Pharmacoeconomic implications of interchangeable use of oral NSAIDS for pain management at a district hospital.

Abstract

Background: Ibuprofen, diclofenac and aspirin belong to the same class of drugs called NSAIDs, but are used interchangeably at Tonga Hospital. The problem with this approach is that it may lead to preventable misguided and increased spending on pharmaceuticals. Aim: To investigate the pharmacoeconomic implications of interchangeable use of oral NSAIDs for pain management at a district hospital. Setting: This study was conducted at a district hospital in the Tonga village in the Nkomazi municipality, Mpumalanga Province, South Africa. Methods: A quantitative retrospective descriptive study, using existing patient records as well as medicine stock control records, was conducted to investigate the cost-effectiveness of oral NSAIDs when used interchangeably in the management of pain in adult patients at a district hospital. Results: The total number of patients included in this study was 211 in a split of 104 in 2013 and 107 in 2014. The mean ages of all the patients who participated in our study in 2013 and 2014 were 36 and 35 years respectively and there were more females than males. Most patients who presented at Tonga Hospital for pain management were suffering from minor bodily/joint pains (36.0%, n=76), whereas the least number of patients were suffering from bone fractures (10.9%, n=23). Our study found that most patients (31.3%; n=66) treated with ibuprofen were suffering from minor bodily/joint pains, whereas the least number of patients (1.4%; n=3) treated with diclofenac were suffering from inflammatory conditions. Females were the largest users of NSAIDs (both ibuprofen and diclofenac) in Tonga Hospital when compared with males. Patients between the ages of 19-35 years were the most prevalent (28.4%, n=60) who were treated with ibuprofen when compared with patients 18 years and below (9.5%, n=20). Also, patients who were 18 years and younger and treated with diclofenac were the least number of patients (1.4%, n=3). The highest total NSAID stock volumes issued from July to December of 2013 and 2014 combined was ibuprofen (36978 packs) when compared with diclofenac (11127 packs). The stock volumes for both ibuprofen and diclofenac were higher in July, with 8170 for Ibuprofen and 2099 for diclofenac. Diclofenac stock volumes fell to their lowest (1583) in September, whereas Ibuprofen stock volumes fell to their lowest (4478) in December. The fall in stock volumes issued might be attributable to many factors including but not limited to non-delivery by the supplier or non-ordering by the pharmacy staff. In all instances ibuprofen stock volumes issued were higher than that of diclofenac. The acquisition cost of ibuprofen when calculated as mean price per tablet during 2013 to 2014 was consistently lower, with an average price of (0.285 ZAR) when compared with diclofenac (0.995 ZAR). 0.3% of the population of Nkomazi east, on average, gets treatment of ibuprofen daily whereas 0.01% of the population gets treatment of diclofenac daily. The mean cost per defined daily dose was consistently lower for ibuprofen in both 2013 (0.84 ZAR) and 2014 (0.87 ZAR) when compared with diclofenac in 2013 (2.94 ZAR) and 2014 (3.03 ZAR). The sensitivity analysis points in favour of ibuprofen over diclofenac as indicated when increasing or decreasing the mean price per tablet by 50% of either ibuprofen or diclofenac. Conclusion: This study found that the acquisition costs of NSAIDs in relation to the mean price per pack of oral tablets had been consistently higher for diclofenac than they were for ibuprofen in Tonga Hospital. Therefore, the use of ibuprofen oral tablets in the management of pain at a district hospital is cost-effective when compared with diclofenac oral tablets.