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Published on: December 9, 2015
Incidence and prevalence of multiple sclerosis in Newfoundland and Labrador
J S Sloka1, W E M Pryse-Phillips, M Stefanelli
1Faculty of Medicine (Neurology), Memorial University of Newfoundland, St. John's, NL, Canada. p97jss@mun.ca
Background:
The incidence and prevalence of multiple sclerosis (MS) in Newfoundland and Labrador (NL) had been reported in 1984 and was considered to be relatively low at that time. This study revisits the incidence and prevalence of MS in NL for the year 2001.
Methods:
Case searches through patient files of neurologists in NL were conducted. A complete list of patients billed for MS in NL between 1996 and 2003 was obtained and all cases were confirmed via chart review.
Results:
There were 493 living MS patients yielding a prevalence of 94.4/100,000 which is significantly higher than previously reported. Of the living patients, 330 had relapsing remitting (RRMS), 94 had secondary progressive, 66 had primary progressive (PPMS) and three had unspecified MS. The total female to male ratio was 2.7:1. There was no difference between the female to male ratios for RRMS vs PPMS. Patients with PPMS had a later onset compared to RRMS (p<0.00001). Yearly incidences were relatively constant from 1994 to 2001 (5.6/100,000). Significant delays between first symptoms and final diagnosis were common and the delay time has not changed over the past 15 years. A prevalence of 88.9/100,000 was estimated from survival and incidence trends and was not significantly different than the measured prevalence (p=0.38).
Conclusions:
The increase in incidence and prevalence are accounted for through both better access to diagnostic facilities and more practicing neurologists. The revised prevalence and incidence are more in keeping with recently reported values throughout Canada.
Insights
Multiple sclerosis (MS) prevalence in Newfoundland and Labrador has significantly increased since 1984, now aligning with national averages. This rise is linked to improved diagnostic access and more neurologists, though diagnostic delays persist.
Area of Science:
- Neurology
- Epidemiology
Background:
- Previous 1984 study indicated low multiple sclerosis (MS) incidence and prevalence in Newfoundland and Labrador (NL).
- This study aimed to reassess MS epidemiology in NL for the year 2001.
Purpose of the Study:
- To determine the current incidence and prevalence of multiple sclerosis (MS) in Newfoundland and Labrador (NL).
- To compare current MS rates with historical data and national averages.
- To analyze MS subtypes, patient demographics, and diagnostic timelines.
Main Methods:
- Conducted case searches using neurologist patient files in NL.
- Obtained a comprehensive list of patients billed for MS between 1996 and 2003.
- Confirmed all cases through thorough chart review.
Main Results:
- A prevalence of 94.4/100,000 was identified, significantly higher than previously reported.
- The majority of patients had relapsing-remitting MS (RRMS), followed by secondary progressive and primary progressive MS (PPMS).
- Yearly incidence remained constant (5.6/100,000) from 1994-2001, with persistent diagnostic delays.
Conclusions:
- Increased MS incidence and prevalence are attributed to enhanced diagnostic facility access and a greater number of practicing neurologists.
- The updated figures for MS prevalence and incidence in NL are now consistent with recent Canadian data.
- Despite improved diagnosis, significant delays between symptom onset and diagnosis remain unchanged.
