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Introduction Non-White individuals generally present with distinct and more severe systemic sclerosis (SSc) phenotypes compared to White individuals. We further characterized and compared demographic, clinical, and serological characteristics, as well as mortality and disease progression, of Canadian SSc patients according to race/ethnicity background.Material and Methods Participants enrolled in the Canadian Scleroderma Research Group cohort study who self-identified to a single race/ethnicity were included. Demographic, clinical and serological characteristics at baseline were compared using ANOVA, chi-square or Kruskal-Wallis rank sum test as appropriate. Kaplan-Meier curves were used to estimate survival probabilities at 1, 5 and 10 years of follow-up. The effect of race/ethnicity on overall mortality, SSc-specific mortality and progression of lung disease was estimated using Cox regression.Results Of 1477 eligible participants, 1345 (91.1%) identified as White, 55 (3.7%) as Indigenous, 22 (1.5%) as East/Southeast Asian, 20 (1.4%) as Middle Eastern, 16 (1.1%) as Black, 12 (0.8%) as South Asian, and 7 (0.5%) as Latin American. At baseline, Black individuals had the highest mean modified Rodnan skin score (18.4 ± 12.0), and the highest prevalence of diffuse subtype (69%), telangiectasias (92%), myositis (44%), and renal crisis (13%), with the lowest mean forced vital capacity (73.7 ± 16.8 % predicted) and DLCO (54.5 ± 21.7 % predicted). Black patients also had the lowest overall survival probabilities at 1 and 5 years (85% and 57%) (see table 1). Indigenous individuals were more often affected by lower gastrointestinal manifestations compared to other race/ethnicities, with the highest prevalence of malabsorption (24%), small intestinal bacterial overgrowth requiring antibiotics (15%), need for hyperalimentation (11%) and pseudo-obstruction (9%). East/Southeast individuals were less frequently affected by Raynaud’s (90%) and digital ulcers (29%), while Middle Eastern individuals had the lowest prevalence of arthritis (12%), calcinosis (11%), telangiectasias (40%), and interstitial lung disease (24%). White individuals had the lowest prevalence of diffuse SSc (33%) and telangiectasias (44%), and had numerically lower ILD progression rates compared to other ethnicities.Conclusions Race/ethnicity was associated with distinct SSc phenotypes. Potential limitations include referral/selection bias, and the fact that we did not account for differences in age/sex distributions between race/ethnicities. Further research could clarify how race/ethnicity may be used to guide screening and management of SSc complications, thus representing an opportunity to personalize care.Abstract P.387 Table 1