Pulmonary Hypertension in Chronic Hypersensitivity Pneumonitis

Background The purpose of this study was to evaluate the prevalence and outcomes of pulmonary hypertension in chronic hypersensitivity pneumonitis and to examine the relationship between pulmonary function tests and pulmonary hypertension. Methods We conducted a retrospective review of 120 patients with hypersensitivity pneumonitis seen at two centers for pulmonary diseases over a 5-year interval and identified patients with chronic hypersensitivity pneumonitis for whom both pulmonary function tests and Doppler echocardiography data were available. Results Chronic hypersensitivity pneumonitis was identified in 83 patients and Doppler echocardiography data were available for 73 of them. Pulmonary hypertension (sPAP ≥ 50 mmHg) was detected in 14 patients (19%), and was associated with a greater risk of death (median survival = 23 months vs. 98 months; P = 0.003). Patients with pulmonary hypertension were older and had a significantly decreased PaO 2 . There was a weak correlation between pulmonary function parameters and the underlying sPAP, with significance for FVC, FEV 1 , and PaO 2 and inversely with PaCO 2 . Conclusions Using Doppler echocardiography for evaluation, pulmonary hypertension seems to be common in patients with chronic hypersensitivity pneumonitis, significantly impacts survival, and correlates with FVC, FEV 1 , and PaO 2 and inversely with PaCO 2 .