A Comparison of Survival in IPF, Emphysema and CPFE Syndrome

Background: Coexistent emphysema and usual interstitial pneumonia (UIP) on CT is increasingly recognised. It is unclear if combined pulmonary fibrosis and emphysema syndrome (CPFE) is a distinct clinical entity with an impact on survival. Aim: To compare survival rates of patients with idiopathic pulmonary fibrosis (IPF), CPFE and emphysema. Methods: Retrospective cohort study of 509 patients with COPD or IPF and a CT scan performed between 2009-2020 from 4 UK NHS sites. Demographic and clinical data was extracted from electronic medical records, including initial CT scan report and date, initial pulmonary function tests (ANOVA test - * denotes p<0.05 across groups) and date of death/ follow-up censor point. Patients were grouped from CT reports as IPF, CPFE or Emphysema. Kaplan Meier Survival Estimates were performed using STATA v16. Results: Patients were grouped as: -IPF (n=317. At CT: mean age 73.3 years [SD 9.2]; 64.4% male; mean FEV1 2.16L [SD 0.66]*, mean FVC 2.68L [SD 0.84]*). 43.2% received antifibrotic therapy. -CPFE (n=109. At CT: mean age 72.2 years [SD 9.3]; 67.9% male; mean FEV1 2.13L [SD 0.73]*; mean FVC 3.00L [SD 1.00]*). -Emphysema (n=83. At CT: mean age 65.6 years [SD 10.6]; 66.3% male; mean FEV1 1.61L [SD 0.67]*; mean FVC 3.12L [SD 0.86]*). Figure 1 shows Kaplan Meier Survival Estimates. Conclusion: Co-existent emphysema and fibrosis is associated with worse survival than emphysema alone - CPFE has a survival trajectory comparable to IPF.