Factors that Influence Prescribers in their Selection and use of COX-2 Selective Inhibitors as Opposed to Non-selective NSAIDs*

Abstract

To identify factors that influence prescribers in their selection and use of cyclo-oxygenase-2 (COX-2) selective inhibitors as opposed to non-selective non-steroidal anti-inflammatory drugs (NSAIDs) and report the tendency to co-prescribe gastro-protection with these agents. All 579 general practitioners (GPs) in one geographical area, Lothian, Scotland, UK. Postal questionnaires; simple and factorial designed case series questionnaire. Categorisation of responses to clinical and non-clinical factors into highly, partially or not influential. The quantitative influence of the most prominent clinical factors on prescribing choice and the tendency of co-prescription of gastro-protection with these agents. Responses from 229 (40%) GPs suggested the following as most influential: Drug Evaluation Panel recommendations, Lothian Joint Formulary, local practice formulary, history of peptic ulcer disease (PUD), history of gastro-intestinal (GI) adverse effects with NSAIDs and advanced age. Advice from other physicians, patient demand, history of alcohol gastritis, history of gastro-oesophageal reflux disease, history of functional dyspepsia, concomitant use of low dose aspirin and concomitant use of gastro-protective agents were regarded to have moderate influence. Information directly from pharmaceutical industry and regular smoking were regarded as having weak influence. An 18% response to the factorial designed questionnaire using the most prominent clinical factors suggested that history of either GI adverse effects associated with non-selective NSAIDs or PUD resulted in more pronounced increase in the frequency (15%) of decision to prescribe COX-2 selective inhibitors than advanced age (10%). Concomitant use of low dose aspirin had little effect on GPs' decisions. The mean percentage of GPs choosing to co-prescribe gastro-protection was higher with non-selective NSAIDs (64%) than with COX-2 selective inhibitors (22%). Local authoritative guidance and history of GI complications highly influenced the GPs in their use and choice of either COX-2 selective inhibitors or non-selective NSAIDs. As expected the use of gastro-protection was more frequently chosen with non-selective NSAIDs than COX-2 selective inhibitors.