Background The Multiple Sclerosis International Federation (MSIF) Atlas of MS is the most extensive worldwide study of the epidemiology and initial clinical features of MS and the global availability and accessibility of resources for people with MS. Findings from the 2008 and 2013 editions have been widely cited by the global MS research, advocacy, and policy communities.
Objectives This analysis aims to provide a greater understanding of the epidemiology of MS worldwide. Valid data regarding the global distribution of MS and characteristics of disease presentation will enhance research and enable decision makers to improve healthcare policy and allocate resources to better meet the needs of people with MS, their caregivers, and families.
Methods Between September 2019 and March 2020, country coordinators completed a questionnaire to report the most recent epidemiologic data available about MS in their country. The questionnaire was available in multiple formats and languages (i.e., English, French, and Spanish). Survey questions included country-specific prevalence and incidence rates (overall, by sex, and pediatric), mean age of MS onset, disease course (at presentation and currently), and type of clinical criteria used for MS diagnosis.
Results Data were gathered from 115 countries, accounting for 87% of the world population. The incidence rate among countries reporting this data (n=75) was 2.1 per 100,000 persons per year (0.01-33). Incidence rates were highest in the European region (6.8) and lowest amongst the African (0.4) and South-East Asian regions (0.4). The average age of MS diagnosis was 32 years. At the time of diagnosis, on average, 85% of individuals had relapsing-remitting MS. Females represented sixty-nine percent of all MS cases.
Conclusions The Atlas of MS provides a comprehensive look at the epidemiologic data of MS around the world. While the rate of MS cases varies by region, patient characteristics are similar. Little variation is seen between countries regarding mean age of MS onset and percentage of patients with relapsing- remitting MS.