Incidence and Prevalence of Multiple Sclerosis in Malmö, Southern Sweden

Lucía Alonso-Magdalena; Elisabet Zia; Olga Carmona I Codina; Hélène Pessah-Rasmussen; Peter Sundström

doi:10.1155/2022/5464370

Incidence and Prevalence of Multiple Sclerosis in Malmö, Southern Sweden

Mult Scler Int. 2022 Mar 19:2022:5464370. doi: 10.1155/2022/5464370. eCollection 2022.

Authors

Lucía Alonso-Magdalena¹, Elisabet Zia², Olga Carmona I Codina³, Hélène Pessah-Rasmussen⁴, Peter Sundström⁵

Affiliations

¹ Department of Neurology, Skåne University Hospital and Department of Clinical Sciences, Lund University, Lund, Sweden.
² Department of Clinical Sciences, Lund University, Malmö, Sweden.
³ Department of Neurology, Fundacio Salut Emporda, Figueres and Department of Clinical Sciences, Faculty of Medicine, Girona University, Spain.
⁴ Department of Rehabilitation medicine, Skåne University Hospital and Department of Clinical Sciences, Lund University, Lund, Sweden.
⁵ Department of Clinical Science, Neurosciences, Umeå University, Umeå, Sweden.

Abstract

Objectives: To estimate the incidence and prevalence of multiple sclerosis (MS) in Malmö municipality in southwestern Sweden.

Materials and methods: Multiple sources were used in the case identification process. Case ascertainment was assessed by medical chart review including examinations such as magnetic resonance imaging, cerebrospinal fluid analyses, and relevant laboratory tests. Cases were classified according to the 2010 McDonald's diagnostic criteria. Onset-adjusted prevalence and a definition of onset symptoms were applied.

Results: The crude incidence of MS in 2001-2010 in Malmö municipality was 5.3/100,000 (95% confidence interval (CI): 4.5 to 6.2). There was a relapsing onset in 90.5% of cases. The female to male ratio was 1.8. The onset-adjusted prevalence for Dec 2010 was 133/100,000 (95% CI, 120 to 146) with a female to male ratio of 2.1.

Conclusions: This is the first population-based epidemiological study in Skåne, the most southwestern part of Sweden showing a high incidence and prevalence. We found a lower incidence than expected according to previous nationwide figures, probably due to methodological differences between the studies. Our findings support the presence of a north-south gradient of MS prevalence in Sweden.