Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-28T16:09:26.008Z Has data issue: false hasContentIssue false

The Incidence and Prevalence of Multiple Sclerosis in Nova Scotia, Canada

Published online by Cambridge University Press:  23 September 2014

Ruth Ann Marrie*
Affiliation:
Department of Internal Medicine, Department of Community Health Sciences, University of Manitoba, Winnipeg
John D. Fisk
Affiliation:
Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia Department of Medicine, Dalhousie University, Halifax, Nova Scotia
Karen J. Stadnyk
Affiliation:
Capital District Health Authority, Halifax, Nova Scotia
Bo Nancy Yu
Affiliation:
Department of Internal Medicine, Department of Community Health Sciences, University of Manitoba, Winnipeg
Helen Tremlett
Affiliation:
Department of Medicine (Neurology), University of British Columbia, Vancouver, British, Columbia
Christina Wolfson
Affiliation:
Department of Epidemiology and Biostatistics and Occupational Health, Research Institute of the McGill University Health Centre, Montreal, Quebec
Sharon Warren
Affiliation:
Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada
Virender Bhan
Affiliation:
Department of Medicine, Dalhousie University, Halifax, Nova Scotia
*
Health Sciences Center, GF-533, 820 Sherbrook Street, Winnipeg, Manitoba, R3A 1R9, Canada. Email: [email protected].
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.
Background:

Estimates of incidence and prevalence are needed to determine disease risk and to plan for health service needs. Although the province of Nova Scotia, Canada is located in a region considered to have a high prevalence of multiple sclerosis (MS), epidemiologic data are limited.

Objective:

We aimed to validate an administrative case definition for MS and to use this to estimate the incidence and prevalence of MS in Nova Scotia.

Methods:

We used provincial administrative claims data to identify persons with MS. We validated administrative case definitions using the clinical database of the province's only MS Clinic; agreement between data sources was expressed using a kappa statistic. We then applied these definitions to estimate the incidence and prevalence of MS from 1990 to 2010.

Results:

We selected the case definition using ≥7 hospital or physician claims when >3 years of data were available, and ≥3 claims where less data were available. Agreement between data sources was moderate (kappa = 0.56), while the positive predictive value was high (89%). In 2010, the age-standardized prevalence of MS per 100,000 population was 266.9 (95% CI: 257.1- 277.1) and incidence was 5.17 (95% CI: 3.78-6.56) per 100,000 persons/year. From 1990-2010 the prevalence of MS rose steadily but incidence remained stable.

Conclusions:

Administrative data provide a valid and readily available means of estimating MS incidence and prevalence. MS prevalence in Nova Scotia is among the highest in the world, similar to recent prevalence estimates elsewhere in Canada.

Résumé

RÉSUMÉ Contexte:

Des estimés de l'incidence et de la prévalence sont nécessaires pour établir le risque d'une maladie et pour la planification des services de santé. Bien que la province de Nouvelle-Écosse au Canada soit située dans une région considérée comme à haute prévalence de sclérose en plaques (SP), il existe peu de données épidémiologiques à ce sujet.

Objectif:

Le but de l'étude était de valider une définition administrative de cas pour la SP et de l'utiliser pour estimer l'incidence et la prévalence de la SP en Nouvelle-Écosse.

Méthode:

nous avons utilisé des données administratives provinciales de réclamation pour identifier les individus atteints de la SP. Nous avons validé les définitions administratives de cas au moyen de la base de données cliniques de la seule clinique de SP de cette province. La concordance entre les sources de données a été évaluée au moyen du test de concordance Kappa. Nous avons ensuite appliqué ces définitions pour estimer l'incidence et la prévalence de la SP de 1990 à 2010.

Résultats:

Nous avons choisi la définition de cas au moyen de 7 réclamations ou plus provenant d'un hôpital ou d'un médecin quand des données couvrant une période de plus de 3 ans étaient disponibles et 3 réclamations ou plus quand moins de données étaient disponibles. La concordance entre les sources de données était modérée (kappa = 0,56) et la valeur prédictive positive était élevée (89%). En 2010, la prévalence de la SP ajustée pour l'âge par 100 000 de population était de 266,9 (IC à 95% : 257,1 à 177,1) et l'incidence était de 5,17 (IC à 95% : 3,78 à 6,56) par 100 000 de population par année. De 1990 à 2010, la prévalence de la SP a augmenté régulièrement mais son incidence est demeurée stable.

Conclusions:

Les données administratives fournissent des moyens valides et facilement disponibles d'estimer l'incidence et la prévalence de la SP. La prévalence de la SP en Nouvelle-Écosse est l'une des plus élevées dans le monde et elle est comparable à celle des autres régions du Canada.

Type
Original Article
Copyright
Copyright © The Canadian Journal of Neurological 2013

References

1. Evans, C, Beland, S, Kulaga, S, et al. Incidence and prevalence of multiple sclerosis in the Americas: a systematic review. Neuroepidemiology. 2013;40(3):195210.CrossRefGoogle ScholarPubMed
2. Allison, RS. Geographic distribution of multiple sclerosis. Preliminary notes on a comparative study of prevalence in Charleston, S.C. and Halifax, N.S. Acta Psychiatrica Scandinavica Suppl. 1960;35(147):1822.Google ScholarPubMed
3. Alter, M, Talbert, OR, Allison, RS, Kurland, LT. The geographic distribution of multiple sclerosis. A comparative study in Charleston County, South Carolina and Halifax County, Nova Scotia. I. Prevalence in Charleston County, South Carolina. J S C Med Assoc. 1960;56:20913.Google Scholar
4. Patten, S. Integrating data from clinical and administrative databases in pharmacoepidemiological research. Can J Clin Pharmacol. 1998;5(2):927.Google Scholar
5. Marrie, RA, Yu, N, Blanchard, JF, Leung, S, Elliott, L. The rising prevalence and changing age distribution of multiple sclerosis in Manitoba. Neurology. 2010;74(6):46571.CrossRefGoogle ScholarPubMed
6. Canadian Institute for Health Information. Physicians in Canada: The status of Alternative Payment Programs 2005–2006. Ottawa: CIHI; 2008.Google Scholar
7. Sketris, I, Hicks, V, Brown, MJ, et al. Multiple sclerosis disease-modifying drug utilization patterns following introduction of a provincially funded program in Nova Scotia, Canada, 1998–2004. J Appl Ther Res. 2011;8(2):6578.Google Scholar
8. Polman, CH, Reingold, SC, Edan, G, et al. Diagnostic criteria for multiple sclerosis: 2005 revisions to the “McDonald Criteria”. Ann Neurol. 2005;58(6):8406.Google Scholar
9. McDonald, WI, Compston, A, Edan, G, et al. Recommended diagnostic criteria for multiple sclerosis: Guidelines from the international panel on the diagnosis of multiple sclerosis. Ann Neurol. 2001;50(1):1217.Google Scholar
10. Poser, CM, Paty, DW, Scheinberg, L, et al. New diagnostic criteria for multiple sclerosis: Guidelines for research protocols. Ann Neurol. 1983;13(3):22731.Google Scholar
11. Polman, CH, Reingold, SC, Banwell, B, et al. Diagnostic criteria for multiple sclerosis: 2010 Revisions to the McDonald criteria. Ann Neurol. 2011;69(2):292302.Google Scholar
12. Youden, WJ. Index for rating diagnostic tests. Cancer. 1950:325.Google ScholarPubMed
13. Landis, JR, Koch, GG. The measurement of observer agreement for categorical data. Biometrics. 1977;33(1):15974.Google Scholar
14. Miller, DH, Chard, DT, Ciccarelli, O. Clinically isolated syndromes. Lancet Neurol. 2012;11(2):15769.Google Scholar
15. Beck, CA, Metz, LM, Svenson, LW, Patten, SB. Regional variation of multiple sclerosis prevalence in Canada. Mult Scler. 2005;11(5):5169.Google Scholar
16. Hader, WJ, Yee, IML. Incidence and prevalence of multiple sclerosis in Saskatoon, Saskatchewan. Neurology. 2007;69(12):12249.Google Scholar
17. Marrie, R, Yu, B, Leung, S, et al. Rising prevalence of vascular comorbidities in MS: validation of administrative definitions for diabetes, hypertension, hyperlipidemia. Mult Scler. 2012;18(9):13109.Google Scholar
18. Warren, SA, Svenson, LW, Warren, KG. Contribution of incidence to increasing prevalence of multiple sclerosis in Alberta, Canada. Mult Scler. 2008;14(7):8729.Google Scholar
19. Fromont, A, Binquet, C, Sauleau, E, et al. National estimate of multiple sclerosis incidence in France (2001–2007). Mult Scler. 2012;18(8):110815.Google Scholar
20. Modrego, PJ, Pina, MA. Trends in prevalence and incidence of multiple sclerosis. J Neurol Sci. 2003;216:8993.CrossRefGoogle ScholarPubMed
21. Sloka, JS, Pryse-Phillips, WEM, Stefanelli, M. Incidence and prevalence of multiple sclerosis in Newfoundland and Labrador. Can J Neurol Sci. 2005;32:3742.Google Scholar
22. Alonso, A, Hernan, MA. Temporal trends in the incidence of multiple sclerosis: A systematic review. Neurology. 2008;71(2):12935.Google Scholar
23. Bostrom, I, Stawiarz, L, Landtblom, A-M. Sex ratio of multiple sclerosis in the National Swedish MS Register. Mult Scler. 2013; 19(1):4652.CrossRefGoogle ScholarPubMed
24. Culpepper, WJ, Ehrmantraut, M, Wallin, MT, Flannery, K, Bradham, DD. Veterans Health Administration multiple sclerosis surveillance registry: The problem of case-finding from administrative databases. J Rehabil Res Dev. 2006;43(1):17.Google Scholar
25. Theou, O, Rockwood, MR, Mitnitski, A, Rockwood, K. Disability and co-morbidity in relation to frailty: how much do they overlap? Arch Gerontol Geriatr. 2012;55(2):e18.Google Scholar
26. Ploughman, M, Austin, MW, Murdoch, M, et al. Factors influencing healthy aging with multiple sclerosis: a qualitative study. Disabil Rehabil. 2012;34(1):2633.Google Scholar