The clinical characteristics of patients with pulmonary hypertension combined with obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is one cause of pulmonary hypertension (PH) and can also emerge along with PH. The clinical diagnosis and treatment of OSA in patients with PH are still controversial. The purpose of this clinical observation study was to observe and summarize the incidence and clinical characteristics of OSA in patients with PH and to explore possible predictors of PH combined with OSA.

Patients with PH diagnosed by right heart catheterization who underwent overnight cardiorespiratory monitoring from December 2018 to December 2020 were enrolled. OSA was defined as an apnoea-hypopnoea index of ≥ 5/h with ≥ 50% of apnoeic events being obstructive. Baseline clinical characteristics and parameters were collected to compare PH patients with and without OSA. Logistic regression analysis was run to determine the risk factors for OSA in PH patients.

A total of 35 (25%) of 140 patients had OSA. OSA is relatively frequent in patients with PH, especially in patients with chronic thromboembolic pulmonary hypertension and patients with lung disease- or hypoxia-associated PH. The patients who had OSA were mostly male and had a higher age and a lower daytime arterial oxygen pressure. Logistic regression analysis found that older age, male sex, and lower daytime arterial blood oxygen pressure correlated with OSA in PH patients.

OSA is common in patients with PH. Lower daytime arterial oxygen pressure is a risk factor for OSA in older male patients with PH.