Ethnicity and OPRM variant independently predict pain perception and patient-controlled analgesia usage for post-operative pain

doi:10.1186/1744-8069-5-32

Molecular Pain

Volume 5

Viewing options:

Abstract
Full text
PDF (297KB)

Associated material:

Related literature:

Articles citing this article
on Google Scholar
on ISI Web of Science
on PubMed Central
Other articles by authors
on Google Scholar

Tan E
Lim EC
Teo Y
Lim Y
Law H
Sia AT

on PubMed

Tan E
Lim EC
Teo Y
Lim Y
Law H
Sia AT
Related articles/pages
on Google

on Google Scholar

on PubMed

Tools:

Post to:

Research

Ethnicity and OPRM variant independently predict pain perception and patient-controlled analgesia usage for post-operative pain

Ene-choo Tan¹^,2 , Eileen CP Lim¹ , Yik-ying Teo³ , Yvonne Lim⁴ , Hai-yang Law⁵ and Alex T Sia¹^,4

¹KK Research Centre, KK Women's and Children's Hospital, Singapore

²Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore

³Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK

⁴Department of Women's Anesthesia, KK Women's and Children's Hospital, Singapore

⁵Genetics Service, KK Women's and Children's Hospital, Singapore

author email corresponding author email

Molecular Pain 2009, 5:32doi:10.1186/1744-8069-5-32


Published:	23 June 2009

Abstract

Background

Morphine consumption can vary widely between individuals even for identical surgical procedures. As mu-opioid receptor (OPRM1) is known to modulate pain perception and mediate the analgesic effects of opioid compounds in the central nervous system, we examined the influence of two OPRM polymorphisms on acute post-operative pain and morphine usage in women undergoing elective caesarean delivery.

Results

Data on self-reported pain scores and amount of total morphine use according to patient-controlled analgesia were collected from 994 women from the three main ethnic groups in Singapore. We found statistically significant association of the OPRM 118A>G with self-administered morphine during the first 24-hour postoperative period both in terms of total morphine (p = 1.7 × 10^-5) and weight-adjusted morphine (p = 6.6 × 10^-5). There was also significant association of this OPRM variant and time-averaged self-rated pain scores (p = 0.024). OPRM 118G homozygotes used more morphine and reported higher pain scores than 118A carriers. Other factors which influenced pain score and morphine usage include ethnicity, age and paying class.

Conclusion

Our results suggest that ethnicity and OPRM 118A>G genotype are independent and significant contributors to variation in pain perception and postoperative morphine use in patients undergoing cesarean delivery.