AB0695 LONG-TERM OUTCOMES OF AFRICAN AMERICAN PATIENTS WITH SYSTEMIC SCLEROSIS-RELATED INTERSTITIAL LUNG DISEASE

Abstract

Background Observational studies have demonstrated that african american patients with Systemic Sclerosis (SSc) have a more unfavorable prognosis compared with non-African americans. However, no studies have evaluated racial disparities using data from a randomized controlled trial (RCT) where all patients have equal access to care and standard treatment and follow-up during the trial. Objectives To compare morbidity and mortality in african american and non-African american patients who participated in the Scleroderma Lung Study (SLS) I and II.1,2 Methods SLS I randomized 158 SSc patients with interstitial lung disease (ILD) from 13 US SSc centers to 1 year of oral CYC (cyclophosphamide) versus placebo. SLS II randomized 142 SSc-ILD participants from 14 US SSc centers to 1 year of oral CYC, followed by 1 year of placebo, versus 2 years of mycophenolate (MMF). Up to 12 (SLS I) and 5 (SLS II) years after randomization, we contacted enrolled patients or designated surrogates to assess the following: mortality, cause of mortality, and development of organ failure. We used cox proportional hazard modeling to determine the variables associated with survival. Results Baseline characteristics of the SLS I and II cohorts were similar. In SLS I, african american participants (N=26) were younger than non-African american participants (N=132) (43.1 vs. 49.5 years, P=0.015). In SLS II, african american participants (N=33) had slightly increased baseline forced vital capacity (FVC) (69.2 vs 65.6, P=0.038), compared with non-American american participants (N=109). There were no significant baseline differences in the extent of cutaneous sclerosis (Modified Rodnan Skin Score [MRSS]), presence of diffuse cutaneous disease or serological profiles between racial groups. After adjusting for age, MRSS, FVC, there was no difference in long-term mortality outcomes (due to all causes or due to respiratory failure) in african american versus Non-African american SSc-ILD participants in SLS I or II (Figure 1). There was also no difference in time to the development of respiratory failure in african american versus Non-African american SSc-ILD participants in SLS I or II. Conclusion Data from two of the largest RCTs in SSc-ILD demonstrated that african american patients with SSc-ILD have similar morbidity and mortality outcomes compared with non-African american SSc-ILD patients, even after adjusting for age and baseline disease severity. These findings contrast with the racial disparities described in previous observational studies and warrant further investigation.