title: Beta-interferon protects multiple sclerosis patients against enhanced susceptibility to infections caused by poor air quality.
abstract: BACKGROUND
  The monthly multiple sclerosis relapse rate was studied from January 1995 to March 2001 from hospital records in Southwestern Finland as a retrospective open-label study.
  
  
  METHODS
  The relapse rates of beta-interferon users and nonusers were compared to ambient air inhalable particle levels and viral infections in the population with logistic regression.
  
  
  RESULTS
  In the non-user group, relapses were more frequent 1 month following the episodes when PM(10) was in the highest quartile [logistic regression odds ratio = 1.196 (95% CI = 1.019-1.404), p = 0.028] and following adenovirus epidemics in the general population [logistic regression odds ratio = 2.234 (95% CI = 1.013-4.926), p = 0.046]. PM(10) and virus infections had no significant effects in interferon users.
  
  
  CONCLUSIONS
  In addition to being antiviral, interferon also protected multiple sclerosis patients against an enhanced susceptibility to infections caused by PM(10).
authors.affiliation: Aerobiology Unit, University of Turku, Turku, Finland. mervi.oikonen@utu.fi
authors.forename: Mervi K
authors.initials: MK
authors.lastname: Oikonen
authors.forename: Juha-Pekka
authors.initials: JP
authors.lastname: Erälinna
mesh_terms: D000258:Adenovirus Infections, Human / Q000453:epidemiology / Q000276:immunology / Q000517:prevention & control*; D000328:Adult; D000397:Air Pollution / Q000009:adverse effects*; D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D015897:Comorbidity; D004198:Disease Susceptibility / Q000453:epidemiology / Q000276:immunology; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D007155:Immunologic Factors / Q000008:administration & dosage / Q000627:therapeutic use; D019570:Inhalation Exposure / Q000009:adverse effects*; D016899:Interferon-beta / Q000008:administration & dosage / Q000627:therapeutic use*; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D016017:Odds Ratio; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors
chemical_list: D000998:Antiviral Agents; D007155:Immunologic Factors; D016899:Interferon-beta