Hispanic Americans and African Americans with multiple sclerosis have more severe disease course than Caucasian Americans.

Whether disease course in Hispanic Americans (HA) with multiple sclerosis (MS) is different from Caucasian Americans (CA) or African Americans (AA) is unknown. We compared MS severity in the three main ethnic populations in our tertiary MS clinics using disease duration-adjusted rank score of disability: Patient-Derived Multiple Sclerosis Severity Score (P-MSSS). The age- and gender-adjusted P-MSSS was significantly higher in HA (3.9 ± 2.6) and AA (4.5 ± 3.0) compared to CA (3.4 ± 2.6; p < 0.0001 for both). Adjusting for insurance did not change these results. These findings suggest that HA, as AA, have more rapid disability accumulation than CA.