Kaiser Researchers Link MS To Race
Researchers have used data from Kaiser Permanente's Southern California health plan enrollees to establish a higher rate of multiple sclerosis among African American women than compared to caucasians.
The data, which was published in the most recent issue of the academic journal Neurology, questions prior assumptions that African Americans were less likely to contract the degenerative nerve disease than caucasians.
That assumption has been held for more than 50 years, and can be traced back to a study of service personnel who served in the Korean War. It had discovered that white veterans were twice as likely to receive disability benefits for MS than African American males.
That study did not control for the institutional segregation that was common in the U.S. during that era, and the possibility that African Americans may have been passively or even actively discouraged from filing for benefits.
This new study focused instead not on benefit applications, but the medical records of more than 3.5 million Kaiser enrollees in Southern California compiled between January 2008 and December 2011. A total of 496 patients were recently diagnosed with MS.
Among those cases, African American patients were 47% more likely to have contracted the disease than caucasians, although the prevalence of MS was roughly equal between black and white males.
The study concluded that overall women are 70% more likely to contract the disease than men, with much of the differential between African Americans and caucasians pegged to female patients specifically.
“Although additional research is needed, possible explanations for the higher incidence of MS in black women include a greater prevalence of hormonal, genetic,
r environmental risk factors such as smoking, compared to patients from other racial or ethnic groups," said study lead author Annette Langer-Gould, M.D., of Kaiser's research and evaluation arm. "Our findings do not support the widely held belief that blacks have a lower risk of MS than whites, but that MS risk is determined by complex interactions between race, ethnicity, sex, environmental factors and genotypes."
Extrapolating the study's data, Kaiser researchers estimated that 19,000 people per year in the U.S. are newly diagnosed with MS each year. There are about 350,000 Americans currently living with the condition, according to the Multiple Sclerosis National Research Institute.
The Kaiser study identified the average age of MS diagnosis as 41.6 years, but found its onset occurred anywhere between 8.6 and 78.3 years. The study also found the median time from symptom onset to MS diagnosis was four months, but could be as long as 40 years. Additonally, Latino and Asian patients were generally younger at the time of MS diagnosis than white and black patients.
