Research demonstrates that Black Americans with MS experience more aggressive disease and a higher lesion burden when compared with White Americans, but the factors associated with these disparities have not been examined. To determine factors that impact racial gaps in MS ambulatory impairment, investigators performed an analysis of 1,795 patients with relapsing-remitting MS at a single center between 2008-2015. Mediating factors of interest included median household income, BMI, hypertension, and smoking status; covariates included age, sex, disease duration, and disease-modifying therapy (DMT) status and were assessed for baseline and change-over-time disparities. Black patients had significantly slower Timed 25 Foot Walk speeds (4.6 vs 5.0 ft/s; P=4×10-7), shorter disease duration (7.6 vs 9.6 years; P=.003), less DMT usage (62% vs 71%; P=.007), and greater hypertension burden (30% vs 17%; P = .00002); they were also more likely to live in lower-income neighborhoods ($44,100 vs $56,491; P = 3×10-19) and were less likely to have ever smoked (36% vs 51%; P = .0004). Additional research is needed to increase understanding of the root causes of racial disparities in MS, the investigators noted.