Comparison of clinical characteristics and outcomes between combined pulmonary fibrosis and emphysema associated with usual interstitial pneumonia pattern and non-usual interstitial pneumonia

Abstract

Background: Recently, combined pulmonary fibrosis and emphysema (CPFE) has been recognized worldwide. However, actually CPFE had a variety of extent of emphysema or pulmonary fibrosis. Objectives: The objectives of this study were to compare the clinical characteristics and outcomes between CPFE associated with usual interstitial pneumonia pattern (UIP) and CPFE with non-UIP divided based on chest high resolution computed tomography (HRCT) images, as well as to elucidate prognostic factors. Methods: A cohort of 57 CPFE and 64 IPF patients at a single institution was analyzed retrospectively. The HRCT imaging patterns of definite UIP pattern and possible UIP pattern were defined as UIP, and inconsistent with UIP pattern as non-UIP. Clinical characteristics and outcomes were compared in 3 subgroups with CPFE/UIP, CPFE/non-UIP, and IPF alone, respectively. The prognostic factors were performed using Cox proportional hazards. Results: The incidences of primary lung cancer and acute exacerbation (AE) were 10.4%/10.9% in CPFE/UIP, 0%/27.3% in CPFE/non-UIP, and 6.3%/35.9% in IPF, respectively. The survival in CPFE/UIP had significantly worse than that in other 2 subgroups (CPFE/non-UIP, IPF) (P = 0.011, P = 0.043). The multivariate Cox regression model showed that the prognostic factors of CPFE were UIP pattern and high-composite physiologic index (CPI). CPI thresholds of 45 provided the greatest prognostic separation in patients with CPFE. CPFE/UIP with high-CPI (CPI ≥ 45) had a worst prognosis compared with the other groups. Conclusions: This study demonstrated that the presence of UIP pattern and high-CPI in CPFE patients were associated with poorer mortality. (Sarcoidosis Vasc Diffuse Lung Dis 2015; 32: 129-137)