The Prevalence of Familial Multiple Sclerosis in Saskatoon, Saskatchewan

Abstract

Background. A population-based prevalent cohort of 150 clinical definite multiple sclerosis (MS) cases (102 women; 48 men) ascertained on January 1, 1977, Saskatoon, Saskatchewan, was found to have a familial rate of MS as 17.3%. Objectives. To determine the occurrence of familial MS cases and the frequency of MS among the biological relatives of the study cohort. Methods. The search for new familial cases MS affected relatives continued for 35 years until 2012. The natural history of the disease of sporadic cases is compared with that of the familial cases. SPSS V19 and Kaplan-Meier survival analysis were used for data analysis. Results. Of the 150 unrelated MS patients, 49 cases (32.7%) (36 women and 13 men) were reported of having at least one family member with MS. There were a total of 86 affected relatives, 26 (30.2%) first-degree relatives, 15 (17.4%) second-degree relatives, 20 (23.3%) third-degree relatives, and 25 (29.1%) distant relatives. The average age of MS onset for men with sporadic MS was 33.9 (SD = 10) years and 27.6 (SD = 8.4) years for familial cases and 29.3 (SD = 8.3) years and 26.8 (SD = 8.5) years for women. Conclusion. This 35-year longitudinal natural history study reveals a high frequency of cases with family members developing MS and supports a genetic influence in the etiology of MS.

Genes and Environment in Multiple Sclerosis project: A platform to investigate multiple sclerosis risk

“…While the prevalence of MS in first-degree family members has been documented in different populations 44-46 , the incidence of MS in family members has not been estimated. This information is critical to the design of prospective studies of individuals at risk of MS, and the GEMS study provides the opportunity to assess the incidence rate of MS among first-degree family members.…”

Multiple sclerosis genetics

“…In addition, MS is still less common in both native Japanese and Japanese Americans (5 per 100 000) compared to northern European populations (100-150 per 100 000) (Detels et al, 1977). Similarly, in both the United States and Canada, MS has been reported to be relatively less common among Native Americans (Oger et al, 1975;Kurtzke et al, 1979;Hader, 1982;Svenson et al, 1994). These observed racial patterns of variation in MS prevalence lead to the hypothesis that certain genetic traits may be enriched in populations that are at higher risk for MS and that the same traits may be underrepresented in populations at lower risk for MS.…”

The global prevalence of familial multiple sclerosis: an updated systematic review and meta-analysis

“…The polled prevalence of FMS was estimated to be 11.8% (95% CI: 10.7-13) of the total MS population (Figure 2). The highest and lowest prevalence was found in Saskatchewan of Canada (32.7%) [36] and Hungary (2.2%) [49], respectively. The sensitivity analysis indicated our robust pooled estimate (Figure 3).…”