Multiple sclerosis (MS) has a greater burden on black Americans compared to white Americans, according to a new study published in the journal Neurology. This is the case even after adjustments in terms of socioeconomic status.
This finding is important because it can help identify prognostic factors and better treatment strategies for black Americans with the neurological disease.
To evaluate the clinical features of MS and the role of socioeconomic status among black and white Americans, a team of researchers led by Ellen Mowry, MD, a professor of neurology at Johns Hopkins University, Baltimore, Maryland, compared the MS characteristics between black and white Americans. The team looked at self-reported disability, objective neurologic function assessments, and quantitative brain MRI measurements. They analyzed data from a total of 1214 black Americans and 7530 white Americans with MS.
Brain MRI Measurements
Brain MRI measurements showed that black Americans had more brain lesions and lower overall and gray matter brain volumes compared to white Americans. They also had reduced thalamic, cortical, and deep gray matter volumes.
In terms of self-reported disability, black Americans had a 1.47 times greater odds of severe disability versus mild disability than white Americans.
Socioeconomic Status Adjustments
In white Americans with MS, lower socioeconomic status correlated with worse neuroperformance scores. However, this was not the case for black Americans with MS.
Neurologic Function Assessments
Black Americans performed worse in objective neurologic function assessments compared to white Americans. They obtained lower scores in cognitive processing speed tests (5 points lower on average), walking tests (0.66 seconds slower on average), and manual dexterity tests (2.11 seconds slower on average).
Age, Education Level, and Disability
The researchers found that the black Americans with MS were younger. Moreover, their education level was lower, and they were more likely to have Medicaid insurance or be disabled or unemployed, compared to white Americans with MS.
“While lower socioeconomic status appears to be linked to doing worse on tests of neurologic performance in white people with MS, we do not see that for black people with MS, at least at the single time point we examined,” said Lana Zhovtis Ryerson, MD, one of the authors of the study, in a press release.
Future studies should consider the role of other societal constructs, such as systemic racism, on these findings, according to the authors.
“These results also reinforce the need for more diverse clinical trials and research focusing on treatment strategies specifically for black people to identify whether certain therapies or more aggressive early treatment could help slow down disability over time,” Dr. Ryerson said.
Gray-Roncal K, Fitzgerald K, Ryerson LZ, et al. Association of disease severity and socioeconomic status in black and white Americans with multiple sclerosis. Neurology. Published online July 13, 2021. doi:10.1212/WNL.0000000000012362
Does socioeconomic status explain why Black people with MS have more disability? News Release. American Academy of Neurology; June 30, 2021.