ObjectiveThe crisis of prescription opioid (PO) related harms has focused attention toward identifying and treating high-risk populations. This review aims to synthesize systematic reviews on the epidemiology and clinical management of comorbid chronic pain and PO or other substance misuse.MethodsA systematic database search was conducted to identify systematic reviews published between 2000 and 2016. Eligible studies were systematic reviews related to chronic non-cancer pain and PO or other substance misuse. Evidence from the included reviews was synthesized according to epidemiology and clinical management themes.ResultsOf 1908 identified articles, 18 systematic reviews were eligible for final inclusion. Two meta-analyses estimated the prevalence of chronic non-cancer pain in individuals using POs non-medically to be approximately 48% to 60%, which is substantially higher than the prevalence of chronic non-cancer pain in general population samples (11% to 19%). Five systematic reviews estimated the rates of PO or other opioid use in chronic pain populations with substantial variation in results (0.05% to 81%), likely due to widely varying definitions of dependence, substance use disorder, misuse, addiction, and abuse. Several clinical assessment and treatment approaches were identified, including: standardized assessment instruments; urine drug testing; medication counts; prescription drug monitoring programs; blood level monitoring; treatment agreements; opioid selection; dosing and dispensing strategies; and opioid agonist treatment. However, the reviews commonly noted serious limitations, inconsistencies, and imprecision of studies, and a lack of evidence on effectiveness or clinical utility for the majority of these strategies.ConclusionOverall, current systematic reviews have found a lack of high-quality evidence or consistent findings on the prevalence, risk factors, and optimal clinical assessment and treatment approaches related to concurrent chronic pain and substance misuse. Given the role of systematic reviews in guiding evidence-based medicine and health policy, there is an urgent need for high-quality primary research to guide future systematic reviews to address the escalating epidemic of harms related to chronic pain and substance misuse.Electronic supplementary materialThe online version of this article (doi:10.1186/s13011-017-0120-7) contains supplementary material, which is available to authorized users.

Introduction and Aims Despite the high prevalence of pain among people who inject drugs (PWID), clinicians may be reluctant to prescribe opioid-based analgesia to those with a history of drug use or addiction. We sought to examine the prevalence and correlates of PWID reporting being denied prescription analgesia (PA). We also explored reported reasons for and actions taken after being denied PA. Design and Methods Using data from two prospective cohort studies of PWID in Vancouver, Canada, multivariate logistic regression was used to identify the prevalence and correlates of reporting being denied PA. Descriptive statistics were used to characterize reasons for denials and subsequent actions. Results Approximately two thirds (66.5%) of our sample of 462 active PWID reported having ever been denied PA. We found that reporting being denied PA was significantly and positively associated with having ever been enrolled in methadone maintenance treatment (MMT) (adjusted odds ratio [AOR]=1.76, 95%CI: 1.11–2.80) and daily cocaine injection (AOR=2.38, 95%CI: 1.00–5.66). The most commonly reported reason for being denied PA was being accused of drug-seeking (44.0%). Commonly reported actions taken after being denied PA included buying the requested medication off the street (40.1%) or obtaining heroin to treat pain (32.9%) Discussion and Conclusions These findings highlight the clinical challenges of addressing perceived pain control needs and the need for strategies to prevent high-risk methods of self-managing pain, such as obtaining diverted medications or illicit substances for pain. Such strategies may include integrated pain management guidelines within MMT and other substance use treatment programs.

The complexity of treating concurrent pain and opioid dependence among many methadone-maintained individuals presents a major challenge in many clinical settings. Furthermore, recent expert guidelines have called for increased research on the safety of methadone in the context of chronic pain. This study explores the prevalence and correlates of pain among a prospective cohort of people who use illicit drugs in Vancouver, Canada, who reported enrollment in methadone maintenance treatment (MMT) between 2011 and 2014. Among the 823 participants eligible for this analysis, 338 (40.9%) reported moderate pain and 91 (11.1%) reported extreme pain at the first study visit. In multivariable generalized linear mixed model analyses, higher pain severity was positively and independently associated with self-managing pain (adjusted odds ratio [AOR]=2.15, 95% confidence interval [CI]=1.77–2.60), patient perception of methadone dose being “too low” (AOR=1.82, 95% CI=1.41–2.34), older age (AOR=1.31, 95% CI=1.13–1.51), having a physical disability (AOR=4.59, 95% CI=3.73–5.64), having ever been diagnosed with a mental illness (AOR=1.44, 95% CI=1.13–1.84), Caucasian ethnicity (AOR=1.42, 95% CI=1.10–1.83), and marijuana use (AOR=1.25, 95% CI=1.02–1.52). These findings suggest several areas for clinical intervention, particularly related to patient education and alternative analgesic approaches for MMT patients experiencing pain.

People who use illicit drugs are at risk for related health complications, and may rely more heavily on emergency departments and acute care centres for their health care needs. Health care workers may be hesitant to prescribe pain medication to these individuals due to fear of addiction and suspicion of drug-seeking behaviour. Accordingly, the aim of this study was to assess the relationship between having ever been denied pain medication and having reported using illicit drugs in a Vancouver (British Columbia) cohort of illicit drug users.

SUMMARY Aims To evaluate factors and methods associated with self-management of pain among people who inject drugs (IDUs) in Vancouver (Canada). Patients & methods This cross-sectional study used bivariate statistics and multivariate logistic regression to analyze self-reported responses among 483 IDUs reporting moderate-to-extreme pain in two prospective cohort studies from 1 December 2012 to 31 May 2013. Results Median age was 49.6 years (interquartile range: 43.9–54.6 years), 33.1% of IDUs were female and 97.5% reported self-management of pain. Variables independently and positively associated with self-managed pain included having been refused a prescription for pain medication (adjusted odds ratio: 7.83; 95% CI: 1.64–37.3) and having ever been homeless (adjusted odds ratio: 3.70; 95% CI: 1.00–13.7). Common methods of self-management of pain included injecting heroin (52.7%) and obtaining diverted prescription pain medication from the street (65.0%). Conclusion Self-management of pain was common among IDUs who reported moderate-to-extreme pain in this setting, particularly among those who had been refused a prescription for pain medication and those who had ever been homeless. These data highlight the challenges of adequate pain management among IDUs.

Nearly four years after the United States Congress heralded a “decade of pain control and research”, chronic pain remains a mounting public health concern worldwide. The escalating prevalence of chronic pain in recent years has been paralleled by a rise in prescription opioid availability, misuse, and associated human and social costs. However, national monitoring surveys in the U.S. and Canada currently fail to differentiate between prescription opioid misuse for the purposes of euphoria versus pain or withdrawal management. Furthermore, there is a lack of evidence-based guidelines for pain management among high-risk individuals, and a glaring lack of education for practitioners in the areas of pain and addiction medicine. Herein we propose multiple avenues for intervention and research in order to mitigate the individual, social and structural problems related to undertreated pain and prescription opioid misuse.

Background Although many people who inject drugs (PID) contend with comorbidities, including high rates of mental illness, limited attention has been given to the differences in comorbidities among men and women or the potential links between psychiatric disorders and HIV risk behaviours. We sought to longitudinally examine associations between depression and HIV-related sexual risk behaviours among PID, stratified by gender. Methods Data were derived from a prospective cohort of PID in Vancouver, Canada between December 2005 and November 2009. Using generalised estimating equations, we examined the relationship between depressive symptoms and two types of sexual HIV risk behaviours: engaging in unprotected sex; and having multiple sexual partners. All analyses were stratified by self-reported gender. Results Overall, 1017 PID participated in this study, including 331 (32.5%) women. At baseline, women reported significantly higher depressive symptoms than men (P < 0.001). In multivariate generalised estimating equations analyses, after adjustment for potential social, demographic and behavioural confounders, more severe depressive symptomology remained independently associated with engaging in unprotected sex [adjusted odds ratio (AOR) = 1.62, 95% confidence interval (CI): 1.18 – 2.23] and having multiple sexual partners (AOR = 1.54, 95% CI: 1.09 – 2.19) among women, but was only marginally associated with having multiple sexual partners among men (AOR = 1.18, 95% CI: 0.98 – 1.41). Conclusions These findings call for improved integration of psychiatric screening and treatment services within existing public health initiatives designed for PID, particularly for women. Efforts are also needed to address sexual risk-taking among female PID contending with clinically significant depression.

BackgroundPeople who use drugs have a significantly higher prevalence of chronic non-cancer pain compared to the general population, yet little is known about how various policy, economic, physical, and social environments may serve as risk or protective factors in the context of concurrent pain and substance use. Therefore, this study sought to explore perspectives, risks, and harms associated with pain among people who use drugs.MethodsThirteen focus group interviews were held across British Columbia, Canada, from July to September 2015. In total, 83 people who had lived experience with substance use participated in the study. Using an interpretive description approach, themes were conceptualized according to the Rhodes’ Risk Environment and patient-centered care frameworks.ResultsParticipants described how their experiences with inadequately managed pain in various policy, economic, physical, and social environments reinforced marginalization, such as restrictive policies, economic vulnerability, lack of access to socio-physical support systems, stigma from health professionals, and denial of pain medication leading to risky self-medication. Principles of patient-centered care were often not upheld, from a lack of recognition of patients as experts in understanding their unique pain needs and experiences, to an absence of shared power and decision-making, which often resulted in distrust of the patient-provider relationship.ConclusionsVarious risk environments and non-patient-centered interactions may contribute to an array of health and social harms in the context of inadequately managed pain among people who use drugs.