Pulmonary arterial enlargement predicts long-term survival in COPD patients

Rationale Pulmonary artery enlargement (PAE) is associated with exacerbations in Chronic Obstructive Pulmonary Disease (COPD) and with survival in moderate to severe patients. The potential role of PAE in survival prediction has not been compared with other clinical and physiological prognostic markers. Methods In 188 patients with COPD, PA diameter was measured on a chest CT and the following clinical and physiological parameters registered: age, gender, smoking status, pack-years history, dyspnea, lung function, exercise capacity, Body Mass Index, BODE index and history of exacerbations in year prior to enrolment. Proportional Cox regression analysis determined the best predictor of all cause survival. Results During 83 months (+/- 42), 43 patients died. Age, pack-years history, smoking status, BMI, FEV1%, six minute walking distance, Modified Medical Research Council dyspnea scale, BODE index, exacerbation rate prior to enrollment, PA diameter and PAE (diameter >= 30mm) were associated with survival. In the multivariable analysis, age (HR: 1.08; 95% CI: 1.03 +/- 1.12, p< 0.001) and PAE (HR: 2.78; 95% CI: 1.35 +/- 5.75, p = 0.006) were the most powerful parameters associated with all-cause mortality. Conclusions In this prospective observational study of COPD patients with mild to moderate airflow limitation, PAE was the best predictor of long-term survival along with age.