Determinants of selective cyclooxygenase-2 inhibitor prescribing: are patient or physician characteristics more important?

Am J Med. 2003 Dec 15;115(9):715-20. doi: 10.1016/j.amjmed.2003.08.025.


Background: Little is known about which factors influence the widespread use of selective cyclooxygenase (COX)-2 inhibitors. We examined the relative effects of patient risk factors for gastrointestinal toxicity, other patient characteristics, and physician prescribing preferences on the decision to prescribe a selective COX-2 inhibitor.

Methods: We retrospectively studied a cohort of 28,190 Medicare beneficiaries who were continuously enrolled in a large, state-run pharmacy benefits program that reimbursed for selective COX-2 inhibitors and nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) without restrictions. Half of the study sample filled a prescription for a selective COX-2 inhibitor and the other half for a nonselective NSAID. Multivariable logistic regression models were developed to predict COX-2 inhibitor use.

Results: Seventeen percent of patients using a COX-2 inhibitor had no identifiable risk factor for NSAID-associated gastrointestinal toxicity, compared with 23% of those using a nonselective NSAID. Established risk factors (age > or =75 years, history of gastrointestinal hemorrhage or peptic ulcer disease, or concomitant warfarin or oral glucocorticoid use) were all significant predictors of COX-2 inhibitor use, but a multivariable model including only these risk factors discriminated poorly between the two patient groups (C statistic = 0.55). Adding other patient clinical and demographic characteristics to the model somewhat improved this association (C statistic = 0.66); however, when physician prescribing preference was included, the model had excellent ability to discriminate between the two treatment groups (C statistic = 0.83).

Conclusion: Established risk factors for NSAID-associated gastrointestinal toxicity were poor predictors of who was prescribed a selective COX-2 inhibitor; in contrast, physician prescribing preference was an important determinant.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use
  • Arthritis, Rheumatoid / chemically induced
  • Cohort Studies
  • Cyclooxygenase Inhibitors / adverse effects
  • Cyclooxygenase Inhibitors / therapeutic use*
  • Drug Prescriptions*
  • Female
  • Gastrointestinal Diseases / chemically induced
  • Humans
  • Logistic Models
  • Male
  • Osteoarthritis / chemically induced
  • Pennsylvania / epidemiology
  • Physician-Patient Relations
  • Predictive Value of Tests
  • Retrospective Studies
  • Risk Factors


  • Anti-Inflammatory Agents, Non-Steroidal
  • Cyclooxygenase Inhibitors