title: The prognostic value of initial relapses on the evolution of disability in patients with relapsing-remitting multiple sclerosis.
abstract: The evolution of multiple sclerosis (MS) and the resulting disability are unpredictable. To identify clinical variables that could be potential prognostic factors, we followed a cohort of 288 patients diagnosed as having relapsing-remitting MS between 1990 and 2003. The end point was the first occurrence of a non-reversible EDMUS-GS score >or=3 (moderate disability). The impact of the number of MS attacks during the first 2 years of the disease as well as the first interattack interval were assessed in two Cox models, one using a fixed-in-time covariate, the other using a time-dependent covariate. Older age at onset and a higher number of MS attacks during the first 2 years of MS proved to be predictors of unfavourable prognosis. The first interattack interval had no influence on the evolution of the disability, conversely to the first relapse which had a short-term impact on the prognosis. We confirmed that the age at onset and the number of MS attacks during the first 2 years of MS are predictors of the evolution of the disability and demonstrated the importance of using time-dependent covariates.
authors.affiliation: Department of Biostatistics and Medical Informatics, Centre Hospitalier Universitaire de Dijon, Dijon, France.
authors.forename: C
authors.initials: C
authors.lastname: Binquet
authors.forename: C
authors.initials: C
authors.lastname: Quantin
authors.forename: G
authors.initials: G
authors.lastname: Le Teuff
authors.forename: J F
authors.initials: JF
authors.lastname: Pagliano
authors.forename: M
authors.initials: M
authors.lastname: Abrahamowicz
authors.forename: T
authors.initials: T
authors.lastname: Moreau
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D002170:Canada / Q000453:epidemiology; D002391:Catchment Area, Health; D002648:Child; D019992:Databases as Topic; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000453:epidemiology* / Q000503:physiopathology*; D011379:Prognosis; D012008:Recurrence; D012720:Severity of Illness Index