Prevalence of Problematic Use of Opioids in Patients with Chronic Noncancer Pain: A Systematic Review with Meta-analysis

Misuse, Abuse and Medication Errors' Adverse Events Associated with Opioids-A Systematic Review

Opioids are the strongest analgesics available and are crucial in the treatment of acute and chronic pain. The line between these critical medications and how they are used beyond standard therapeutics in cases such as abuse, misuse, and medication errors needs to be understood, as it affects their safety, efficacy, and manner of use. The aim of this systematic review was to identify what is known about the adverse events resulting from the abuse, misuse, and medication errors associated with opioid use. A systematic search was conducted in the PubMed®, Scopus® and, EBSCO® databases to retrieve studies from the inception to December 2023 reporting abuse, misuse, and medication errors associated with medicinal opioid use. Two authors independently screened titles and abstracts and full text according to eligibility using Covidence® software. Full articles were examined by two independent reviewers, and disagreements were resolved by a third reviewer. The risk of bias was assessed by the JBI's critical appraisal tools. A total of 934 articles were screened by their title and abstract. Then, 151 articles were selected for full text screening. Of these, 34 studies were eligible for inclusion in this review. The included studies varied significantly in their population sizes, ranging from 9 individuals to 298,433 patients, and encompassed a diverse demographic, including all ages and both sexes. The studies consistently reported a range of adverse events associated with opioid use. Fentanyl, morphine, oxycodone, tramadol, and hydrocodone were frequently implicated. The data heterogeneity in this field resulted in challenges in drawing conclusions. The review highlights that some opioids, particularly fentanyl, morphine, and oxycodone, are frequently associated with preventable adverse drug reactions, abuse, and medication errors, underscoring the need for robust preventative measures and ongoing research to mitigate opioid-related harm.

Prevalence of opioid misuse in patients with cancer: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Long-term consequences of opioid consumption, such as misuse, have been a major concern in patients with chronic non-cancer pain. Potentially opioid misuse may also be a consequence in patients with cancer in opioid treatment which encouraged us to undertake this systematic review assessing the frequency of opioid misuse in this population.

MATERIALS/METHODS

The search strategy comprised words related to cancer, opioid misuse, and frequency. PubMed, Embase, PsycInfo, and Cinahl were searched from inception to July 2023. Prospective studies were selected and analysed regarding frequency, study characteristics, and quality. A meta-analysis was possible to carry out for a sub-group (opioid misuse risk).

RESULTS

From 585 abstracts screened, six articles were included. Only prevalence data were found. The prevalence of opioid misuse ranged from 5.7% to 84%, while the prevalence of opioid misuse risk varied from 2.4% to 35.4%. The pooled prevalence of opioid misuse risk was 12.3% (95% CI: 0.8-36.3; I2 = 98.4%, 95% CI: 97.2-99.1). The studies differed regarding, e.g., methods, misuse definitions, and assessment instruments.

CONCLUSIONS

Few studies were identified and large differences in prevalence for opioid misuse and opioid misuse risk were observed. Methodological disparities and the studies quality underscore the importance of improved studies in the future.

Attentional Bias for Opioids in Taiwanese Heavy Smokers with Chronic Noncancer Pain

Background and Objectives: Attentional bias (AB) for addictive substances is a feature of attention found in individuals with substance misuse or diagnosed with substance use disorders. When AB exists, the attention of the addicted individual may be quickly oriented to cues related to the addictive substance or be maintained on these cues for a longer time. AB toward opioids was found in Western samples of smokers with chronic noncancer pain. The level of AB was dose-responsive. However, similar studies in the Taiwanese population are lacking. This study compared the patterns of AB for opioid analgesics in Taiwanese participants with chronic noncancer pain to that of individuals without pain. This study aimed to investigate if AB toward opioids is presented in Taiwanese heavy smokers who are on long-term opioid therapy for pain control. Materials and Methods: Participants were grouped into chronic noncancer pain smokers, chronic pain nonsmokers, and smokers without pain, according to smoking habits and whether or not on long-term opioid therapy for pain control. Each participant completed demographic questionnaires, mood scales, and the opioid-related visual probe task. Differences in AB among the groups were compared using a three-way analysis of covariance controlling for daily cigarette consumption. Results: Chronic noncancer pain smokers (n = 17) and chronic pain nonsmokers (n = 16) displayed more severe levels of depression, anxiety, and pain, compared to smokers without pain (n = 28). Only did chronic pain nonsmokers show significant AB for opioid cues that were displayed for a short time. Analysis on reaction time found that smokers without pain consistently responded faster to the tasks. No difference in reaction time was found between the pain groups. Conclusions: The current study did not fully replicate findings from studies that were based in Western countries. Formulary availability and regulatory limitations might have affected patient's perception of prescription opioids in Taiwan. However, chronic pain nonsmokers exhibited initial orientation toward opioid-related cues when daily cigarette consumption was accounted for. According to previous research, this AB for shortly displayed opioid cues can be associated with the expectation of pain relief. The current finding also indicated general psychomotor retardation in individuals who were on long-term use of opioids.

Clinical prediction of opioid use disorder in chronic pain patients: a cohort-retrospective study with a pharmacogenetic approach

BACKGROUND

Opioids are widely used in chronic non-cancer pain (CNCP) management. However, they remain controversial due to serious risk of causing opioid use disorder (OUD). Our main aim was to develop a predictive model for future clinical translation that include pharmacogenetic markers.

METHODS

An observational study was conducted in 806 pre-screened Spanish CNCP patients, under long-term use of opioids, to compare cases (with OUD, N.=137) with controls (without OUD, N.=669). Mu-opioid receptor 1 (OPRM1, A118G, rs1799971) and catechol-O-methyltransferase (COMT, G472A, rs4680) genetic variants plus cytochrome P450 2D6 (CYP2D6) liver enzyme phenotypes were analyzed. Socio-demographic, clinical and pharmacological outcomes were also registered. A logistic regression model was performed. The model performance and diagnostic accuracy were calculated.

RESULTS

OPRM1-AA genotype and CYP2D6 poor and ultrarapid metabolizers together with three other potential predictors: 1) age; 2) work disability; 3) oral morphine equivalent daily dose (MEDD), were selected with a satisfactory diagnostic accuracy (sensitivity: 0.82 and specificity: 0.85), goodness of fit (P=0.87) and discrimination (0.89). Cases were ten-year younger with lower incomes, more sleep disturbances, benzodiazepines use, and history of substance use disorder in front of controls.

CONCLUSIONS

Functional polymorphisms related to OPRM1 variant and CYP2D6 phenotypes may predict a higher OUD risk. Established risk factors such as young age, elevated MEDD and lower incomes were identified. A predictive model is expected to be implemented in clinical setting among CNCP patients under long-term opioids use.

Understanding the kynurenine pathway: A narrative review on its impact across chronic pain conditions

Chronic pain is a debilitating symptom with a significant negative impact on the quality of life and socioeconomic status, particularly among adults and the elderly. Major Depressive Disorder (MDD) stands out as one of the most important comorbid disorders accompanying chronic pain. The kynurenine pathway serves as the primary route for tryptophan degradation and holds critical significance in various biological processes, including the regulation of neurotransmitters, immune responses, cancer development, metabolism, and inflammation. This review encompasses key research studies related to the kynurenine pathway in the context of headache, neuropathic pain, gastrointestinal disorders, fibromyalgia, chronic fatigue syndrome, and MDD. Various metabolites produced in the kynurenine pathway, such as kynurenic acid and quinolinic acid, exhibit neuroprotective and neurotoxic effects, respectively. Recent studies have highlighted the significant involvement of kynurenine and its metabolites in the pathophysiology of pain. Moreover, pharmacological interventions targeting the regulation of the kynurenine pathway have shown therapeutic promise in pain management. Understanding the underlying mechanisms of this pathway presents an opportunity for developing personalized, innovative, and non-opioid approaches to pain treatment. Therefore, this narrative review explores the role of the kynurenine pathway in various chronic pain disorders and its association with depression and chronic pain.

Are pharmacists on the front lines of the opioid epidemic? A cross-sectional study of the practices and competencies of community and hospital pharmacists in Punjab, Pakistan

INTRODUCTION

Countries are grappling with a rapidly worsening upsurge in the opioid-related overdose deaths, misuse and abuse. There is a dearth of data in Pakistan regarding the practices and competencies of pharmacists in handling opioid-related issues.

STUDY DESIGN

A cross-sectional study, conducted across Punjab, Pakistan.

METHOD

The study deployed a validated survey to evaluate the competencies and practices of the community and hospital pharmacists.

RESULTS

504 community pharmacists and 279 hospital pharmacists participated in the survey with an overall response rate of 85.5%. Almost half of the respondents 'never' or 'sometimes' made clinical notes in a journal or dispensing software to monitor ongoing opioid use. Generally, pharmacists were reluctant to collaborate with physicians or notify police regarding the abuse/misuse of opioids. Hospital pharmacists achieved significantly higher mean competency scores than chain and independent community pharmacists (p<0.05). In competency evaluation, three priority areas emerged that require additional training, that is, 'opioid overdose management', 'opioid use monitoring' and 'therapeutic uses of opioids'.

CONCLUSION

Both community and hospital pharmacists hold significant positions and potential to contribute meaningfully to the mitigation of harms and risks associated with opioids. Nevertheless, this study underscores notable deficiencies in the competence of pharmacists, whether in hospital or community settings in Punjab, concerning various aspects related to the dispensing and utilisation of opioids. It also highlights the pressing need for the development of strategies aimed at improving several practice areas including the documentation, the quality of patient counselling, the effectiveness of reporting mechanisms for opioid abuse and the stringent enforcement of regulatory policies to curtail opioid misuse. Thus, to mitigate the opioid epidemic in Pakistan, it is imperative to institute opioid stewardship initiatives aimed at rectifying the competency and procedural deficiencies within the pharmacist workforce.

Toward a Psychological Model of Chemical Coping with Opioids in Cancer Care

LEARNING OBJECTIVES AFTER PARTICIPATING IN THIS CME ACTIVITY, THE PSYCHIATRIST SHOULD BE BETTER ABLE TO

• Outline the risk factors involved with opioid accessibility in patients receiving treatment for cancer.• Identify factors to address in order to mitigate risk for opioid misuse during cancer care.

ABSTRACT

Most patients with advanced cancer receive treatment for related pain. Opioid accessibility, however, is a risk factor for misuse, which can present care challenges and quality-of-life concerns. There is a lack of consistent universal screening prior to initiation of opioid prescribing. One crucial issue in treating this population is adequately identifying and mitigating risk factors driving opioid misuse. Drawing on theory and research from addiction science, psychology, palliative care, and oncology, the presented conceptual framework suggests that risk factors for opioid misuse during cancer care can be stratified into historical, current, malleable, and unmalleable factors. The framework identifies necessary factors to address in order to mitigate risk for opioid misuse during cancer care, and offers key directions for future research.

Oxycodone withdrawal induces HDAC1/HDAC2-dependent transcriptional maladaptations in the reward pathway in a mouse model of peripheral nerve injury

The development of physical dependence and addiction disorders due to misuse of opioid analgesics is a major concern with pain therapeutics. We developed a mouse model of oxycodone exposure and subsequent withdrawal in the presence or absence of chronic neuropathic pain. Oxycodone withdrawal alone triggered robust gene expression adaptations in the nucleus accumbens, medial prefrontal cortex and ventral tegmental area, with numerous genes and pathways selectively affected by oxycodone withdrawal in mice with peripheral nerve injury. Pathway analysis predicted that histone deacetylase (HDAC) 1 is a top upstream regulator in opioid withdrawal in nucleus accumbens and medial prefrontal cortex. The novel HDAC1/HDAC2 inhibitor, Regenacy Brain Class I HDAC Inhibitor (RBC1HI), attenuated behavioral manifestations of oxycodone withdrawal, especially in mice with neuropathic pain. These findings suggest that inhibition of HDAC1/HDAC2 may provide an avenue for patients with chronic pain who are dependent on opioids to transition to non-opioid analgesics.

Factors associated with strong opioid use for noncancer pain in patients with chronic intestinal failure

BACKGROUND

Chronic analgesic use is described in home parenteral nutrition (HPN)-dependent patients, but there are limited data on factors associated with opioid use for noncancerous pain.

METHODS

Patients attending a national UK intestinal failure reference center were divided in two groups according to strong opioid (SO) usage; risk factors for SO usage were analyzed using logistic regression.

RESULTS

A total of 168 HPN-dependent patients were included. During the study period, 73 patients (43.5%) had documented SO usage (SO group), whereas the remainder did not (No-SO group). The prevalence of Crohn's disease among the No-SO group was twofold higher than among the SO group (43.2% vs 24.7%; P = 0.013), whereas those with surgical complications were twice as prevalent among the SO group (19.2% vs 8.4%, respectively; P = 0.04). The rate of working-age unemployment was significantly higher in the SO group (90.6%) than the No-SO group (55.6%; P = 0.001). Multivariate regression showed unemployment as an independent risk factor for SO usage (OR, 6.005; 95% CI, 1.435-25.134), whereas Crohn's disease (OR, 0.284; 95% CI, 0.09-0.898) and <4 intravenous support (IVS) nights per week (OR, 0.113; 95% CI, 0.012-1.009) were protective factors. The life-long incidence of catheter-related bloodstream infection (CRBSI) was comparable between groups (34.2% SO vs 27.4% No-SO; P = 0.336).

CONCLUSION

SO use is frequent among HPN-dependent patients and associated with high rates of unemployment and ≥4 IVS nights per week, but not with increased rate of CRBSI. The reduced usage among patients with Crohn's disease warrants further evaluation but might be due to the chronicity as compared with other IF etiologies.

Logic model for opioid safety in chronic non-malignant pain management, an in-depth qualitative study

BACKGROUND

Opioids are commonly used for the management of chronic non-malignant pain in Pakistan; but there is a lack of literature around precursors or motivators in the use of opioids.

AIM

The study holistically explored factors contributing towards the unsafe use of opioids and identifies strategies to overcome them.

METHOD

Exploratory qualitative methods using interviews, focus groups and non-participant observational case studies were used. Interviews and focus groups were carried out face-to-face as well as virtually and observations were conducted in community pharmacies in Islamabad and Khyber Pukhtoon Khuwa province, Pakistan. Data were collected from 4 stakeholder groups; pharmacy policy makers (n = 11), people with chronic non-malignant pain (n = 14), doctors (n = 31) and community pharmacists (n = 36) by purposive critical case sampling method. Data were analysed inductively using reflexive thematic analysis and then deductively mapped to a social ecological framework. Non-participant observations were analysed using a cross case synthesis using explanation building technique. Data from all three methods were triangulated to develop a logic model.

RESULTS

Identified factors at macro (regulation), meso (social perceptions of pain and opioids) and micro levels (uncontrolled pain, self-medication, health literacy) and strategies are presented holistically and were used to develop a logic model for the prevention and mitigation of factors currently causing unsafe use of opioids.

CONCLUSION

The study provides an in-depth view of factors contributing towards diversion of pharmaceutical opioids and can help guide national and international policy makers in their future initiatives to promote safe use of opioids in the management of chronic non-malignant pain in Pakistan.

Endogenous opioid systems alterations in pain and opioid use disorder

Decades of research advances have established a central role for endogenous opioid systems in regulating reward processing, mood, motivation, learning and memory, gastrointestinal function, and pain relief. Endogenous opioid systems are present ubiquitously throughout the central and peripheral nervous system. They are composed of four families, namely the μ (MOPR), κ (KOPR), δ (DOPR), and nociceptin/orphanin FQ (NOPR) opioid receptors systems. These receptors signal through the action of their endogenous opioid peptides β-endorphins, dynorphins, enkephalins, and nociceptins, respectfully, to maintain homeostasis under normal physiological states. Due to their prominent role in pain regulation, exogenous opioids-primarily targeting the MOPR, have been historically used in medicine as analgesics, but their ability to produce euphoric effects also present high risks for abuse. The ability of pain and opioid use to perturb endogenous opioid system function, particularly within the central nervous system, may increase the likelihood of developing opioid use disorder (OUD). Today, the opioid crisis represents a major social, economic, and public health concern. In this review, we summarize the current state of the literature on the function, expression, pharmacology, and regulation of endogenous opioid systems in pain. Additionally, we discuss the adaptations in the endogenous opioid systems upon use of exogenous opioids which contribute to the development of OUD. Finally, we describe the intricate relationship between pain, endogenous opioid systems, and the proclivity for opioid misuse, as well as potential advances in generating safer and more efficient pain therapies.

Interprofessional Oncology Providers' Experiences and Knowledge of Opioid Use Disorders in Patients With Cancer

OBJECTIVES

To determine oncology providers' experiences and knowledge of opioid use disorders (OUDs) in patients with cancer.

SAMPLE & SETTING

The final sample of 773 participants included 42 physicians, 213 advanced practice providers (APPs), and 518 nurses at a large comprehensive cancer center.

METHODS & VARIABLES

This study used a cross-sectional descriptive survey to describe providers' experiences and knowledge of OUDs.

RESULTS

Nurses and APPs reported personal experiences with addiction and encountering issues with OUDs in patients more often compared to physicians. Knowledge deficits were identified regarding addiction, including evidence-based treatment for OUDs. Overall, OUDs are a topic of concern that the majority of oncology providers are interested in learning more about.

IMPLICATIONS FOR NURSING

The opioid epidemic presents an opportunity to improve the knowledge of interprofessional oncology providers addressing OUDs. Nurses and APPs are ideally positioned for the prevention and early recognition of patients with an OUD and cancer.

The Concept, Development, and Application of a Home-Based High-Definition tDCS for Bilateral Motor Cortex Modulation in Migraine and Pain

Whereas, many debilitating chronic pain disorders are dominantly bilateral (e.g., fibromyalgia, chronic migraine), non-invasive and invasive cortical neuromodulation therapies predominantly apply unilateral stimulation. The development of excitatory stimulation targeting bilateral primary motor (M1) cortices could potentially expand its therapeutic effect to more global pain relief. However, this is hampered by increased procedural and technical complexity. For example, repetitive transcranial magnetic stimulation (rTMS) and 4 × 1/2 × 2 high-definition transcranial direct current stimulation (4 × 1/2 × 2 HD-tDCS) are largely center-based, with unilateral-target focus-bilateral excitation would require two rTMS/4 × 1 HD-tDCS systems. We developed a system that allows for focal, non-invasive, self-applied, and simultaneous bilateral excitatory M1 stimulation, supporting long-term home-based treatment with a well-tolerated wearable battery-powered device. Here, we overviewed the most employed M1 neuromodulation methods, from invasive techniques to non-invasive TMS and tDCS. The evaluation extended from non-invasive diffuse asymmetric bilateral (M1-supraorbital [SO] tDCS), non-invasive and invasive unilateral focal (4 × 1/2 × 2 HD-tDCS, rTMS, MCS), to non-invasive and invasive bilateral bipolar (M1-M1 tDCS, MCS), before outlining our proposal for a neuromodulatory system with unique features. Computational models were applied to compare brain current flow for current laboratory-based unilateral M11 and bilateral M12 HD-tDCS models with a functional home-based M11-2 HD-tDCS prototype. We concluded the study by discussing the promising concept of bilateral excitatory M1 stimulation for more global pain relief, which is also non-invasive, focal, and home-based.