Incidence of pulmonary hypertension in COPD and its relation to inflammatory marker interleukin-1

Abstract

BackgroundMany COPD patients present with severe PH defined by a pulmonary vascular resistance (PVR) > 5 WU as measured by right heart catheterization (RHC), and inflammation is thought to be contributing strongly to pulmonary vascular remodeling in COPD besides hypoxia. Interleukin-1 (IL-1) is thought to be a major cytokine that may be involved in development of PH in these patients.ObjectiveThis study aimed to identify the incidence of PH in COPD and its relation to inflammatory marker IL-1.Patients and methodsOne-hundred COPD patients underwent echocardiography and serum IL-1 analysis, and patients with high probability of PH underwent pulmonary artery catheterization using Swan-Ganz catheter.ResultsThe mean serum IL-1 level was 82 pg/ml ± 22 pg/ml (the normal IL-1 serum level is known to be 0:5 pg/mL), 51% of the participants were categorized as having a low probability of PH, 35% was intermediate, and 14% was high. RHC results were as follows: mild combined pre- and postcapillary PH was diagnosed in 14.3% of the patients. Mild precapillary PH was found in 42.9%, making it the most common type. Severe combined pre- and postcapillary PH was noted in 21.4% of the patients. Severe precapillary PH was present in 14.3%. A significant positive correlations were observed between serum IL-1 and tricuspid regurgitation velocity (TRV) (r = 0.409, P < 0.001), estimated systolic pulmonary artery pressure (ESPAP) (r = 0.508, P < 0.001), and mean pulmonary artery pressure (mPAP) (r = 0.410, P = 0.140).ConclusionSerum IL-1 is a potent predictor of a high probability of PH in COPD patients, and there was significant positive correlation between serum IL-1 and echocardiographic findings and PH probability and RHC findings in COPD patients.