DALLAS – The way Lilyana Amezcua, MD, sees it, researchers should look beyond using race and ethnicity only as demographic variables when reporting results from multiple sclerosis studies.
Doug Brunk/MDedge News
Dr. Lilyana Amezcua
“As a demographic variable we see it all the time: white versus non-white, and the methods to arrive at a category are seldom discussed,” Dr. Amezcua said at a meeting of the Americas Committee for Treatment and Research in Multiple Sclerosis. “We need to think about ethnocentric research, where the method for determination for race and ethnicity becomes important. This includes examining self-identity (ethnicity), along with physical characteristics and medical records, and confirming that beyond the individual.”
The goal, she continued, is to identify who is at risk for inferior health, such as trying to sort out biological and genetic explanations from non-biological explanations. Ethnocentric research also helps to address health care disparities. “But there’s a broad intersection between race and ethnicity, and depending on the question, genetic ancestry could help,” said Dr. Amezcua, a neurologist at the Keck School of Medicine at the University of Southern California, Los Angeles. “Race tries to infer biological differences, ethnicity infers societal differences, and ancestry infers genetic variations.”
While genetic and biologic features are often used to evaluate how race and ethnicity affects those with MS, Dr. Amezcua noted that several additional factors could influence outcomes. These include access to care as well as individual and community factors that relate to social determinants of health, such as poverty, exposures, and environmental stress. “These could be contributing to worse outcomes,” she said. “So could modifiable factors such as illness beliefs, health literacy, illness management, and acculturation.”
In terms of health literacy, there are reports suggesting that there is a general lack of adequate education and understanding about MS treatment and realistic expectations in African Americans and Hispanics, she said.
In addition, research has shown there is a lower probability of being under the care of a neurologist if you lack health insurance (odds ratio = 0.38) or are African American (OR = 0.52) or Hispanic (OR = 0.61), based on nationally representative data from the 2006-2013 Medical Expenditure Panel Survey (Neurology. 2017;88[24]:2268-75). “Just being African American or Hispanic lowered the probability of seeing a neurologist,” she said.
Published evidence also exists to suggest that illness beliefs drive some people away from MS treatment. “These are beliefs embedded in social and cultural factors known as cultural idioms,” Dr. Amezcua explained. “In a study that was able to capture qualitative and quantitative data, researchers found that social and cultural factors were more frequently reported in immigrant groups, alluding to the fact that we need to look beyond whether they are African American or Hispanic, and look at acculturation” (Int J MS Care. 2017;19[3]:131-9).
Then there’s the issue of Food and Drug Administration-approved disease-modifying therapies in MS and minorities. In an exploratory post hoc analysis of the Evidence of Interferon Dose-Response: European North American Comparative Efficacy (EVIDENCE) study, researchers found that African-American subjects experienced more exacerbations and were less likely to remain exacerbation free, compared with whites (Arch Neurol. 2005;62[11]:1681-3). The African-American subjects also developed more new MS lesions on T2-weighted brain MRI at 48 weeks (P = .04).
“There are a lot of unanswered questions, but understanding the effect of race/ethnicity is crucial to understanding MS disparities,” Dr. Amezcua said. “To better understand genetic variation in the context of health disparities, using ‘genetic ancestry’ could help with precision medicine. We must remember that minorities with MS face barriers related to access and education in MS care much more so than whites.”
She concluded her remarks by underscoring the importance of increasing minority participation in research and clinical trials. “But today, clinical trial participation by minorities is less than 10%. As we progress, and as we get closer to precision medicine, the health disparities will widen.”
She reported having no financial disclosures.