Radiographic fibrosis score predicts survival in systemic sclerosis-associated interstitial lung disease

Abstract

Background and objective: Interstitial lung disease (ILD) is a common pulmonary manifestation of systemic sclerosis (SSc). It is unknown whether radiographic fibrosis score predicts mortality in SSc-associated ILD (SSc-ILD). We retrospectively analysed patients with SSc-ILD to evaluate whether radiographic fibrosis score was a useful predictor of mortality.

Methods: We identified SSc-ILD patients evaluated at Kurashiki Central Hospital (Japan) from 2006 to 2016, and radiographic fibrosis scores based on the extent of reticulation and honeycombing on high-resolution computed tomography (HRCT) scanning were calculated by manually tracing around each fibrotic area. Independent predictors of overall survival were determined using the Cox proportional hazards model.

Results: The study included 48 patients, of whom 19 had usual interstitial pneumonia on HRCT. The median follow-up period was 56.6 months, and over the follow-up period 15 patients died. The 5-year survival was 72.4%. In the multivariate analysis, radiographic fibrosis score, age, being male and forced vital capacity were independently associated with an increased risk of death, while HRCT pattern was not.

Conclusion: A high radiographic fibrosis score was a poor prognostic factor in SSc-ILD. More widespread fibrosis was associated with an increased risk of death, independent of HRCT pattern.

Keywords: Japanese; high-resolution computed tomography; interstitial lung disease; radiographic pulmonary fibrosis; systemic sclerosis.