Combined Pulmonary Fibrosis and Emphysema: Clinicoradiological Parameters Associated with Fibrosis Patterns.

OBJECTIVE: To determine the relative frequency of conditions causing different types of fibrosis [usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP)] in combined pulmonary fibrosis and emphysema (CPFE), a newly defined disease. STUDY DESIGN: A cross-sectional observational study. Place and Duration of the Study: Department of Radiology, Tokat Gaziosmanpasa University, Tokat, Turkiye, from January 2023 to January 2025. METHODOLOGY: Based on HRCT images, the visualised fibrosis types were divided into two groups: UIP (n = 48) and NSIP (n = 46). Demographic data included age, gender, smoking history, and occupational history. The Charlson Comorbidity Index (CCI) score was calculated for each patient. The Kolmogorov-Smirnov test was used to assess the distribution of variables in the analyses. Categorical data were compared using the chi-square test and numerical data by Student's t-test. RESULTS: CPFE patients were divided into two groups: UIP pattern (n = 48) and NSIP pattern (n = 46). No significant differences were found between the groups in terms of age, gender, smoking, CCI, and high-risk occupation. When examining the relationship between pulmonary hypertension and demographic data in patients with CPFE, the mean age and CCI were significantly higher in the group with systolic pulmonary artery pressure (sPAP) ≥25 mmHg, as measured by echocardiography. Furthermore, in those with sPAP ≥25, haemoglobin and haematocrit levels were significantly lower, and urea levels were significantly higher. Similarly, in those with sPAP ≥25, diffusing capacity of the lungs for carbon monoxide levels were significantly lower. CONCLUSION: Although comorbidities were found to be significantly higher in the UIP pattern compared to the NSIP pattern, the CCI was similar. As more than half of patients with CPFE had elevated sPAP, pulmonary hypertension should also be considered when evaluating these patients. KEY WORDS: Pulmonary fibrosis, Emphysema, Usual interstitial pneumonia, Carbon monoxide, Diffusion test, Pulmonary artery pressure.