Immigrants to Canada who have spent a greater proportion of their lives in Canada have a greater risk of developing multiple sclerosis (MS) than people who have spent a smaller proportion of their lives there, according to a study published in the April 24, 2024, online issue of Neurology, the medical journal of the American Academy of Neurology. The study on MS risk for immigrants does not prove that an increased proportion of life in Canada causes MS; it only shows an association.

Understanding MS Risk for Immigrants

Immigrants residing in Canada for longer durations face a higher risk of developing multiple sclerosis (MS), according to a recent study published in Neurology. While the study doesn’t establish causation, it highlights a concerning trend.

Factors Behind the Findings

Dr. Manav V. Vyas, the study author, suggests that longer residency may expose immigrants to unhealthy lifestyles prevalent in Canada, potentially elevating MS risk. Lifestyle changes and environmental factors may play pivotal roles.

Research Insights

The study tracked 1.5 million immigrants arriving in Canada between 1985 and 2003, observing their MS incidence until 2016. Results indicate a notable correlation between time spent in Canada and MS risk.

Further Reading: Life Stressors Could Contribute to Multiple Sclerosis Flares, Disability

Quantifying the Risk

Individuals spending 70% of their lives in Canada were 38% more likely to develop MS compared to those spending only 20% of their lives there. This correlation persisted even after adjusting for various factors like age and sex.

Exploring Potential Influences

Researchers speculate on multiple factors driving this trend, including lifestyle changes like increased smoking rates, dietary shifts, sunlight exposure, and even variations in gut microbiome composition.

Considerations and Limitations

While shedding light on the issue, the study acknowledges limitations. Notably, the reliance on healthcare system data may overlook immigrants’ differences in seeking care due to cultural, linguistic, or healthcare system-related factors.


Understanding these findings prompts a call for further research into mitigating MS risk factors among immigrants. This underscores the importance of promoting healthy lifestyles and providing accessible healthcare resources for all residents.

The study was supported by the MS Society of Canada and the Consortium of Multiple Sclerosis Centers.