Treat hard and early in SSc-ILD: milde ILD ist immer noch ILD

Abstract

Background: Interstitial lung disease (ILD) is the leading cause of death in systemic sclerosis (SSc). According to expert statements, not all SSc-ILD patients require pharmacological therapy. Objectives: To describe disease characteristics and disease course in untreated SSc-ILD patients in two well characterised SSc-ILD cohorts. Methods: Patients were classified as treated if they had received a potential ILD-modifying drug. ILD progression in untreated patients was defined as (1) decline in forced vital capacity (FVC) from baseline of ≥ 10% or (2) decline in FVC of 5%–9% associated with a decline in diffusing capacity for carbon monoxide (DLCO) ≥ 15% over 12 ± 3 months or (3) start of any ILD-modifying treatment or (4) increase in the ILD extent during follow-up. Multivariable logistic regression was performed to identify factors associated with non-prescription of ILD-modifying treatment at baseline. Prognostic factors for progression in untreated patients were tested by multivariate Cox regression. Results: Of 386 SSc-ILD included patients, 287 (74%) were untreated at baseline. Anticentromere antibodies (OR: 6.75 (2.16–21.14), p = 0.001), limited extent of ILD (OR: 2.39 (1.19–4.82), p = 0.015), longer disease duration (OR: 1.04 (1.00–1.08), p = 0.038) and a higher DLCO (OR: 1.02 (1.01–1.04), p = 0.005) were independently associated with no ILD-modifying treatment at baseline. Among 234 untreated patients, the 3 year cumulative incidence of progression was 39.9% (32.9–46.2). Diffuse cutaneous SSc and extensive lung fibrosis independently predicted ILD progression in untreated patients.