title: Specific clinical phenotypes in relapsing multiple sclerosis: The impact of relapses on long-term outcomes.
abstract: OBJECTIVE
  The impact of relapses on the disease course of relapsing MS remains to be determined. This study aims to identify and characterize clinical phenotypes of relapse onset MS in a longitudinally studied cohort.
  
  
  METHODS
  We recorded the clinical course of MS during the first decade of disease, using five-year epochs. Patients were stratified as: no worsening due to relapse or secondary progression (type A), relapse with worsening seen without secondary progression (type B), secondary progression with no worsening due to relapse (type C), worsening due to relapses mixed with secondary progression (type D).
  
  
  RESULTS
  Of 176 patients followed from diagnosis for 12.62 ± 4.18 years, 93.2% (164/176) had increased disability in their first 5-year epoch of MS and 52.2% (72/138) in the next. The phenotypes significantly differed by EDSS change during each epoch (p<0.001), final confirmed MSSS (p ≤ 0.002) and relapse rate (p<0.001). Type D fared worse than others by change in EDSS and MSSS.
  
  
  CONCLUSIONS
  We identified multiple specific phenotypes of MS and temporal shifts between phenotypes according to relapse type and progression.
authors: Allegheny General Hospital, Department of Neurology, Pittsburgh, USA; Drexel University College of Medicine, Department of Neurology, Pittsburgh, USA. Electronic address: tscott@wpahs.org.
authors: Thomas F
authors: TF
authors: Scott
authors: Allegheny General Hospital, Department of Neurology, Pittsburgh, USA; Temple University School of Medicine, Department of Neurology, Philadelphia, USA.
authors: Edward J
authors: EJ
authors: Gettings
authors: Allegheny General Hospital, Department of Neurology, Pittsburgh, USA; University of South Carolina, Department of Psychology, Columbia, USA.
authors: Christopher T
authors: CT
authors: Hackett
authors: Allegheny General Hospital, Department of Neurology, Pittsburgh, USA; Drexel University College of Medicine, Department of Neurology, Pittsburgh, USA.
authors: Carol J
authors: CJ
authors: Schramke
mesh_terms: D000328:Adult; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000175:diagnosis*; D010641:Phenotype
keywords: Multiple sclerosis; Natural history; Phenotypes; Progression; Relapse; Worsening