Variable prevalence of pulmonary hypertension in patients with advanced interstitial pneumonia

Background Pulmonary hypertension may occur in patients with interstitial pneumonia and is associated with increased mortality. We sought to determine the prevalence of pulmonary hypertension in sub-groups of patients with interstitial pneumonia and to investigate possible associations between pulmonary vascular hemodynamics and pulmonary function. Methods The presence or absence of pulmonary hypertension was assessed in 70 patients with advanced interstitial pneumonia who underwent right heart catheterization. The associations of pulmonary hypertension with clinical characteristics and pulmonary function tests were analyzed. Results The prevalence of pulmonary hypertension in patients with idiopathic interstitial pneumonia was 29% vs 64% in patients with connective tissue disease-interstitial pneumonia ( p = 0.013). African American patients had a significantly higher prevalence of pulmonary hypertension in the entire study population (81% vs 22%, p < 0.001) and in the idiopathic interstitial pneumonia group (70% vs 19%, p < 0.01). Regression analyses revealed no association between mean pulmonary artery pressure (mPAP) and forced vital capacity or mPAP and diffusion capacity of the lung for carbon monoxide in the entire cohort or in sub-groups of patients. Conclusions African American patients and patients with connective tissue disease-interstitial pneumonia had a high prevalence of pulmonary hypertension. Non-African American patients with advanced idiopathic interstitial pneumonia (including idiopathic pulmonary fibrosis) had a low prevalence of pulmonary hypertension.