title: Long-term outcome of paediatric-onset multiple sclerosis: a population-based study.
abstract: BACKGROUND
  Age of onset of multiple sclerosis (MS) peaks in the 3rd and 4th decades and is rarely less than 18. Robust longitudinal studies in paediatric-onset MS (POMS) are limited, and a clearer understanding of outcome could optimise management strategies.
  
  
  METHODS
  Patients with disease onset <18 years were identified from a prospective population-based register. Clinical features including presenting symptoms, time to Expanded Disability Status Scale (EDSS) 4.0, 6.0 and 8.0 and onset of secondary progression were compared with patients with adult-onset MS (AOMS).
  
  
  RESULTS
  111 POMS patients were identified from a cohort of 2068. No significant differences in sex ratio, familial recurrence, relapse rate, ethnicity or clinical symptoms at presentation were identified between POMS and AOMS. However, interval to second relapse was longer (5 vs 2.6 years, p=0.04) and primary progressive disease was less common (0.9% vs 8.5%, p=0.003) in POMS than in AOMS. POMS patients also took longer to develop secondary progressive disease (32 vs 18 years, p=0.0001) and to reach disability milestones (EDSS 4.0, 23.8 vs 15.5 years, p<0.0001; EDSS 6.0, 30.8 vs 20.4 years, p<0.0001; EDSS 8.0, 44.7 vs 39 years, p=0.02), but did so between 7.0 and 12 years younger than in AOMS.
  
  
  CONCLUSIONS
  5.4% of patients with MS have POMS (2.7% <16 years; 0.3% <10 years) and have distinct phenotypic characteristics in early disease. Furthermore, while patients with POMS take longer to reach disability milestones, they do so at a younger age than their adult counterparts and could be considered to have a poorer prognosis. Management strategies for these patients should take account of these data.
authors.affiliation: Institute of Psychological Medicine and Clinical Neuroscience, Cardiff University, University Hospital of Wales, Heath Park, Cardiff CF14 4XN, UK.
authors.forename: Katharine E
authors.initials: KE
authors.lastname: Harding
authors.forename: Kate
authors.initials: K
authors.lastname: Liang
authors.forename: Mark D
authors.initials: MD
authors.lastname: Cossburn
authors.forename: Gillian
authors.initials: G
authors.lastname: Ingram
authors.forename: Claire L
authors.initials: CL
authors.lastname: Hirst
authors.forename: Trevor P
authors.initials: TP
authors.lastname: Pickersgill
authors.forename: Johann
authors.initials: J
authors.lastname: Te Water Naude
authors.forename: Mark
authors.initials: M
authors.lastname: Wardle
authors.forename: Yoav
authors.initials: Y
authors.lastname: Ben-Shlomo
authors.forename: Neil P
authors.initials: NP
authors.lastname: Robertson
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000453:epidemiology*; D012008:Recurrence; D014852:Wales / Q000453:epidemiology