Demyelinating events in rheumatoid arthritis after drug exposures

Ann Rheum Dis. 2010 Sep;69(9):1691-3. doi: 10.1136/ard.2009.111500. Epub 2009 Jul 23.


Objective: To estimate the effects of biological drugs on the risk of demyelinating events in rheumatoid arthritis (RA).

Methods: Case-control analyses nested in an administrative database cohort.

Results: Initially the risk of demyelinating events appeared to be increased after exposure to anakinra and decreased after exposure to antitumour necrosis factor (anti-TNF) agents. However, this apparent differential risk was due to more anakinra use (and avoidance of anti-TNF agents) in persons at high risk for demyelinating events. In individuals not at high risk, the adjusted rate ratio was 1.31 (95% CI 0.68 to 2.50) after exposure to anti-TNF agents and 0.80 (95% CI 0.29 to 2.24) after exposure to anakinra.

Conclusions: When accounting for differential prescription patterns, there was a trend towards more events after exposure to anti-TNF agents. When studying rare but important potential drug associations, pharmacoepidemiological studies are valuable but must be carefully performed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antirheumatic Agents / adverse effects*
  • Antirheumatic Agents / therapeutic use
  • Arthritis, Rheumatoid / drug therapy*
  • Arthritis, Rheumatoid / epidemiology
  • Canada / epidemiology
  • Case-Control Studies
  • Demyelinating Diseases / chemically induced*
  • Demyelinating Diseases / epidemiology
  • Female
  • Humans
  • Interleukin 1 Receptor Antagonist Protein / adverse effects
  • Interleukin 1 Receptor Antagonist Protein / therapeutic use
  • Male
  • Middle Aged
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors*


  • Antirheumatic Agents
  • Interleukin 1 Receptor Antagonist Protein
  • Tumor Necrosis Factor-alpha