title: Multiple sclerosis after infectious mononucleosis: record linkage study.
abstract: OBJECTIVE
  To ascertain if infectious mononucleosis is a risk factor for the development of multiple sclerosis (MS); and, if it is, whether its effect is close to or remote in time from the onset of MS.
  
  
  METHODS
  Analysis of database of linked abstracts of records of hospital admission and death.
  
  
  METHODS
  Health region in central southern England.
  
  
  METHODS
  Ratio of rate of MS in a cohort of people admitted to hospital with infectious mononucleosis to the rate in a comparison cohort.
  
  
  RESULTS
  Considering all time intervals from admission with infection to admission with MS, there was a non-significant increase of risk of MS in the infectious mononucleosis cohort (rate ratio 2.17, 95% confidence intervals 0.79 to 4.77). At the interval of 10 years or more, there was a significant increase in risk of MS (rate ratio 4.01, 1.48 to 8.93). The mean time from infectious mononucleosis to first admission with MS was 14 years.
  
  
  CONCLUSIONS
  This study adds support to the evidence that Epstein-Barr virus, the cause of infectious mononucleosis, is associated with MS. Its role is probably as an initiator of the disease process of MS, or as a contributor to its early development, rather than as an activator of latent, existing disease.
authors.affiliation: Unit of Health-Care, Department of Public Health, University of Oxford, Old Road, Oxford OX3 7LF, UK. michael.goldacre@dphpc.ox.ac.uk
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Goldacre
authors.forename: Clare J
authors.initials: CJ
authors.lastname: Wotton
authors.forename: Valerie
authors.initials: V
authors.lastname: Seagroatt
authors.forename: David
authors.initials: D
authors.lastname: Yeates
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D004739:England / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007244:Infectious Mononucleosis / Q000150:complications* / Q000453:epidemiology; D008498:Medical Record Linkage; D009103:Multiple Sclerosis / Q000453:epidemiology / Q000821:virology*; D012307:Risk Factors