title: Meta-analysis of clinical studies of the efficacy of plasma exchange in the treatment of chronic progressive multiple sclerosis.
abstract: OBJECTIVE
  To examine the hypothesis that addition of therapeutic plasma exchange (TPEX) to an immunosuppressive drug regimen increases that regimen's efficacy to halt the progression of chronic progressive multiple sclerosis (CPMS).
  
  
  METHODS
  The literature was searched for prospective controlled clinical trials evaluating the efficacy of TPEX in CPMS. Six studies were eligible for meta-analysis. Their results were combined, using Cochran's and Peto's methods. Three outcome measures were studied: 1) the change in Kurtzke's disability status scale (DSS) scores, 2) the relative odds of neurologic decline by 1 or more DSS grades, and 3) the relative odds of neurologic improvement by 1 or more DSS grades, in the treatment versus the comparison group of patients. Reported results of neurologic evaluations at 6, 12, 24, and 36 months of follow-up were analyzed separately.
  
  
  RESULTS
  TPEX significantly (P < .05) reduced the proportion of patients who experienced neurologic decline (by 1 or more DSS grades) at 12 months of follow-up (relative odds of decline = 0.441, 95% confidence interval = 0.210-0.929).
  
  
  CONCLUSIONS
  There is a need for further clinical research into the possibility of a beneficial effect of TPEX in patients with CPMS likely to experience neurologic decline over the ensuring 12 months. Targeting treatment to a particular subgroup of CPMS patients may be necessary for TPEX to prove effective.
authors.affiliation: Blood Transfusion Service, Massachusetts General Hospital, Boston 02114, USA.
authors.forename: E C
authors.initials: EC
authors.lastname: Vamvakas
authors.forename: A A
authors.initials: AA
authors.lastname: Pineda
authors.forename: B G
authors.initials: BG
authors.lastname: Weinshenker
mesh_terms: D002908:Chronic Disease; D018450:Disease Progression; D006801:Humans; D009103:Multiple Sclerosis / Q000473:pathology / Q000628:therapy*; D016017:Odds Ratio; D010951:Plasma Exchange; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D016896:Treatment Outcome