Prevalence, predictors, and survival in pulmonary hypertension related to end-stage chronic obstructive pulmonary...

The prevalence, prognostic importance, and factors that predict the presence and degree of pulmonary hypertension (PH) diagnosed with right heart catheterization (RHC) in patients with end-stage chronic obstructive pulmonary disease (COPD) remain unclear.

This retrospective study included 409 patients (61% women) with COPD/emphysema or α-1-antitrypsin deficiency who underwent lung transplant evaluation during 1991 to 2010. We analyzed the occurrence and degree of PH and compared demographics, oxygenation, lung function, hemodynamics, functional capacity, and survival in patients with and without PH. Prediction of PH was assessed using univariate and multivariate regression analysis.

The mean age at evaluation was 54 ± 7 years. All patients were in New York Heart Association functional class III-IV, with forced expiratory volume in 1 second of 23% ± 7% and total lung capacity of 126% ± 21% of predicted. PH was present in 146 (36%). The analysis excluded 53 (13%) with pulmonary venous hypertension (PVH). The distribution of the mean pulmonary artery pressure (mPAP) in patients with or without PH showed a unimodal normally distributed population, with a mean of 23.8 ± 6.0 mm Hg. Predictors of PH were partial pressures of oxygen and carbon dioxide. The 5-year survival rate was 37% in COPD patients with PH vs 63% in patients without PH (p = 0.016). Survival after lung transplantation did not differ (p = 0.37).

RHC verified PH in 36% of COPD patients. Hypoxemia and hypercapnia were associated with mPAP. PH is associated with worse survival in COPD, but PH does not influence the prognosis after lung transplantation.