A Retrospective Database Study of Gastrointestinal Events and Medical Costs Associated with Nonsteroidal Anti-Inflammatory Drugs in Japanese Patients of Working Age with Osteoarthritis and Chronic Low Back Pain

Context: The real-world burden of gastrointestinal (GI) events associated with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in Japanese patients with osteoarthritis (OA) and/or chronic low back pain (CLBP) remains unreported. Objective: To assess the incidence and economic burden of NSAID-induced GI events by using data from large-scale real-world databases. Methods: We used the Japanese Medical Data Center database to retrospectively evaluate anonymized claims data of medical insurance beneficiaries employed by middle- to large-size Japanese companies who were prescribed NSAIDs for OA and/or CLBP between 2009 and 2018. Results: Overall, 180,371 patients were included in the analysis, of whom 32.9% had OA, 53.8% had CLBP, and 13.4% had both OA and CLBP. NSAIDs were administered as first-line analgesics to 161,152 (89.3%) of the patients in the sample, in oral form to 90.3% and as topical patches to 80.4%. A total of 65.1% used combined oral/topical patches. Of the 21.0% of patients consistently using NSAIDs (percentage of days supplied ≥70%), 54.5% received patches. A total of 51.5% patients used NSAIDs for >1 to ≤6 months. The incidence of GI events was 9.97 per 10,000 person-years (95% confidence interval: 8.92-11.03). The risk of developing GI events was high in elderly patients and patients with comorbidities and remained similar for patients receiving oral vs. topical NSAIDs. Longer treatment duration and consistent NSAID use increased the risk of GI events. The cost (median [interquartile range]) of medications (n = 327) was US$ 80.70 ($14.10, $201.40), that of hospitalization (n = 33) was US$ 2,035.50 ($1,517.80, $2,431.90), and that of endoscopic surgery (n = 52) was US$ 418.20 ($418.20, $418.20). Conclusion: NSAID-associated GI toxicity imposes a significant health and economic burden on patients with OA and/or CLBP, irrespective of whether oral or topical NSAIDs are used.