Use of NSAIDs, COX‐2 inhibitors, and acetaminophen and associated coprescriptions of gastroprotective agents in an elderly population

OBJECTIVES: To identify determinants of cyclooxygenase 2 (COX-2) inhibitor versus nonsteroidal antiinflammatory drug (NSAIDs) or acetaminophen prescription in seniors; and to compare gastroprotective agent coprescriptions. METHODS: Administrative medical records were obtained from the government of Quebec health insurance agency. Three cohorts were formed based on prescriptions at study entry: COX-2 inhibitors, NSAIDs, or acetaminophen. Logistic regressions were used to adjust for potential confounders. RESULTS: We identified 42,267 patients taking COX-2 inhibitors, 8,235 taking NSAIDs, and 19,716 taking acetaminophen. Determinants of utilizing COX-2 inhibitors versus NSAIDs and versus acetaminophen, respectively, include: female gender (odds ratio [OR] 1.47; 95% confidence interval [95% CI] 1.39-1.55 and OR 1.17; 95% CI 1.12-1.22); musculoskeletal diseases (OR 1.87; 95% CI 1.76-2.00 and OR 2.20; 95% CI 2.10-2.31); and prior gastrointestinal hospitalization (OR 1.82; 95% CI 1.19-2.78 and OR 0.77; 95% CI 0.64-0.92). Gastroprotective agent coprescriptions were lower with COX-2 inhibitors than NSAIDs: OR 0.53; 95% CI 0.48-0.58. CONCLUSIONS: COX-2 inhibitors were more commonly used than NSAIDs in patients with musculoskeletal diseases and those with prior gastrointestinal hospitalizations. Adjusted odds ratios showed a 47% decrease in gastroprotective agent coprescriptions with COX-2 inhibitors compared with NSAIDs.