Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=221104
Story Retrieval Date: 12/18/2014 2:59:24 PM CST
American Academy of Neurology
The graph shows that African-Americans, especially women, are at a higher risk for developing multiple sclerosis than Caucasians. Other minorities like Hispanics and Asians are at a lower risk than the white population.
Belief that blacks are less likely to develop MS than whites is wrong, study finds
African-Americans have a higher rather than lower risk of developing multiple sclerosis than Caucasians, according to a new study released Tuesday in the medical journal of the American Academy of Neurology.
“Hopefully, this will improve the accuracy of diagnosis in the African-American and Hispanic [communities]," said lead researcher Annette Langer-Gould, MD, a member of the American Academy of Neurology.
For Charmaine Cothran, who was diagnosed with MS in 1998, the process of identifying the illness was not easy.
“This reality can give doctors something to look for instead of being dumbfounded when diagnosing clients,” Cothran said, referring to the study.
Research discovered that not only did African-Americans have a higher risk than before, but that the risk was 47 percent higher compared with Caucasians. Data from other minority groups were not comparable: Hispanics had a 58 percent lower risk while Asians has an 80 percent lower risk than Caucasians.
The 47 percent disparity surprised Cothran, who works at the African-Americans Living With MS Support Group at the Maple Park United Methodist Church in Chicago
“I’m not sure those statistics are correct,” Cothran said. “There are more white people with MS.”
The study further explored the incidence of the disease between sexes. The occurance of MS is skewed toward women across demographics, Langer-Gould said. But the study found that African-American women were three times as likely to develop the debilitating disease than the men in the community.
“It’s just even more pronounced in the African-American population,” Langer-Gould said.
While black men have a higher incidence than previously thought, it's the women who drive the 47 percent overall increased risk, Langer-Gould said. In men, the risk was the almost the same regardless of whether they were black or white. For Hispanics and Asians, both sexes were at a lower risk than their white counterparts.
The study corrects the assumptions drawn from previous studies, which Langer-Gould said were problematic in their methodology and conclusions.
A 1950s study conducted on Korean War veterans evaluated how they accessed service-related benefits at the time. According to this study, white veterans were twice as likely to access the benefits than their black counterparts. Not only was this flawed because MS is more prevalent in women, but ability to access these benefits in the 50s was skewed toward the white population, Langer-Gould said, adding that the situation could have changed since then.
The second study was an “ecological study” that compared incidence of MS in Sweden to the African continent. These are the weakest kinds of studies, said Langer-Gould, adding that a “detection bias” could easily tilt the findings of this study.
“In terms of research, it’s a cautionary tale that we should be a little more circumspect about looking at the strength of the evidence before we start assuming things are true,” said Langer-Gould, who works with Kaiser Permanente Southern California Department of Research & Evaluation in Pasadena, Calif.
This new study, which examined a sample of 3.5 million people, now provides a new direction for further research.
“This is a descriptive study that tells us who gets it, now the question is why,” Langer-Gould said.
One of the popular hypotheses about the causal factors of MS is the role of Vitamin D. Although the level of Vitamin D may explain the high likelihood that African-Americans are developing the condition, it doesn’t explain why Hispanics and Asians have such low probabilities, Langer-Gould said.
She and other colleagues are hoping to get some definitive answers through an “MS sunshine study.” Through this research, they intend to examine exposure to sunshine, resulting levels of Vitamin D in conjunction with other environmental and physiological factors across various demographics.
Langer-Gould added that including minorities in the research will help address the present questions in a more comprehensive manner.
“I think it’s also a really rich learning opportunity that …, including African-Americans and Hispanics in larger MS studies is likely to lead important insights into what causes MS in the first place,” she said.
The National Multiple Sclerosis Society said in a statement that these findings may help them better address the needs of people suffering from this ailment.
“Understanding more about why such differences in MS risk exist may provide clues that will help us end MS forever,” said Timothy Coetzee, Ph.D., chief research officer of the Society.