Multiple sclerosis in New Zealand Māori

Area of Science:

• Epidemiology
• Neurology
• Public Health

Background:

• Previous studies indicated significantly lower multiple sclerosis (MS) prevalence in Māori compared to European populations in New Zealand.
• Historical regional surveys (1968-2001) consistently reported minimal or no MS cases among Māori.

Purpose of the Study:

• To determine the current prevalence of MS in New Zealand, stratified by Māori ancestry.
• To investigate if Māori ancestry influences clinical features or geographical distribution of MS.
• To assess the impact of Māori ancestry on MS prognosis.

Main Methods:

• Analysis of MS prevalence data for New Zealand in 2006, including age-standardized rates per 100,000.
• Comparison of prevalence rates between individuals with and without indigenous Māori ancestry.
• Evaluation of clinical features and latitude data in relation to Māori ancestry.

Main Results:

• The overall age-standardized prevalence of MS in New Zealand was 73.2 per 100,000 in 2006.
• Individuals with Māori ancestry had a significantly lower prevalence of 20.6 per 100,000, 3.6 times lower than the general population.
• No differences in clinical MS features or latitudinal distribution were observed between those with and without Māori ancestry.

Conclusions:

• Māori ancestry is not associated with the latitude-dependent increase in MS prevalence observed in New Zealand.
• MS prognosis appears to be independent of Māori ancestry.
• There is an indication that MS prevalence may be increasing within the Māori population.