Background and Objective: Opioid-induced nausea and vomiting (OINV) is known to develop not only upon opioid introduction but also during opioid dose escalation, but the actual details are unclear. The aim of this study was to investigate the frequency of OINV in opioid dose escalation at a single center and to identify risk factors. Methods: A retrospective analysis of the medical records of hospitalized patients with cancer who underwent increased intake of oral oxycodone extended-release tablets at Komaki City Hospital between January 2016 and December 2019 was performed. Associations between the incidence of OINV and multiple factors were analyzed, including patient demographics, opioid daily dose, comorbidities, history of nausea after opioid introduction, and prophylactic antiemetic drugs. Results: Of the 132 patients analyzed, 56 (42.4%; grades 1 and 2, 36 and 20, respectively) developed opioid-induced nausea after opioid dose escalation, 26 (19.7%; grades 1 and 2, 19 and 7, respectively) developed opioid-induced vomiting, 58 (43.9%) had either opioid-induced nausea or vomiting. Thirty-five of 60 patients (55.0%) developed OINV among those who received prophylactic antiemetic drugs at opioid dose escalation. Performance status (≥2) (odds ratio [OR]: 2.36, 95% confidence interval [95% CI]: 1.15-4.84, p = 0.02) and history of nausea for opioid introduction (OR: 2.92, 95% CI: 1.20-7.10, p = 0.02) were detected as risk factors for the development of OINV. Conclusion: This study revealed a high incidence of OINV during opioid dose escalation, indicating that careful monitoring is required as at the time of opioid introduction. Further validation by a prospective study is required.
Keywords: nausea; opioid; opioid dose escalation; vomiting.