title: Does MRI lesion activity regress in secondary progressive multiple sclerosis?
abstract: BACKGROUND
  The rate of new contrast-enhancing lesions (CELs) on monthly magnetic resonance imaging (MRI) scans has been shown to decrease over a 9-month period in placebo-treated patients with relapsing-remitting (RR) multiple sclerosis (RRMS).
  
  
  OBJECTIVE
  We examined this phenomenon in placebo-treated secondary progressive MS (SPMS) patients.
  
  
  METHODS
  Patients were chosen from two clinical trials. Monthly scans were taken at screening, baseline and months 1-9 for Cohort-1 and months 1-6 for Cohort-2. We examined the monthly new CEL rates according to initial CEL level: 0, 1-3, >3 CELs at screening, and presence and absence of pre-study relapses.
  
  
  RESULTS
  Respectively, 59, 21 and 14 of the 94 Cohort-1 patients, and 36, 17 and 9 of the 62 Cohort-2 patients had 0, 1-3 and >3 initial CELs. For Cohort-1, the monthly new CEL rates did not change during follow-up, regardless of initial CEL level. For Cohort-2, the monthly rate was unchanged in the 0 initial CEL subgroup, but decreased 33% (95% confidence interval: 8%, 52%) from months 1-3 to months 4-6 in the other two subgroups. For the combined cohorts, a decreasing rate was observed in the 12 patients with >3 initial CELs and pre-study relapses.
  
  
  CONCLUSIONS
  The short-term trend of new CEL activity in placebo-treated SPMS patients may vary across cohorts.
authors.affiliation: MS/MRI Research Group, Department of Medicine, University of British Columbia, Vancouver, Canada. yinshan@msmri.medicine.ubc.ca
authors.forename: Y
authors.initials: Y
authors.lastname: Zhao
authors.forename: A J
authors.initials: AJ
authors.lastname: Petkau
authors.forename: A
authors.initials: A
authors.lastname: Traboulsee
authors.forename: A
authors.initials: A
authors.lastname: Riddehough
authors.forename: D K B
authors.initials: DK
authors.lastname: Li
mesh_terms: D000328:Adult; D001921:Brain / Q000473:pathology*; D017322:Clinical Trials, Phase II as Topic; D017326:Clinical Trials, Phase III as Topic; D003287:Contrast Media; D018450:Disease Progression; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D020528:Multiple Sclerosis, Chronic Progressive / Q000175:diagnosis*; D015990:Placebo Effect; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic; D013997:Time Factors
chemical_list: D003287:Contrast Media