Back to Journals » Neuropsychiatric Disease and Treatment » Volume 10

Evaluation of clinical and inflammatory profile in opioid addiction patients with comorbid pain: results from a multicenter investigation

Authors Dennis B, Samaan MC, Bawor M, Paul J, Plater C, Pare G, Worster A, Varenbut M, Daiter J, Marsh D, Desai D, Thabane L, Samaan Z

Received 16 August 2014

Accepted for publication 8 September 2014

Published 19 November 2014 Volume 2014:10 Pages 2239—2247


Checked for plagiarism Yes

Review by Single anonymous peer review

Peer reviewer comments 3

Editor who approved publication: Dr Roger Pinder

Brittany B Dennis,1 M Constantine Samaan,2 Monica Bawor,3 James Paul,4 Carolyn Plater,5 Guillaume Pare,1 Andrew Worster,6 Michael Varenbut,5 Jeff Daiter,5 David C Marsh,5,7 Dipika Desai,8 Lehana Thabane,1,9,10 Zainab Samaan1,8,11

1Department of Clinical Epidemiology and Biostatistics, 2Department of Pediatrics, Division of Pediatric Endocrinology, 3McMaster Integrative Neuroscience Discovery and Study Program, 4Department of Anesthesia, McMaster University, Hamilton, 5Ontario Addiction Treatment Centres, Richmond Hill, 6Department of Medicine, Hamilton General Hospital, Hamilton, 7Northern Ontario School of Medicine, Sudbury, 8Population Genomics Program, Chanchlani Research Centre, McMaster University, Hamilton, 9Centre for Evaluation of Medicine, 10System Linked Research Unit, Hamilton, 11Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada

Background: Chronic pain is the most commonly reported comorbidity among patients with opioid addiction receiving methadone maintenance treatment (MMT), with an estimated prevalence ranging between 30% and 55%. Evidence suggests that patients with comorbid pain are at high risk for poor treatment response, including continued illicit substance use. Due to the important relationship between the presence of pain and illicit substance abuse within the MMT setting, it is imperative that we target our efforts toward understanding the characteristics of this patient population.
Methods: The primary objective of this study was to explore the clinical and inflammatory profile of MMT patients reporting comorbid pain. This multicenter study enrolled patients (n=235) on MMT for the treatment of opioid dependence. Clinical history and blood and urine data were collected. Blood samples were obtained for estimating the serum levels of inflammatory markers (tumor necrosis factor [TNF]-α, interleukin-1 receptor antagonist [IL-1ra], IL-6, IL-8, IL-10, interferon [IFN]-γ and chemokine (C–C motif) ligand 2 [CCL2]). The study objectives were addressed using a descriptive statistical summary and a multivariable logistic regression model constructed in STATA version 12.
Results: Among the participants eligible for inclusion (n=235), serum IFN-γ level and substance abuse behavior proved to be important delineating characteristics for the detection of comorbid pain. Analysis of inflammatory profile showed IFN-γ to be significantly elevated among patients reporting comorbid pain (odds ratio [OR]: 2.02; 95% confidence interval [CI]: 1.17, 3.50; P=0.01). Patients reporting comorbid pain were also found to have an increase in positive opioid urine screens (OR: 1.02; 95% CI: 1.00, 1.03; P=0.01), indicating an increase in illicit opioid consumption.
Conclusion: MMT patients with comorbid pain were shown to have elevated IFN-γ and higher rates of continued opioid abuse. The ability to objectively distinguish between patients with comorbid pain may help to both improve the prediction of poor responders to MMT as well as identify treatment approaches such as anti-inflammatory medications as safe alternatives for MMT patients with comorbid pain.

Keywords: methadone maintenance treatment, inflammatory markers, TNF-α, IFN-γ, interleukins, CCL2, Brief Pain Inventory, opioid dependence

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF]  View Full Text [HTML][Machine readable]