contributes to Mortality in Patients with Group 1 Pulmonary Hypertension

Abstract Introduction The World Health Organization (WHO) has categorized pulmonary hypertension (PH) in five groups. Obstructive sleep apnea (OSA) is an independent cause of group 3 PH. The prevalence of OSA in PH patients is approximately 20% and untreated OSA may contribute to pulmonary vascular remodeling, exacerbating PH. Regular use of positive airway pressure (PAP) can improve pulmonary artery pressures. We hypothesized that untreated OSA is associated with mortality in all five groups of PH, and that mortality is reduced with PAP therapy. Methods We performed a retrospective chart review of the PH patient registry at Mayo Clinic Jacksonville, comprised of 696 patients classified per WHO classification of PH. Mortality in each WHO group of PH was abstracted as well as the presence of OSA as a comorbidity. Compliance with positive airway pressure therapy (PAP) was assessed across all patients with OSA. Results Patients in the registry were followed for a mean of 101.2 months. The mortality across all groups was 36.8%, ranging from 22.6% in group 4 to 64.3% in group 5. OSA was present in 46.9% patients, and it ranged from 33% in group 5 to 58% in group 2. Mortality did not vary significantly in the patients with OSA versus those without OSA (p=0.56). Of patients with OSA, 45.9% was deemed compliant with PAP therapy. Overall, the compliant patients had reduced mortality compared to the noncompliant ones (p=0.045), however this significance was due to pronounced effect in group 1 patients only. Conclusion Almost half of PH patients from our registry had OSA. Compliance with PAP therapy was associated with lesser mortality, primarily due to the effect seen in Group 1 PH patients. Support (if any)