“Our findings suggest that there has been a steady rise in the prevalence of MS over the past 5 decades, that the prevalence of MS remains higher for women than men, and that a north-south geographic gradient still persists,” wrote lead author, of Georgetown University, Washington, and his coauthors. The study was published in .
To determine adult cases of MS, Dr. Wallin and colleagues applied a validated algorithm to private, military, and public AHC datasets. Data from the 2010 U.S. Census were also used to standardize age and sex. In total, 125 million people over 18 years of age were captured in the study, nearly 45% of the U.S. population.
After adjustment, the 2010 prevalence for MS cumulated over 10 years was 309.2 per 100,000 adults (95% confidence interval, 308.1-310.1). This represented a total of 727,344 people with MS. The female to male ratio was 2.8, with a prevalence of 450.1 per 100,000 (95% CI, 448.1-451.6) for women versus a prevalence of 159.7 (95% CI, 158.7-160.6) for men. The age group with the highest estimated prevalence was 55-64 years old, and the prevalence in northern regions of the United States was statistically significantly higher than in southern regions.
The limitations of this study included not including children, the Indian Health Service, the U.S. prison system, or undocumented U.S. residents in the prevalence estimates. However, the authors did note that “these segments of the population are relatively small or, in the case of children, would contribute few cases.” In addition, they were unable to acquire more than 3 years of data for all insurance pools because of high costs.
The study was funded by a grant from the National Multiple Sclerosis Society. The authors reported numerous disclosures, including receiving consulting fees, researching funding, and grant support from various government agencies, foundations, and pharmaceutical companies.
SOURCE: Wallin MT et al. Neurology. 2019 Feb 15. .