Disease Severity and Socioeconomic Status in Black and White Patients with Multiple Sclerosis

Previous reports have suggested that black patients with multiple sclerosis (MS) have a greater disability than white patients. Many of these studies had small sample sizes or used semiquantitative measures of disability. In addition, the interaction of socioeconomic status and race have not been well-studied. To understand the burden of disease in black patients and white patients and the role of socioeconomic status, the investigators conducted a cross-sectional study of patients from 7 MS centers in the United States.

The investigators obtained the data for their analysis from the Multiple Sclerosis Partners Advancing Technology Health Solutions network. Biogen, Inc, sponsors the network but did not fund this study. Clinics in the network collect standardized data on physical performance, cognitive processing speed, clinical outcomes, and sociodemographic information at routine visits. Brain magnetic resonance imaging scans were taken for a subset of patients.

Of 8744 patients in the analysis, 14% self-identified as black and 86% self-identified as white. Compared with white patients, black patients were younger, had a lower education level, and were less likely to have private insurance. Self-reported disability was significantly greater in black patients compared with white patients. Black patients were also more likely to be taking higher-efficacy medication.

The investigators analyzed clinical outcomes after adjustment for covariates. Black patients had worse neuroperformance outcomes for walking speed, manual dexterity, and cognitive performance.

Analysis of disease burden in the brain also suggested greater disease severity in black patients. Compared with white patients, black patients had greater total T2 lesion volume. Unlike in healthy people, overall brain volume and gray matter volume were lower in black patients compared with white patients.

The investigators carried out multivariate analysis using measures of socioeconomic status based on address using data for the subset of patients treated at the Johns Hopkins site of the network. Lower socioeconomic status was associated with poorer neuroperformance for white patients. For black patients, there did not appear to be an association between neuroperformance and socioeconomic status.

The results suggested that black patients with MS have greater disease severity than white patients, even after adjusting for socioeconomic differences. Because the study was a cross-sectional design, the investigators could not exclude the possibility of confounding they could not measure. “Representative cohort studies that longitudinally assess comorbidity or comorbidity management, MS disease activity, and MS therapy use, along with indications for that use of therapy to account for confounding by indication, are needed,” they suggested.

Furthermore, the investigators said, “The results also reinforce the need for more racially representative phase 3 clinical trials and comparative-effectiveness research focusing on treatment strategies specifically in the Black American population to identify whether, for example, certain therapies or more aggressive early treatment will better mitigate long-term disability accrual.”

Source

Gray-Roncal K, Fitzgerald KC, Ryerson LZ, et al. Association of disease severity and socioeconomic status in black and white Americans with multiple sclerosis. Neurology. 2021;97:e881-e889.