Multiple sclerosis prevalence in 2000 and 2010 in Western Finland

Objective: To study ten-year change in MS prevalence in the Province of Western Finland in Tampere University Hospital District located in 62.7°N, 23.7°E. Methods: Age-standardized prevalence/105 by using direct standardization in European Standard Population (ESP2013) and crude prevalence/105 with 95% confidence interval (95% CI) were assessed among resident MS cases fulfilling Poser criteria by sex and disease course in 31.12.2000 and 31.12.2010. MS-related disability and disease-modifying treatment (DMT) use were estimated in 31.12.2010. Results: Crude prevalence increased 49% from 129/105 (95% CI 121-137) in 2000 (N 1080) to 196/105 (187-203) in 2010 (N 1666). Age-standardized prevalence increased 45% from 133/105 (127-140) to 192/105 (184-200) and peaked in 40- to 49-year age-group. Age-standardized prevalence increased 58% among women from 176/105 (171-176) to 277/105 (270-284) and 31% among men from 91/105 (87-95) to 119/105 (115-124). Increase in RRMS was 61% from 111/105 (105-117) to 179/105 (171-186), and decrease in PPMS was 14% from 21/105 (19-24) to 18/105 (15-21). In 2010 among the 52% RRMS cases on DMT, MS-related disability was mild in 50%. In total, cohort disability was mild in 46%, moderate to severe in 47%, and information was not available in 14%. Conclusion: A significant increase in prevalence was observed in Western Finland. Increase was higher among women and in relapsing-remitting onset MS. Disability showed age- and disease course-specific variation.