ObjectiveTo observe the relationship of serum tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and C-reactive protein (CRP) with obstructive sleep apnea hypopnea syndrome (OSAHS) associated pulmonary hypertension (OSAHS-PH). MethodsFrom September 2013 to October 2014, 38 OSAHS patients, 32 OSAHS-PH patients and 35 healthy subjects were enrolled from the General Hospital of Ningxia Medical University. OSAHS was diagnosed by polysomnography. The pulmonary artery systolic pressure (PASP) was measured by echocardiograph, and the diagnose criteria for pulmonary hypertension was PASP≥40 mm Hg. Serum TNF-α, IL-6, CRP and endothelin 1 (ET-1) were detected by enzyme-linked immunosorbent assay. The correlation between TNF-α, IL-6, CRP, ET-1 and PASP was analyzed. ResultsThe serum levels of TNF-α, IL-6, CRP and ET-1 were remarkably different among three groups (F=55.34, 25.05, 23.85, 34.06 respectively; all P < 0.05). The levels of TNF-α, IL-6, CRP and ET-1 in the OSAHS group were higher than those in the healthy group, and lower than those in the OSAHS-PH group (all P < 0.05). The PASP was positively correlated with the levels of the four factors (r=0.755, 0.762, 0.747, 0.759 respectively; all P < 0.01). ConclusionThe levels of serum TNF-α, IL-6 and CRP are correlated with pulmonary hypertension and they may be involved in the process of OSAHS-PH.