Overall mortality in combined pulmonary fibrosis and emphysema related to systemic sclerosis

Objectives: This multicentre study aimed to investigate the overall mortality of combined pulmonary fibrosis and emphysema (CPFE) in systemic sclerosis (SSc) and to compare CPFE-SSc characteristics with those of other SSc subtypes (with interstitial lung disease - ILD, emphysema or neither). Methods: Chest CTs, anamnestic data, immunological profile and pulmonary function tests of patients with SSc were retrospectively collected. Each chest CT underwent a semiquantitative assessment blindly performed by three radiologists. Patients were clustered in four groups: SSc-CPFE, SSc-ILD, SSc-emphysema and other-SSc (without ILD nor emphysema). The overall mortality of these groups was calculated by Kaplan-Meier method and compared with the stratified log-rank test; Kruskal-Wallis test, t-Student test and χ 2 test assessed the differences between groups. P<0.05 was considered statistically significant. Results: We enrolled 470 patients (1959 patient-year); 15.5 % (73/470) died during the follow-up. Compared with the SSc-ILD and other-SSc, in SSc-CPFE there was a higher prevalence of males, lower anticentromere antibodies prevalence and a more reduced pulmonary function (p<0.05). The Kaplan-Meier survival analysis demonstrates a significantly worse survival in patients with SSc-CPFE (HR vs SSc-ILD, vs SSc-emphysema and vs other-SSc, respectively 1.6 (CI 0.5 to 5.2), 1.6 (CI 0.7 to 3.8) and 2.8 (CI 1.2 to 6.6). Conclusions: CPFE increases the mortality risk in SSc along with a highly impaired lung function. These findings strengthen the importance to take into account emphysema in patients with SSc with ILD.