The prevalence of multiple sclerosis (MS), a risk factor for severe neurologic disability, has substantially increased since 1990, according to study results published in Lancet Neurology.
The epidemiology of MS between 1990 and 2016 was assessed in the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) with outcomes for MS modeled with DisMod-MR version 2.1.
A total of 13,110 site-years of vita registration data in the GBD’s cause of death ensemble modeling module was used to evaluation MS as the cause of death. Disability-adjusted life-years (DALYs) provided data on prevalence and deaths, calculated as the total of years of life lost (YLLs), as well as years of life lived with a disability.
Since 1990, there has been a 10.4% (95% uncertainty interval [UI], 9.1-11.8) increase in the age-standardized prevalence of MS worldwide, corresponding to 2,221,188 prevalent MS cases (95% UI, 2,033,866-2,436,858) in 2016.
Regions with the highest age-standardized MS prevalence estimates per 100,000 population included high-income North America (164.6; 95% UI, 153.2-177.1), Western Europe (127.0; 95% UI, 115.4-139.6), and Australasia (91.1; 95% UI, 81.5-101.7).
Conversely, the regions with the lowest MS prevalence estimates were eastern sub-Saharan Africa (3.3; 95% UI, 2.9-3.8), central sub-Saharan African (2.8; 95% UI, 2.4-3.1), and Oceania (2.0; 95% UI, 1.71-2.29).
A total of 18,932 (95% UI, 16,577-21,033) deaths due to MS were observed in 2016. The number of DALYs in 2016 reached 1,151,478 (95% UI, 968,605-1,345,776). Age-standardized death rates decreased worldwide during the studied period (change, –11.5%; 95% UI, –35.4 to –4.7). The effect on YLLs due to premature death and disability was greatest in the sixth decade of life (22.05; 95% UI, 19.08-25.34).
Changes in age-standardized DALYs assessed with the Socio-demographic Index, which is comprised of income per person, years of education, and fertility data, were variable.
The lack of robust predictive covariates for MS, as well as absent data for other geographic regions, represent a couple of limitations associated with the GBD.
According to the researchers, the findings from their analysis “will be useful for resource allocation and health services planning for the growing numbers of patients with multiple sclerosis in ageing societies.”
GBD 2016 Multiple Sclerosis Collaborators. Global, regional, and national burden of multiple sclerosis 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet Neurol. 2019;18(3):269-285.