Have COX-2 inhibitors influenced the co-prescription of anti-ulcer drugs with NSAIDs?
OBJECTIVE
To quantify usage of COX-2 inhibitors compared with nonselective NSAIDs and to determine their impact (including financial) on the co-prescription of antipeptic ulcer (anti-PU) drugs.


METHODS
The Irish General Medical Services prescription database (covering 1.2 million people) was examined for NSAID prescriptions during December 1999-November 2001. NSAID users were excluded during the first 6 months. During the next 12 months (study period) patients on NSAIDs (>or= 3 prescriptions) were identified. The study period and final 6 months provided data on co-prescription of anti-PU drugs. Age, gender, number of concomitant prescriptions, co-prescribing of anti-PU drugs and monthly cost were evaluated for 8 NSAIDs (n= 4 non-selective NSAIDs and n= 4 COX-2 inhibitors) and odds ratios (OR) calculated using logistic regression.


RESULTS
COX-2 inhibitors were prescribed more frequently in older, female patients and those receiving multiple medications. After adjustment for age, gender and polypharmacy, anti-PU drugs were prescribed more frequently with COX-2 inhibitors (OR = 1.31 (1.23,1.40)). COX-2 inhibitors were up to 10-fold more expensive, median monthly costs (including anti-PU drugs) ranging from Euros 34.61 (COX-2 inhibitors) to Euros 3.26 (nonselective NSAIDs).


CONCLUSIONS
Since COX-2 inhibitors are associated with increased rates of co-prescription of anti-PU drugs and are more expensive than non-selective NSAIDs, these results suggest that the expected cost-savings with COX-2 inhibitors may not be occurring in practice.
Department of Pharmacology and Therapeutics, Trinity College/St James's Hospital, Dublin 8, Ireland. teelingm@tcd.ie
Mary
M
Teeling
Kathleen
K
Bennett
John
J
Feely
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000897:Anti-Ulcer Agents / Q000191:economics / Q000627:therapeutic use*; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000191:economics / Q000627:therapeutic use*; D016527:Drug Costs; D004347:Drug Interactions; D011307:Drug Prescriptions / Q000191:economics; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors* / Q000191:economics; D008297:Male; D008565:Membrane Proteins; D008875:Middle Aged; D010437:Peptic Ulcer / Q000188:drug therapy* / Q000191:economics; D010818:Practice Patterns, Physicians'; D011451:Prostaglandin-Endoperoxide Synthases / Q000191:economics; D012044:Regression Analysis
D000894:Anti-Inflammatory Agents, Non-Steroidal; D000897:Anti-Ulcer Agents; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D007527:Isoenzymes; D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases