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Published on: December 9, 2015
Register-based incidence of multiple sclerosis in Brittany (north-western France), 2000-2001
1Department of Epidemiology and Public Health, University Hospital, Rennes, France; CIC-P 0203 Inserm, University Hospital, Rennes, France; West Neuroscience Network of Excellence (WENNE), Brittany, France.
Objectives:
To report on multiple sclerosis (MS) incidence in Brittany, north-western France.
Materials & Methods:
From 2000, we set up a population-based register for patients presenting a putative incident MS (PIMS), that is first symptoms compatible with MS onset. We used 3 medical sources of case ascertainment (neurologists, CSF, regional MS-Clinic). Eligibility criteria required both clinical onset and being permanent resident of Brittany in 2000 or 2001. From 2010, all medical records were tracked, the 10-year follow-up allowing previously reported data to be updated.
Results:
Of 313 eligible PIMS, there were 208 definite MS (both McDonald and Poser criteria), 41 CIS-probable MS (Poser criteria), 32 CIS-possible MS and 32 non-MS. Our incident cohort of 249 MS cases with definite/probable MS (sex ratio 2.95) gave a crude annual incidence of 4.28 per 100,000 inhabitants (6.22 for women, 2.23 for men), and age-standardized rates (adjustment to the European population) of 4.41 [3.32-5.51], 6.68 [4.75-8.60], and 2.21 [1.12-3.31], respectively. Age-specific rates by gender and initial course showed that attack onset MS peaked at 25-29 years and progressive onset MS at 40-44 years in women (20-24 years and 45-49 years in men, respectively).
Conclusions:
Brittany is confirmed a high-risk region for MS. Our data show marked differences in sex-specific pattern of MS incidence by clinical course and point out 25- to 29-year-old women as having the highest MS risk. While temporal variations cannot be excluded, comparison with overall French data suggests that other factors rather than latitude may influence the MS risk in France.
Insights
Brittany, France, has a high incidence of multiple sclerosis (MS). Women aged 25-29 years face the highest risk, with incidence rates varying by clinical course and gender.
Area of Science:
- Neurology
- Epidemiology
Background:
- Multiple sclerosis (MS) is a chronic neurological disease with a complex etiology.
- Geographic variations in MS incidence suggest environmental or genetic influences.
Purpose of the Study:
- To determine the incidence of multiple sclerosis (MS) in Brittany, a region in north-western France.
- To analyze MS incidence patterns based on sex, age, and clinical course.
Main Methods:
- A population-based MS register was established in Brittany from 2000.
- Case ascertainment utilized multiple medical sources, including neurologists, cerebrospinal fluid (CSF) analysis, and regional MS clinics.
- Eligibility criteria included clinical onset and residency in Brittany during 2000-2001, with 10-year follow-up data.
Main Results:
- A cohort of 249 definite or probable MS cases was identified.
- The crude annual incidence of MS was 4.28 per 100,000 inhabitants (6.22 in women, 2.23 in men).
- Age-specific incidence peaked at 25-29 years for women with attack-onset MS and 40-44 years for progressive MS; men showed peaks at 20-24 and 45-49 years, respectively.
Conclusions:
- Brittany is confirmed as a high-risk area for multiple sclerosis.
- Significant sex-specific differences in MS incidence were observed, particularly by clinical course.
- Young women (25-29 years) exhibit the highest MS risk; factors beyond latitude may influence MS risk in France.
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