Effects of Genetic Polymorphisms on Efficacy and Safety of Opioid Analgesics in Patients with Postoperative Pain in a Taiwanese Population

Opioids are the most common analgesics used for the treatment of acute and chronic pain over the past decade. However, the sensitivity to opioid analgesics is highly variable, leading to difference in analgesic efficacy and adverse effects between individual subjects. Some patients experience inadequate analgesia despite escalating doses. Also, Opioid-related adverse effects, such as miosis, drowsiness, nausea, vomiting, constipation, and respiratory depression, challenge the compliance and continuation of the therapy for pain management. This interindividual variability in the sensitivity to opioid analgesics is only partially explained by environmental factors; and evidence from previous studies have indicated that genetic polymorphisms might be responsible for variation of opioid sensitivity in patients. Therefore, investigation of the association between genetic variants and the analgesic effects of opioids is vital for the precision of pain management, and early detection and prevention of adverse effects.The aim of this study is to investigate the association between the genetic polymorphisms and opioid sensitivity in postoperative patients. Patients who are scheduled for operation, and used analgesic for postoperative pain management will be recruited. The clinical and physiological data of the patients including morphine consumption, doses of analgesics, visual analogue score (VAS) of pain, Electrocardiography (ECG), Photoplethysmography (PPG), Galvanic skin response (GSR), and adverse effects related to opioid use, will be recorded during postoperative period.In this study, we will use several tools, including genome-wide association study (GWAS), next generation sequencing (NGS) and genotyping, to identify important genetic polymorphisms. We expect this study to further elucidate the role of genetic polymorphisms for the opioid efficacy and safety in postoperative patients in Taiwanese population.