To print: Select File and then Print from your browser's menu --------------------------------------------------------------------------------------- Title: Gene Variants Influence Women's Response to Morphine After C-Section URL: http://www.pslgroup.com/dg/229DF2.htm Doctor's Guide August 25, 2008
NEW YORK -- August 25, 2008 -- Genetic variability of the A118G polymorphism impacts a woman's response to morphine when administered as post-Caesarean analgesia, according to a study in the September issue of Anesthesiology. "Information from this study could be the beginning of a systematic approach to develop a method of predicting pain threshold and morphine requirement for pain relief," said lead author Alex T. Sia, MD, KK Women's & Children's Hospital, Singapore. Previous studies have shown that genetic variability at position 118 of the human m-opioid receptor gene altered patients' responses to intravenous morphine. Therefore, the authors aimed to determine whether this polymorphism contributes to the variability in response to morphine for post-Caesarean analgesia. Dr. Sia and colleagues evaluated 588 healthy women who were injected with 0.1 mg morphine in the spinal canal after delivering their children via Caesarean section. Blood samples were obtained from all women and genotyped for the A118G polymorphism-A118 homozygous (AA), heterozygous (AG), or homozygous for the G allele (GG). Of the women, 270 (46%) were AA, 234 (40%) were AG, and 82 (14%) were GG. Pain scores, the severity of nausea and vomiting, the incidence of pruritus, and the total self-administered intravenous morphine were recorded for the first 24 postoperative hours. The 24-hour self-administered intravenous morphine consumption was lowest in the AA group (P = .001; mean, 5.9; 95% confidence interval [CI], 5.1-6.8) versus the AG (mean 8.0; CI, 6.9-9.1) and GG groups (mean 9.4; CI, 7.3-11.5). Pain scores were lowest in the AA group and highest in the GG group, with a statistically significant difference detected between AA, AG, and GG (P = .049). The AA group was associated with the highest incidence of nausea (9.6%, P = .02) versus the other 2 groups (5.6% for AG and 1.2% for GG). Overall, the study showed that various forms of the human opioid receptor have a significant effect on pain perception, analgesic requirement, and nausea for the first 24 hours after Caesarean section. Dr. Sia noted that the findings likely have important implications in differences among women's pain perception in general, pain after childbirth, and narcotic use after surgery. SOURCE: American Society of Anesthesiologists --------------------------------------------------------------------------------------------- Copyright © 1999 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content. --------------------------------------------------------------------------------------------- This news story was printed from *Doctor's Guide to the Internet* located at http://www.docguide.com --------------------------------------------------------------------------------------- Return to News Story Page This site is maintained by webmaster@pslgroup.com Please contact us with any comments, problems or bugs. All contents Copyright (c) 1998 P\S\L Consulting Group Inc. All rights reserved.