title: Rate of brain atrophy in relapsing MS decreases during treatment with IFNbeta-1a.
abstract: OBJECTIVE
  To determine the time course of brain atrophy during treatment with once-weekly IM interferon beta-1a (IFNbeta-1a).
  
  
  METHODS
  The MRI cohort (n = 386) of the European IFNbeta-1a dose comparison study in relapsing multiple sclerosis (MS) was analyzed. In addition to baseline and three annual scans, a frequent subgroup (n = 138) had two scans before treatment initiation and scans at months 4, 5, 6, 10, and 11. Brain parenchymal fraction (BPF), a normalized measure of whole-brain atrophy, and volume of Gd-enhancing lesions (T1Gd) and T2 hyperintense lesions (T2LL) were evaluated.
  
  
  RESULTS
  BPF decrease was -0.686% (first year), -0.377% (second year), and -0.378% (third year). Analysis of the frequent subgroup showed that 68% of the first-year BPF decrease occurred during the first 4 months of treatment. This change was paralleled by a drop in T1Gd and T2LL. In the frequent subgroup, an annualized atrophy rate was determined by a regression slope for the pretreatment period and from month 4 of treatment onward. Annualized pretreatment rate (-1.06%) was significantly higher than the under-treatment rate (-0.33%).
  
  
  CONCLUSIONS
  In the first year of treatment with anti-inflammatory agents, atrophy measurements are possibly confounded by resolution of inflammatory edema or more remote effects of previous damage to the CNS. The atrophy rate reduction observed after treatment month 4 may reflect a beneficial but partial effect of interferon beta-1a and was sustained over the 3-year study period.
authors.affiliation: MS MRI Evaluation Centre Basel, University Hospitals Basel, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Hardmeier
authors.forename: S
authors.initials: S
authors.lastname: Wagenpfeil
authors.forename: P
authors.initials: P
authors.lastname: Freitag
authors.forename: E
authors.initials: E
authors.lastname: Fisher
authors.forename: R A
authors.initials: RA
authors.lastname: Rudick
authors.forename: M
authors.initials: M
authors.lastname: Kooijmans
authors.forename: M
authors.initials: M
authors.lastname: Clanet
authors.forename: E W
authors.initials: EW
authors.lastname: Radue
authors.forename: L
authors.initials: L
authors.lastname: Kappos
mesh_terms: D000328:Adult; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D015331:Cohort Studies; D018450:Disease Progression; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D000068556:Interferon beta-1a; D016899:Interferon-beta / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy / Q000473:pathology*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D007155:Immunologic Factors; D016899:Interferon-beta; D000068556:Interferon beta-1a