Challenging Prevailing Beliefs: Greater Incidence of Multiple Sclerosis in Black Americans Than Anticipated

The frequency of Multiple Sclerosis (MS) in Black Americans is found to be greater than previously assumed, highlighting the urgent need for more equal access to preventive measures and treatments, reports the University of Maryland School of Medicine.

The same researchers also unveiled that MS is more widespread in the northern regions of the U.S.

Historically, multiple sclerosis has been identified as a condition majorly affecting people of European descent, especially those of white ethnicity. A new research by the University of Maryland School of Medicine (UMSOM), however, presents a different viewpoint.

Their study reveals that this debilitating neurological disorder is actually more prevalent among Black Americans than previously understood. Moreover, the research shows a notably higher occurrence of the disease in the northern U.S, including regions like New England, the Dakotas, and the Pacific Northwest.

These recent findings have been published in the renowned JAMA Neurology journal.

“Our research showed a significantly higher prevalence of multiple sclerosis in Black Americans than previously known,” said the study’s corresponding author Mitchell Wallin, MD, MPH, Associate Professor of Neurology at UMSOM. “This underscores the severe impact of healthcare disparities and lack of diversity in clinical research, which have contributed to misconceptions about disease prevalence in historically underserved and underrepresented populations.”

Multiple sclerosis triggers the immune system to attack the central nervous system, specifically the protective myelin layer that covers nerve fibers. Symptoms can include numbness, mood swings, memory issues, pain, fatigue, and in extreme cases, paralysis or blindness. In 2019, Dr. Wallin led a team that discovered the prevalence of MS in the U.S. to be nearly 1 million people, doubling the previously estimated figures.

In their recent study, Dr. Wallin and his team evaluated de-identified health insurance claims from three years, comprising 96 million adults, to identify individuals living with MS. They further estimated the number of adults aged 18 or older living with MS in different states and the prevalence of MS among individuals of different races or ethnicities living in particular regions.

The research yielded substantial evidence of a higher prevalence of MS in the U.S.’s northern regions compared to the south. “The reason behind this pattern is still uncertain. However, it could be related to virus spread in colder climates where people stay indoors more, or lower vitamin D levels due to less sun exposure,” said Dr. Wallin.

Several observational studies have associated low vitamin D levels with a heightened risk of MS and progressive disease. Other pivotal research published in Science discovered that Epstein-Barr virus infection significantly increases MS risk, with recent research showing that antibodies generated against the virus attack a critical protein in the brain and spinal cord.

Regarding MS prevalence in specific American sub-groups, the researchers found the highest prevalence in white people, followed by Black people, “other races,” and people of Hispanic/Latinx ethnicity. MS is found in approximately 4 in 1,000 white people, about 3 in 1,000 Black people, around 2 in 1,000 people of “other races,” and roughly 1.5 in 1,000 people of Hispanic/Latinx origin.

“These findings could have a significant impact on public policymakers, aiding them to allocate resources more fairly towards populations that have been historically overlooked in MS research, and underserved in prevention efforts and treatment options,” said UMSOM Dean Mark T. Gladwin, MD, Vice President for Medical Affairs, University of Maryland, Baltimore, and the John Z. and Akiko K. Bowers Distinguished Professor. “Given the diverse patient base we serve across Maryland and in Baltimore, we have a unique opportunity through the new UM Institute for Health Computing to introduce new MS treatment advances to eligible African American patients.”

Reference: “Population-Based Estimates for the Prevalence of Multiple Sclerosis in the United States by Race, Ethnicity, Age, Sex, and Geographic Region” by Michael Hittle, William J. Culpepper, Annette Langer-Gould, Ruth Ann Marrie, Gary R. Cutter, Wendy E. Kaye, Laurie Wagner, Barbara Topol, Nicholas G. LaRocca, Lorene M. Nelson, and Mitchell T. Wallin, 15 May 2023, JAMA Neurology.
DOI: 10.1001/jamaneurol.2023.1135

The National Multiple Sclerosis Society funded the study.

Frequently Asked Questions (FAQs) about Multiple Sclerosis Prevalence in Black Americans

More about Multiple Sclerosis Prevalence in Black Americans

• University of Maryland School of Medicine
• JAMA Neurology Journal
• National Multiple Sclerosis Society
• Multiple Sclerosis – Symptoms and Causes
• Epstein-Barr Virus Infection and Multiple Sclerosis