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Association between COMT Polymorphism Val158Met and Opioid Consumption in Patients with Postoperative Pain: A
Bo Hu1, Xiaomin Zhang2, Guangtao Xu1
1Department of Immunopathology and Diabetes Institute, Jiaxing Hospital of Traditional Chinese Medicine, Jiaxing University, Jiaxing, China.
Background/Aims:
Several factors influencing postoperative pain and the effect of opioid analgesics have been investigated on an individual level. The aim of this study was to clarify the impact of catecholamine-O-methyltransferase (COMT) gene Val158Met on opioid consumption in postoperative patients.
Methods:
A systematic review and meta-analysis of the literature up to September 30, 2017, were performed by using PubMed, Cochrane Library, ISI Web of Science, and Chinese National Knowledge Infrastructure (CNKI) database. The meta-analysis examined all studies involving the association between genetic polymorphisms of COMT Val158Met and opioid consumption during the acute postoperative period.
Results:
Of the 153 identified studies, 23 studies were retrieved for systematic review and 10 studies were retrieved for meta-analysis. However, it was impossible to conduct meta-analysis on the association between COMT Val158Met polymorphism and postoperative pain because of heterogeneity of the data. Overall, meta-analysis showed that COMT Val/Met carriers consumed less opioid for analgesia within the first 24 hours after surgery (SMD = 0.14, 95% CI = [0.03, 0.25], P = 0.01) but not within 48 hours (SMD = 0.14, 95% CI = [0.08, 0.36], P = 0.21). There was no significant difference in opioid consumption between Val/ Val and Met/Met patients.
Conclusion:
Patients with Val/Met but not Met/Met allele variant consumed less opioid, though larger and better-designed studies are required to obtain an exclusive conclusion about the correlation between postoperative pain and COMT Val158Met polymorphism.
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