1316 Increased muscle involvement and younger age are distinctive features in dermatomyositis patients with skin of color

Prior dermatomyositis (DM) cohort studies have not had sufficient representation of patients with skin color (SOC). Our study investigated differences in clinical presentations and co-morbidities DM without SOC (i.e. White Non-Hispanic), (e.g. Black, Hispanic, Asian). We conducted a retrospective 130 seen outpatient dermatology clinics at University Texas Southwestern Parkland Health between January 2006 to October 2022. Compared (N=68), (N=62) were younger initial visit (median age: 44.5 vs. 54.5 years, p<0.0001), longer disease duration (6.5 14.5 months, p=0.002), was more predominantly female (95% 82%, p=0.02). also likely classical (73% 57% classical, p=0.07), poikiloderma the upper back (42% 25%, p=0.04), elevated muscle enzymes (77% 46%, p=0.0005), positive MRIs deltoid/femur (86% p=0.04) versus SOC. presented less often linear extensor erythema digits (13% 38%, p= 0.001), calcinosis cutis (16% 1%, p=0.003), internal malignancies (8% 21%, p=0.04). Multivariable analysis identified age (odds ratio (OR)=0.936/year, 95% confidence interval (CI) (0.904-0.969), p<0.001), subtype (OR=2.416 (CI: 1.048-5.572), absence (OR=4.293 1.621-11.370), p=0.003) as significant predictors observations that involvement suggest greater severity chronicity these patients.