Background:
The Canadian Chronic Disease Surveillance System (CCDSS), supported by the Public Health Agency of Canada (PHAC), collects administrative data from every province and territory to generate national estimates on the prevalence and incidence of chronic diseases, including multiple sclerosis (MS). The administrative data collected covers approximately 97% of the Canadian population.
PHAC released the incidence and prevalence rates of MS in Canada from data that was collected between 2014 and 2015.
How the CCDSS monitors MS?
To estimate the incidence and prevalence rates of MS in Canada, PHAC used an algorithmic approach identified by Widdifield and colleagues. Following a series of analyses of health care databases, it was found that the most accurate data on MS cases in Canada were achieved through the following combination of administrative data: residents covered by public health insurance and with one hospitalization or five physician billing records over two years.
MS Incidence and Prevalence Rates in Canada
Using the methodology described above, the new 2014-2015 data on adults (20+ years old) diagnosed with MS estimates that over 77,000 Canadian adults are living with MS. This equates to 2.6 individuals per 1,000 adult population or an estimated 1 in every 385 Canadians. Other estimates include:
- Women are three times more likely to be diagnosed with MS than men
- On average, 11 Canadians are diagnosed with MS every day
- 60% of adults diagnosed with MS are between the ages of 20 and 49 years old.
Since the first estimates reported in 2003-2004 by the CCDSS to the most recent rates from 2014-2015, the proportion of Canadians living with MS has continuously increased.
Why are these numbers different than those previously reported?
In 2014, the MS Society reported that an estimated 100,000 Canadians were living MS. This data was reported based on several surveys that were developed through the National Population Health Study of Neurological Conditions to estimate the incidence and prevalence rates of MS in households and long-term care facilities. One of the surveys, the 2010-2011 Canadian Community Health Survey (CCHS), asked respondents if they, or members of their household had any one of 18 neurological conditions including MS. With this type of questionnaire, it is possible households over-reported MS (e.g. not diagnosed with MS but going through tests for potential MS). In comparison, CCDSS identified the incidence and prevalence rates of MS using validated data from health care visits, allowing the CCDSS to utilize a more reliable method to determine the national estimates of MS in the adult Canadian population.
Comment:
National estimates of Canadians living with MS will help inform government officials and policymakers to develop campaigns and initiatives that will provide access to treatment and care as well as influence policy change at the federal level. Furthermore, they will raise awareness amongst, and increase communications to, stakeholders about the impact of MS in Canada. These new, up-to-datestatistics in MS will help guide the MS Society in developing and implementing programs and services, government relations efforts and further accelerate MS research priorities in alignment with our mission to improve the quality of lives, and ultimately, find a cure for people living with MS.
Resources:
Widdifield J et al. (2015) Development and validation of an administrative data algorithm to estimate the disease burden and epidemiology of multiple sclerosis in Ontario, Canada. Mult Scler. 21 (8): 1045-54.
Canadian Chronic Disease Surveillance System 2000/2001-2013-2014
Canadian Chronic Disease Surveillance System Public Health Infobase