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Use of newer anti-inflammatory drugs causing increase in hospitalizations for GI bleeding


The rapid increase in the use of COX-2 inhibitors may have resulted in a significant jump in the number of hospital admissions for GI bleeding in Ontario, a new study from the Institute for Clincal Evaluative Sciences (ICES) has found.

COX-2 inhibitors are a new group of drugs that are part of a larger drug class called non-steroidal anti-inflammatory drugs (NSAIDs). Clinicians and patients have been quick to embrace COX-2 inhibitors (celecoxib, rofecoxib, and meloxicam) because they are supposed to cause less gastrointestinal (GI) bleeding than traditional NSAIDs. However, recent research has shown certain COX-2 inhibitors are not completely without the risk of GI bleeding.

To assess the impact of COX-2 inhibitors on adverse GI events, ICES researchers tracked population-based changes in the overall use of NSAIDs, as well as hospitalizations for GI bleeding, among the entire elderly population of approximately 1.4 million Ontarians 66 years of age and older between Sept. 1994 and Feb. 2002.


  • Overall NSAID use increased by 41%. This was entirely due to increased COX-2 inhibitor use – from 14% of the elderly population actively taking NSAIDs just before the introduction of COX-2 inhibitors, to 20% taking COX-2s by 2002.
  • The rate of hospitalization for GI bleeding increased by 10% from about 15 per 10,000 elderly persons just prior to COX-2 inhibitor introduction, to about 17 per 10,000 elderly persons by the end of the study period. This translates to at least 650 additional hospital admissions for GI bleeds annually among the elderly following the introduction of the COX-2 inhibitors in Ontario.


“Even though COX-2 inhibitors may have a lower risk of GI bleeding at the individual level than traditional NSAIDs, their rapid use in so many elderly patients has had an apparent paradoxical adverse impact on the population,” said lead author and ICES Scientist Dr. Muhammad Mamdani.

“As well, people continue to take COX-2s longer than traditional NSAIDs because of fewer concerns on both the part of patients and physicians about the risk of GI bleeds. This could also be a factor in explaining our results.”

Dr. Mamdani and his fellow co-authors stress the “pressing need to further characterize the population risks of COX-2 inhibitors to better understand the risk-to-benefit tradeoffs associated with their widespread use.”

The study, “Gastrointestinal bleeding after the introduction of COX 2 inhibitors: ecological study”, is in the June 12, 2004 issue of the British Medical Journal (BMJ).

Author affiliations: ICES (all authors); University of Toronto Faculties of Pharmacy (Dr. Mamdani) and Medicine (Drs. Mamdani, Juurlink, Naglie, Austin, and Laupacis); Sunnybrook and Women’s College Health Sciences Centre (Drs. Juurlink and Laupacis); University Health Network and Toronto Rehabilitation Institute (Dr. Naglie)

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners and practitioners to make decisions about care delivery and to develop policy.


  • Julie Argles
  • Media Relations Officer, ICES
  • (416) 480-4780 or cell (416) 432-8143


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