Sleep-disordered breathing in patients with group 1 and group 4 pulmonary hypertension

Sleep-disordered breathing (SDB) is frequently observed in patients with pulmonary hypertension (PH) and may contribute to disease progression through recurrent nocturnal hypoxemia. However, data comparing SDB characteristics between Group 1 pulmonary arterial hypertension (PAH) and Group 4 chronic thromboembolic pulmonary hypertension (CTEPH) remain limited.

This cross-sectional study included 51 patients with stable precapillary PH (24 Group 1 PAH and 27 Group 4 CTEPH). Demographic characteristics, clinical findings, laboratory parameters, polysomnographic data, and right heart catheterization measurements were evaluated. All patients underwent overnight polysomnography. Statistical analyses were performed using SPSS version 25.0.

The mean age of the study population was 55 years, and 66.7% were female. Obstructive sleep apnea syndrome (OSAS) was identified in 88.2% of patients. Nocturnal desaturation was observed in 60.8% of the cohort. The mean oxygen desaturation index (ODI) was 22.45 ± 20.24 events/hour among patients with OSAS and 2.82 ± 2.59 events/hour among those without OSAS. Severe OSAS was present in 55.6% of OSAS patients. Group 4 patients demonstrated significantly higher total apnea-hypopnea index (AHI) values than Group 1 patients (29.16 ± 24.37 vs. 17.65 ± 14.87 events/hour, p = 0.045). No significant differences were observed in most hemodynamic parameters according to OSAS status.

Sleep-disordered breathing is highly prevalent in patients with precapillary pulmonary hypertension. OSAS and nocturnal hypoxemia were common findings, particularly among Group 4 patients. Routine polysomnographic evaluation may facilitate early identification and appropriate management of sleep-disordered breathing in this population.