title: Gender effects on treatment response to interferon-beta in multiple sclerosis.
abstract: BACKGROUND
  Gender appears to play a role in incidence and disease course of multiple sclerosis (MS).
  
  
  OBJECTIVE
  The objective was to determine whether male and female patients with MS respond differently to interferon-beta treatment in terms of reduction in relapse rates.
  
  
  METHODS
  We included all 2033 patients with relapsing-remitting MS who started treatment with interferon-beta from 1996 to 2003, identified from the Danish Multiple Sclerosis Treatment Register. We defined neutralizing antibody (NAb)-positive and NAb-negative periods in the single patient by the results of the NAb tests. Patients served as their own controls, and relapse rates were compared between NAb-negative and NAb-positive periods.
  
  
  RESULTS
  NAbs significantly abrogated the interferon-beta treatment efficacy in both genders. The all-over women:men relapse rate ratio irrespective of NAb status was 1.47 (95%CI; 1.28-1.68). In a generalized linear Poisson models analysis with relapse counts as response variable, the main effects NAbs, sex, age at treatment start and number of relapses in 2 years before treatment start were strongly significant, but the effect of NAbs on relapse rates did not differ significantly between men and women.
  
  
  CONCLUSIONS
  As NAbs influenced the on-treatment relapse rates strongly in both sexes but without statistical significant difference, there is no indication of different effects of interferon-beta in men or women.
authors.affiliation: Danish Multiple Sclerosis Center, Department of Neurology, and the Danish Multiple Sclerosis Registry, Rigshospitalet and University of Copenhagen, Copenhagen, Denmark.
authors.forename: M
authors.initials: M
authors.lastname: Magyari
authors.forename: N
authors.initials: N
authors.lastname: Koch-Henriksen
authors.forename: B
authors.initials: B
authors.lastname: Laursen
authors.forename: P S
authors.initials: PS
authors.lastname: Sørensen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D057134:Antibodies, Neutralizing / Q000097:blood*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D016899:Interferon-beta / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood / Q000188:drug therapy*; D012008:Recurrence; D012727:Sex Characteristics; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; D007155:Immunologic Factors; D016899:Interferon-beta
keywords: Demyelinating diseases; gender differences; immunomodulatory treatment; interferon; multiple sclerosis; neutralizing antibodies; treatment response