This study investigates the association between obstructive sleep apnea (OSA) and pulmonary hypertension (PH), focusing on the relationship between OSA severity and pulmonary arterial pressures in adult patients.

This prospective, observational, cross-sectional study will be conducted in the pulmonology and sleep medicine departments of Assiut University. Patients diagnosed with OSA through overnight polysomnography will be assessed for the presence and severity of PH using echocardiography. The study aims to determine whether OSA serves as an independent risk factor for PH and whether the severity of OSA, as measured by apnea-hypopnea index (AHI) and oxygen desaturation index (ODI), correlates with echocardiographic indicators of PH. Data will be analyzed using standardized statistical methods to establish links between OSA severity and hemodynamic changes.

Inclusion Criteria:

Adults aged 18-65 years

Diagnosed with obstructive sleep apnea (OSA) by full-night polysomnography

Apnea-Hypopnea Index (AHI) ≥ 5 events/hour

Exclusion Criteria:

Secondary pulmonary hypertension due to:Chronic pulmonary diseases, Left ventricular heart disease and Chronic thromboembolic disorders

Use of pulmonary vasodilator therapy

Long-term oxygen therapy (LTOT)

Respiratory neuromuscular weakness

Chest wall deformities

End-organ failure (cardiac, renal, hepatic)

Malignancy

Obesity hypoventilation syndrome

Eligible participants are 18-65 years old and diagnosed with OSA (AHI ≥ 5 events/hour) confirmed through full-night polysomnographic sleep study. Patients will be stratified into mild (AHI 5-14), moderate (AHI 15-29), and severe OSA (AHI ≥ 30). Exclusion criteria include patients with secondary PH (from cardiac causes, chronic thromboembolic disease, or pulmonary conditions), chronic vasodilator therapy, long-term oxygen therapy, advanced organ failure, neuromuscular or chest wall deformities, obesity hypoventilation syndrome, or malignancy. The expected sample size is 55 patients, ensuring enough statistical power to detect associations. Demographic, clinical, echocardiographic, radiological, and sleep study parameters will be collected for each patient.