Incidence of multiple sclerosis among First Nations people in Alberta, Canada.

Multiple sclerosis (MS) is thought to be rare among North American aboriginals, although few population-based frequency studies have been conducted. Data from government health databases were used to describe the incidence of MS among First Nations aboriginal people in the province of Alberta compared to the general population from 1994 to 2002. The general population rates were consistently higher than First Nations rates, but were essentially stable across this time span for both groups. For First Nations the MS incidence was 7.6 per 100,000 and 20.6 per 100,000 for the general population in 2002. During 2000-2002 for First Nations the incidence was 12.7 for females and 7.6 for males, with a female-to-male ratio of 1.7:1. During the same period the general population incidence was 32.2 for females and 12.7 for males, with a female-to-male ratio of 2.5:1. The peak incidence for both First Nations and the general population of Alberta was in the age group 30-39 years in 2002. The high incidence rates are consistent with high prevalence rates reported for both groups in 2002: 99.9 per 100,000 for First Nations and 335.0 per 100,000 for the general population. While the MS incidence in First Nations people is lower than in the general population of Alberta, it is not rare by worldwide standards.