Refractory dependence on opioid analgesics

Novel analgesic peptide derived from Cinobufacini injection suppressing inflammation and pain via ERK1/2/COX-2 pathway

Inflammatory pain is a chronic pain caused by peripheral tissue inflammation, seriously impacting the patient's life quality. Cinobufacini injection, as a traditional Chinese medicine injection preparation, shows excellent efficacy in anti-inflammatory and analgesic treatment in patients with advanced tumors. In this study, a novel analgesic peptide CI5 with anti-inflammatory and analgesic bio-functions that naturally presents in Cinobufacini injection and its regulatory mechanism are reported. Our results showed that the administration of CI5 significantly relieved the pain of mice in the acetic acid twisting analgesic model and formalin inflammatory pain model. Furthermore, CI5 effectively reduced the inflammatory cytokines (IL-6, TNF-α and IL-1β) and inflammatory mediator (PGE2) expressions, and prevented the carrageenan-induced paw edema in mice. Further LC-MS/MS results showed the anti-inflammatory and analgesic bio-functions of CI5 depended on its interaction with the Rac-2 protein upstream of ERK1/2 and the inflammatory signaling pathway (ERK1/2/COX-2 axis). In summary, CI5, as a novel natural candidate identified from Cinobufacini injection, showed substantial clinical promise for inflammatory pain treatments.

Psychological profiles and prescription opioid misuse, craving, and withdrawal in people with chronic pain

BACKGROUND

The negative consequences of prescription opioid misuse and opioid use disorder make it relevant to identify factors associated with this problem in individuals with chronic pain. This cross-sectional study aimed at identifying subgroups of people with chronic pain based on their psychological profiles, prescription opioid misuse, craving, and withdrawal.

METHODS

The sample comprised 185 individuals with chronic pain. We performed hierarchical cluster analysis on impulsivity, anxiety sensitivity, pain acceptance, pain intensity, opioid misuse, craving, and withdrawal.

RESULTS

The four-cluster solution was the optimal one. Misuse, craving, and anxiety sensitivity were higher among people in the Severe-problems cluster than among people in the other three clusters. Withdrawal was the highest in the High-withdrawal cluster. Impulsivity was higher among people in the Severe-problems and High-withdrawal clusters than those in the Moderate-problems and Mild-problems clusters. Pain acceptance was higher among people in the Mild-problems cluster than among people in the other three clusters. Anxiety sensitivity and misuse were higher among people in the Moderate-problems cluster than among people in the Mild-problems cluster.

CONCLUSIONS

These results support that impulsivity, anxiety sensitivity, and pain acceptance are useful constructs to identify subgroups of people with chronic pain according to their level of prescription opioid misuse, craving, and withdrawal. The results of this study may help in selecting the early intervention most suitable for each of the identified profiles.

SIGNIFICANCE

The psychological profile of individuals with chronic pain, prescription opioid misuse, craving, and withdrawal is characterized by fearing anxiety-related symptoms due to the catastrophic interpretation of such symptoms and reacting impulsively to negative moods. In contrast, participants with high pain acceptance had less prescription opioid misuse, craving, and withdrawal. The profiles identified in this study could help clinicians select targets for intervention among profiles with similar needs and facilitate early interventions to prevent opioid misuse onset or aggravation.

Implementation of Opioid Safety Efforts: Influence of Academic Detailing on Adverse Outcomes Among Patients in the Veterans Health Administration

BACKGROUND

The Veterans Health Administration (VA) implemented academic detailing (AD) to support safer opioid prescribing and overdose prevention initiatives.

METHODS

Patient-level data were extracted monthly from VA's electronic health record to evaluate whether AD implementation was associated with changes in all-cause mortality, opioid poisoning inpatient admissions, and opioid poisoning emergency department (ED) visits in an observational cohort of patients with long-term opioid prescriptions (≥45-day supply of opioids 6 months prior to a given month with ≤15 days between prescriptions). A single-group interrupted time series analysis using segmented logistic regression for mortality and Poisson regression for counts of inpatient admissions and ED visits was used to identify whether the level and slope of these outcomes changed in response to AD implementation.

RESULTS

Among 955 376 unique patients (19 431 241 person-months), there were 53 369 deaths (29 025 pre-AD; 24 344 post-AD), 1927 opioid poisoning inpatient admissions (610 pre-AD; 1317 post-AD), and 408 opioid poisoning ED visits (207 pre-AD; 201 post-AD). Immediately after AD implementation, there was a 5.8% reduction in the odds of all-cause mortality (95% confidence interval [CI]: 0.897, 0.990). However, patients had a significantly increased incidence rate of inpatient admissions for opioid poisoning immediately after AD implementation (incidence rate ratio = 1.523; 95% CI: 1.118, 2.077). No significant differences in ED visits for opioid poisoning were observed.

CONCLUSIONS

AD was associated with decreased all-cause mortality but increased inpatient hospitalization for opioid poisoning among patients prescribed long-term opioids. Mechanisms via which AD's efforts influenced opioid-related outcomes should be explored.

Impact of Opioid Dose Reductions on Patient-Reported Mental Health and Suicide-Related Behavior and Relationship to Patient Choice in Tapering Decisions

Mental health and suicide-related harms resulting from prescription opioid tapering are poorly documented and understood. Six health systems contributed opioid prescribing data from January 2016 to April 2020. Patients 18 to 70 years old with evidence of opioid tapering participated in semi-structured interviews. Individuals who experienced suicide attempts were oversampled. Family members of suicide decedents who had experienced opioid tapering were also interviewed. Interviews were analyzed using thematic analysis. The study participants included 176 patients and 16 family members. Patients were 68% female, 80% White, and 15% Hispanic, mean age 58. All family members were female spouses of White, non-Hispanic male decedents. Among the subgroup (n = 60) who experienced a documented suicide attempt, reported experiencing suicidal ideation during tapering, or were family members of suicide decedents, 40% reported that opioid tapering exacerbated previously recognized mental health issues, and 25% reported that tapering triggered new-onset mental health concerns. Among participants with suicide behavior, 47% directly attributed it to opioid tapering. Common precipitants included increased pain, reduced life engagement, sleep problems, withdrawal, relationship dissolution, and negative consequences of opioid substitution with other substances for pain relief. Most respondents reporting suicide behavior felt that the decision to taper was made by the health care system or a clinician (67%) whereas patients not reporting suicide behavior were more likely to report it was their own decision (42%). This study describes patient-reported mental health deterioration or suicide behavior while tapering prescription opioids. Clinicians should screen for, monitor, and treat suicide behavior while assisting patients in tapering opioids. PERSPECTIVE: This work describes changes in patient-reported mental health and suicide behavior while tapering prescription opioids. Recommendations for improving care include mental health and suicide risk screening during and following opioid tapering.

Targeting Pannexin-1 Channels: Addressing the 'Gap' in Chronic Pain

Chronic pain complicates many diseases and is notoriously difficult to treat. In search of new therapeutic targets, pannexin-1 (Panx1) channels have sparked intense interest as a key mechanism involved in a variety of chronic pain conditions. Panx1 channels are transmembrane proteins that release ions and small molecules, such as adenosine triphosphate (ATP). They are expressed along important nodes of the pain pathway, modulating activity of diverse cell types implicated in the development and progression of chronic pain caused by injury or pathology. This review highlights advances that have unlocked the core structure and machinery controlling Panx1 function with a focus on understanding and treating chronic pain.

Alcohol Use Disorder Treatment: Problems and Solutions

Alcohol use disorder (AUD) afflicts over 29 million individuals and causes more than 140,000 deaths annually in the United States. A heuristic framework for AUD includes a three-stage cycle-binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation-that provides a starting point for exploring the heterogeneity of AUD with regard to treatment. Effective behavioral health treatments and US Food and Drug Administration-approved medications are available but greatly underutilized, creating a major treatment gap. This review outlines challenges that face the alcohol field in closing this treatment gap and offers solutions, including broadening end points for the approval of medications for the treatment of AUD; increasing the uptake of screening, brief intervention, and referral to treatment; addressing stigma; implementing a heuristic definition of recovery; engaging early treatment; and educating health-care professionals and the public about challenges that are associated with alcohol misuse. Additionally, this review focuses on broadening potential targets for the development of medications for AUD by utilizing the three-stage heuristic model of addiction that outlines domains of dysfunction in AUD and the mediating neurobiology of AUD.

Opioid withdrawal: role in addiction and neural mechanisms

Withdrawal from opioids involves a negative affective state that promotes maintenance of drug-seeking behavior and relapse. As such, understanding the neurobiological mechanisms underlying withdrawal from opioid drugs is critical as scientists and clinicians seek to develop new treatments and therapies. In this review, we focus on the neural systems known to mediate the affective and somatic signs and symptoms of opioid withdrawal, including the mesolimbic dopaminergic system, basolateral amygdala, extended amygdala, and brain and hormonal stress systems. Evidence from preclinical studies suggests that these systems are altered following opioid exposure and that these changes mediate behavioral signs of negative affect such as aversion and anxiety during withdrawal. Adaptations in these systems also parallel the behavioral and psychological features of opioid use disorder (OUD), highlighting the important role of withdrawal in the development of addictive behavior. Implications for relapse and treatment are discussed as well as promising avenues for future research, with the hope of promoting continued progress toward characterizing neural contributors to opioid withdrawal and compulsive opioid use.

Opioid deprescribing in patients with chronic noncancer pain: a systematic review of international guidelines

ABSTRACT

In response to the overuse of prescription opioid analgesics, clinical practice guidelines encourage opioid deprescribing (ie, dose reduction or cessation) in patients with chronic noncancer pain. Therefore, this study evaluated and compared international clinical guideline recommendations on opioid deprescribing in patients with chronic noncancer pain. We searched PubMed, EMBASE, PEDro, National Institute for Health and Care Excellence (United Kingdom), and MAGICapp databases from inception to June 4, 2021, with no language or publication restrictions. In addition, we searched the National Guideline Clearinghouse and International Guideline Network databases from inception to December 2018. Two independent reviewers conducted the initial title and abstract screening. After discrepancies were resolved through discussion, 2 independent reviewers conducted the full-text screening of each potentially eligible reference. Four independent reviewers completed the prepiloted, standardized data extraction forms of each included guideline. Extracted information included bibliographical details; strength of recommendations; and the outcomes, such as when and how to deprescribe, managing withdrawal symptoms, additional support, outcome monitoring, and deprescribing with coprescription of sedatives. A narrative synthesis was used to present the results. This study found that clinical practice guidelines agree on when and how to deprescribe opioid analgesics but lack advice on managing a patient's withdrawal symptoms, outcome monitoring, and deprescribing with coprescription of sedatives. Quality assessment of the guidelines suggests that greater discussion on implementation and dissemination is needed.

Virtual reality distraction, a novel tool for pain alleviation during dressing change following surgical drainage of perianal abscess at Day Treatment Centre

Background

The pain induced by postoperative dressing changes adversely influence recovery and quality of life. In this study, we try to evaluate the pain alleviation effect of virtual reality (VR) distraction during postoperative dressing changes of patients who received surgical drainage of perianal abscess.

Methods

This was a prospective, randomized clinical trial. A total of 172 patients with perianal abscess were randomly assigned into control (only analgesics) and VR groups (VR distraction + analgesics). The pain and physiological measurements of all patients were collected before, during, and after the first dressing change following surgery. The difference in pain intensity and physiological parameters measurement between control and VR group was analyzed.

Results

The baseline characteristics of VR and control group were comparable (all P > 0.05). There was no significant difference in mean pain scores prior to and after dressing change between groups (both P > 0.05). Mean pain scores of 5, 10, 15, and 20 min measuring points during the first dressing change were significantly lower in the VR group compared with the control group (all P < 0.05). Pulse rates and oxygen saturation were not significantly different between groups.

Conclusion

VR can be used as an effective adjuvant pain distraction approach for postoperative dressing change.

Variation in Clinical Characteristics and Longitudinal Outcomes in Individuals with Opioid Use Disorder Diagnosis Codes

BACKGROUND

Patterns of opioid use vary, including prescribed use without aberrancy, limited aberrant use, and potential opioid use disorder (OUD). In clinical practice, similar opioid-related International Classification of Disease (ICD) codes are applied across this spectrum, limiting understanding of how groups vary by sociodemographic factors, comorbidities, and long-term risks.

OBJECTIVE

(1) Examine how Veterans assigned opioid abuse/dependence ICD codes vary at diagnosis and with respect to long-term risks. (2) Determine whether those with limited aberrant use share more similarities to likely OUD vs those using opioids as prescribed.

DESIGN

Longitudinal observational cohort study.

PARTICIPANTS

National sample of Veterans categorized as having (1) likely OUD, (2) limited aberrant opioid use, or (3) prescribed, non-aberrant use based upon enhanced medical chart review.

MAIN MEASURES

Comparison of sociodemographic and clinical factors at diagnosis and rates of age-adjusted mortality, non-fatal opioid overdose, and hospitalization after diagnosis. An exploratory machine learning analysis investigated how closely those with limited aberrant use resembled those with likely OUD.

KEY RESULTS

Veterans (n = 483) were categorized as likely OUD (62.1%), limited aberrant use (17.8%), and prescribed, non-aberrant use (20.1%). Age, proportion experiencing homelessness, chronic pain, anxiety disorders, and non-opioid substance use disorders differed by group. All-cause mortality was high (44.2 per 1000 person-years (95% CI 33.9, 56.7)). Hospitalization rates per 1000 person-years were highest in the likely OUD group (831.5 (95% CI 771.0, 895.5)), compared to limited aberrant use (739.8 (95% CI 637.1, 854.4)) and prescribed, non-aberrant use (411.9 (95% CI 342.6, 490.4). The exploratory analysis reclassified 29.1% of those with limited aberrant use as having likely OUD with high confidence.

CONCLUSIONS

Veterans assigned opioid abuse/dependence ICD codes are heterogeneous and face variable long-term risks. Limited aberrant use confers increased risk compared to no aberrant use, and some may already have OUD. Findings warrant future investigation of this understudied population.

U-PAIN cohort study among patients with chronic pain in specialised pain care: a feasibility study

OBJECTIVES

To examine acceptability of study participation and feasibility of (1) recruitment, (2) data collection and (3) outcome measures for the prospective U-PAIN cohort.

DESIGN

Internal feasibility study of a prospective cohort.

PARTICIPANTS AND SETTING

64 patients, >18 years, with chronic pain at a multidisciplinary pain centre at a university hospital in Sweden.

OUTCOME MEASURES

Acceptability of study participation was measured with a study-specific 10-item Likert scale. A score <3 was considered feasible, for the two items that assessed respondent burden a higher score indicated lesser participant burden and a score >3 was feasible. Recruitment was assessed by participation rates at baseline and retention at the 1-year follow-up, with threshold values for feasibility at 75% and 80%, respectively. Data collection and outcome measures were examined by completions rates of study procedures (90% was considered feasible), sample scores, internal consistency (α>0.70 was considered feasible), and agreement between self-reported data and data retrieved from medical records on opioid use (ICC or κ>0.60 was considered feasible).

RESULTS

Acceptability for study procedures was feasible, but participation rates were low: 25%. The retention rate at 1-year follow-up was 81% for those included in the feasibility study, that is, filling out computerised patient-reported outcome measures, and 65% for those using paper and pencil format. The completion rates for the different data collection methods ranged from 83% to 95%. Agreement between self-reported opioid use and prescribed dose and between opioid use disorder according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), and clinical International Classification of Diseases-10 (ICD-10) diagnoses for opioid dependence were almost perfect (κ=0.91 and κ=0.90, respectively).

CONCLUSIONS

This feasibility study has helped to explore and improve methods for recruitment, data collection and use of outcome measures for the U-PAIN cohort. Low participation rate and high refusal rate at baseline is a challenge that needs to be further addressed.

Diagnosing Prescription Opioid Use Disorder in Patients Using Prescribed Opioids for Chronic Pain

OBJECTIVE

The diagnostic criteria for opioid use disorder, originally developed for heroin, did not anticipate the surge in prescription opioid use and the resulting complexities in diagnosing prescription opioid use disorder (POUD), including differentiation of pain relief (therapeutic intent) from more common drug use motives, such as to get high or to cope with negative affect. The authors examined the validity of the Psychiatric Research Interview for Substance and Mental Disorders, DSM-5 opioid version, an instrument designed to make this differentiation.

METHODS

Patients (N=606) from pain clinics and inpatient substance treatment who ever received a ≥30-day opioid prescription for chronic pain were evaluated for DSM-5 POUD (i.e., withdrawal and tolerance were not considered positive if patients used opioids only as prescribed, per DSM-5 guidelines) and pain-adjusted POUD (behavioral/subjective criteria were not considered positive if pain relief [therapeutic intent] was the sole motive). Bivariate correlated-outcome regression models indicated associations of 10 validators with DSM-5 and pain-adjusted POUD measures, using mean ratios for dimensional measures and odds ratios for binary measures.

RESULTS

The prevalences of DSM-5 and pain-adjusted POUD, respectively, were 44.4% and 30.4% at the ≥2-criteria threshold and 29.5% and 25.3% at the ≥4-criteria threshold. Pain adjustment had little effect on prevalence among substance treatment patients but resulted in substantially lower prevalence among pain treatment patients. All validators had significantly stronger associations with pain-adjusted than with DSM-5 dimensional POUD measures (ratios of mean ratios, 1.22-2.31). For most validators, pain-adjusted binary POUD had larger odds ratios than DSM-5 measures.

CONCLUSIONS

Adapting POUD measures for pain relief (therapeutic intent) improved validity. Studies should investigate the clinical utility of differentiating between therapeutic and nontherapeutic intent in evaluating POUD diagnostic criteria.

Differential Experience of Interdose Withdrawal During Long-Term Opioid Therapy and its Association With Patient and Treatment Characteristics: A Latent Class Analysis in Chronic Pain Population

Opioid withdrawal is characterized by a set of physical and psychological symptoms that depend on both opioid and patient specific characteristics. The present study aims to identify different latent classes of chronic pain patients according to the type of opioid withdrawal symptoms experienced, and to analyze the relationships between the classes and demographic, opioid therapy, psychological and substance use variables. This cross-sectional descriptive study included 391 chronic pain patients on long-term opioid therapy. A Latent Class Analysis (LCA) identified 3 classes (BIC = 7051.89, entropy = .87, LRTs P < .01). The mild withdrawal class showed low probabilities of presenting physical and psychological symptoms, the moderate withdrawal class was characterized by experiencing psychological symptoms, and the severe withdrawal class stood out for high probabilities of presenting both types of symptoms. The classes differed from each other, with higher rates of moderate-severe POUD, opioid misuse, anxiety, depression, and greater pain intensity and interference in more severe withdrawal classes (P < .05). The multinomial logistic regression showed that moderate-severe POUD and anxiety were the strongest variables related to moderate (OR_POUD = 3.34, OR_Anxiety = 2.58) and severe withdrawal classes (OR_POUD = 4.26, OR_Anxiety = 5.15). Considering that POUD and anxiety were strongly related to a more severe withdrawal syndrome, the inclusion of psychological interventions in pain management seems critical in this population. PERSPECTIVE: Although interdose opioid withdrawal is common in chronic pain patients, this study shows 3 different patterns in its experience (mild, moderate, and severe withdrawal). A more severe withdrawal may result in reduced effectiveness of opioids in relieving pain and increased negative consequences, such as higher risk of POUD. Findings that could help improve chronic pain management.

Long-term prescription opioid users' risk for new-onset depression increases with frequency of use

ABSTRACT

Long-term opioid therapy (LTOT) is associated with increased risk for depression. It is not known if the frequency of opioid use during LTOT is associated with new-onset depression. We used Optum's de-identified Integrated Claims-Clinical dataset (2010-2018) to create a cohort of 5146 patients, 18 to 80 years of age, with an encounter or claims in the year before new LTOT. New LTOT was defined by >90-day opioid use after remaining opioid free for 6 months. Opioid use frequency during the first 90 days of LTOT was categorized into occasional use (<50% days covered), intermittent use (50% to <80% days covered), frequent use (80% to <90% days covered), and daily use (≥90% days covered). Propensity scores and inverse probability of exposure weighting controlled for confounding in models estimating risk for new-onset depression. Patients were on average 54.5 (SD ± 13.6) years of age, 55.7% were female, 72.5% were White, and 9.5% were African American. After controlling for confounding, daily users (hazard ratio = 1.40; 95% confidence interval: 1.14-1.73) and frequent users (hazard ratio = 1.34; 95% confidence interval: 1.05-1.71) were significantly more likely to develop new-onset depression compared with occasional users. This association remained after accounting for the contribution of post-index pain diagnoses and opioid use disorder. In LTOT, risk for new depression episodes is up to 40% greater in near-daily users compared with occasional users. Patients could reduce depression risk by avoiding opioid use on as many low pain days as possible. Repeated screening for depression during LTOT is warranted.

Arguments for and Against a New Diagnostic Entity for Patients With Chronic Pain on Long-Term Opioid Therapy for Whom Harms Outweigh Benefits

The goal of this study was to understand perspectives on whether a new diagnostic entity, distinct from Diagnostic and Statistical Manual - 5 (DSM-5) opioid use disorder (OUD), is needed for patients with chronic pain on long-term opioid therapy (LTOT) for whom the harms of continued opioid therapy outweigh the benefits. Data were collected as part of a larger Delphi study. We used rapid and thematic qualitative methods to analyze data from 51 panelists with expertise in internal medicine, psychiatry, psychology, and related fields. Three-quarters of panelists supported a new diagnostic entity; common themes included recognizing distinct experiences of patients prescribed LTOT, addressing problems with DSM-5 OUD criteria, facilitating research and improved treatment, and reducing stigma. Thirteen panelists opposed the creation of a new diagnostic entity; common themes included similarities in biological underpinnings of patients prescribed LTOT and diagnosed with OUD, belief that the continuum of OUD captured patients' experiences, finding better ways to address problems with DSM-5 OUD criteria, and concerns about stigma. While this expert panel disagreed about the need for a new diagnostic entity, there was an overall acknowledgement that the current implementation of DSM-5's OUD diagnosis is not meeting the needs of LTOT providers or patients. PERSPECTIVE: The DSM-5's OUD diagnosis may not adequately meet the needs of patients on LTOT for whom the harms of continued opioid therapy outweigh the benefits. Experts do not agree on how to address this problem; more work is needed to determine if a new diagnostic entity would be beneficial.

Is Chronic Pain a Disease?

It was not until the twentieth century that pain was considered a disease. Before that it was managed medically as a symptom. The motivations for declaring chronic pain a disease, whether of the body or of the brain, include increasing its legitimacy as clinical problem and research focus worthy of attention from healthcare and research organizations alike. But 1 problem with disease concepts is that having a disease favors medical solutions and tends to reduce patient participation. We argue that chronic pain, particularly chronic primary pain (recently designated a first tier pain diagnosis in International Diagnostic Codes 11), is a learned state that is not intransigent even if it has biological correlates. Chronic pain is sometimes a symptom, and may sometimes be its own disease. But here we question the value of a disease focus for much of chronic pain for which patient involvement is essential, and which may need a much broader societal approach than is suggested by the disease designation. PERSPECTIVE: This article examines whether designating chronic pain a disease of the body or brain is helpful or harmful to patients. Can the disease designation help advance treatment, and is it needed to achieve future therapeutic breakthrough? Or does it make patients over-reliant on medical intervention and reduce their engagement in the process of recovery?

Complex Persistent Opioid Dependence-an Opioid-induced Chronic Pain Syndrome

OPINION STATEMENT

Long-term opioid therapy (LTOT) for chronic cancer and non-cancer pain is commonly ineffective in providing its stated goal of improving function through good control of pain. Opioid tapering (slow dose reduction and/or discontinuation), the logical solution, also appears to be ineffective among many patients on LTOT as it often leads to even worse pain control and function, leaving the patients and providers managing LTOT in a clinical conundrum with little treatment choices. Complex persistent opioid dependence (CPOD) was recently offered as a heuristic to explain this clinical conundrum exemplified by the ineffectiveness of both LTOT and opioid tapering. This manuscript provides a detailed description of the neurobehavioral underpinnings of CPOD, explaining how long-term opioid use can lead to more pain even while experiencing relief with each opioid dose. CPOD is characterized by the allostatic opponent mechanisms of neuroadaptations related to the progression of opioid dependence and tolerance involving nociceptive/anti-nociceptive brain systems causing opioid-induced hyperalgesia and reward/anti-reward systems causing hyperkatefia or suffering that induces pain experience through the cognitive/emotional component of pain mechanisms. "Opioid Induced Chronic Pain syndrome" (OICP) is offered as an alternate clinical diagnostic term instead of CPOD that has several limitations as a diagnosis term including poor patient acceptance due to stigma towards addiction and clinical confounding with opioid use disorder, a related but separate clinical entity. OICP with LTOT is conceptualized as a recoverable iatrogenic problem that can be managed by pain providers. Broad guidance on management of OICP is also provided.

Patients' self-reported physical and psychological effects of opioid use in chronic noncancer pain-A retrospective cross-sectional analysis

BACKGROUND

Strong opioids can have unintended effects. Clinical studies of strong opioids mainly report physical side effects, psychiatric or opioid use disorders. To date, too little attention has been paid to the psychological effects of opioids to treat patients with chronic noncancer pain (CNCP). This study aims to identify and measure (i) the nature and frequency of physical and psychological effects and (ii) the degree of physician counseling of patients with CNCP taking strong opioids.

METHODS

Within a cross-sectional survey-conducted as part of a randomised controlled online intervention trial (ERONA [Experiencing the risk of overusing opioids among patients with chronic non-cancer pain in ambulatory care])-300 German CNCP patients were surveyed via patient-reported outcome measures regarding on both the side effects from their use of strong opioids as well as their counselling experience.

RESULTS

Among the patients' reported effects, the psychological outcomes of the opioids in CNCP were: feeling relaxed (84%), fatigue (76%), dizziness (57%), listlessness (37%), difficulty with mental activities (23%), dulled emotions (17%) and poor memory (17%). Ninety-two per cent of the patients reported having received information about opioid effects, and 46% had discussed cessation of the opioid medication with their physicians before commencing the prescription.

CONCLUSIONS

In addition to the well-known physical side effects, patients with CNCP taking strong opioids experience significant psychological effects. In view of these effects, discontinuation of opioid therapy should be discussed early to ensure their benefits do not outweigh their harm.

SIGNIFICANCE

In this study, patients with non-cancer pain notice that opioids they have taken do not only cause physical side effects but also may have an impact on their psyche and their emotions and, thus, may also affect quality of life substantially. Clinical trial number: DRKS00020358.

Evaluation of Buprenorphine Rotation in Patients Receiving Long-term Opioids for Chronic Pain: A Systematic Review

IMPORTANCE

Individuals with chronic pain who use long-term opioid therapy (LTOT) are at risk of opioid use disorder and other harmful outcomes. Rotation to buprenorphine may be considered, but the outcomes of such rotation in this population have not been systematically reviewed.

OBJECTIVE

To synthesize the evidence on rotation to buprenorphine from full μ-opioid receptor agonists among individuals with chronic pain who were receiving LTOT, including the outcomes of precipitated opioid withdrawal, pain intensity, pain interference, treatment success, adverse events or adverse effects, mental health condition, and health care use.

EVIDENCE REVIEW

PubMed, CINAHL, Embase, and PsycInfo were searched from inception through November 3, 2020, for peer-reviewed original English-language research that reported the prespecified outcomes of rotation from prescribed long-term opioids to buprenorphine among individuals with chronic pain. Two independent reviewers extracted data as well as assessed risk of bias and study quality according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Quality of evidence was assessed with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

FINDINGS

A total of 22 studies were analyzed, of which 5 (22.7%) were randomized clinical trials, 7 (31.8%) were case-control or cohort studies, and 10 (45.5%) were uncontrolled pre-post studies, which involved 1616 unique participants (675 female [41.8%] and 941 male [58.2%] individuals). Six of the 22 studies (27.3%) were primary or secondary analyses of a large randomized clinical trial. Participants had diverse pain and opioid use histories. Rationale for buprenorphine rotation included inadequate analgesia, intolerable adverse effects, risky opioid regimens (eg, high dose and/or sedative coprescriptions), and aberrant opioid use. Most protocols were adapted from protocols for initiating treatment in patients with opioid use disorder and used buccal or sublingual buprenorphine. Very low-quality evidence suggested that buprenorphine rotation was associated with maintained or improved analgesia, with a low risk of precipitating opioid withdrawal. Steady-dose buprenorphine was better tolerated than tapered-dose buprenorphine. Adverse effects were manageable, and severe adverse events were rare. Only 2 studies evaluated mental health outcomes, but none evaluated health care use. Limitations included a high risk of bias in most studies.

CONCLUSIONS AND RELEVANCE

In this systematic review, buprenorphine was associated with reduced chronic pain intensity without precipitating opioid withdrawal in individuals with chronic pain who were receiving LTOT. Future studies are necessary to ascertain the ideal starting dose, formulation, and administration frequency of buprenorphine as well as the best approach to buprenorphine rotation.

Day-to-day opioid withdrawal symptoms, psychological distress, and opioid craving in patients with chronic pain prescribed opioid therapy

BACKGROUND

Research has shown that opioid craving is one of the strongest determinants of opioid misuse in patients with chronic pain. To date, however, little is known on the factors that contribute to opioid craving in these patients. It is possible that patients' physical dependence to opioids, manifested by opioid withdrawal symptoms in between daily opioid doses, contribute to opioid craving. Physical dependence symptoms might also lead to psychological distress, which in turn might contribute to opioid craving. The first objective of this study was to examine the day-to-day association between opioid withdrawal symptoms and opioid craving among patients with chronic pain. We also examined whether negative affect and catastrophic thinking mediated this association.

METHODS

In this longitudinal study, chronic pain patients (n = 79) prescribed short-acting opioids completed daily diaries for 14 consecutive days. Diaries assessed a host of pain, psychological, and opioid-related variables.

RESULTS

Day-to-day elevations in opioid withdrawal symptoms were associated with heightened opioid craving (p < .001). Results of a multilevel mediation analysis revealed that this association was mediated by patients' daily levels of negative affect and catastrophizing (p < .001).

CONCLUSIONS

Our study provides valuable new insights into our understanding of factors that may contribute to prescription opioid craving among patients with chronic pain.

Donepezil prevents morphine tolerance by regulating N-methyl-d-aspartate receptor, protein kinase C and CaM-dependent kinase II expression in rats

Current studies have indicated that donepezil as a cholinesterase inhibitor can attenuate morphine-induced tolerance. The present study aimed to evaluate the possible role of N-methyl-d-aspartate receptors (NMDARs), protein kinase C (PKC) and CaM-dependent kinase II (CaMKII) pathways in this effect. Female Wistar rats received daily morphine (10 mg/kg, i.p.) alone or in combination with donepezil (1.5 or 2 mg/kg, gavaged) for 14 days. The analgesic effect was assessed by Von-frey, hotplate and tail flick test. On the 15th day, the periaqueductal gray (PAG) and lumbar spinal cord of rats were dissected. Then, protein levels of NMDAR-NR1, NR2B, PKCγ and CaMKIIα were tested using Western blot method. The results showed that morphine tolerance was seen after 8-10 days of injection compared with control group, while daily co-administration of donepezil with morphine prolonged the occurrence of analgesic tolerance. Western blot showed that morphine significantly increased NR1, PKCγ and CaMKIIα expressions in PAG, and significantly increased PKCγ and CaMKIIα in spinal cord. In contrast, donepezil downregulated NR1 and PKCγ in PAG, and downregulated PKCγ and CaMKIIα in spinal cord. Moreover, donepezil alone activates NR1 and NR2B in spinal cord, which needs to be further studied. Thus, the present results suggest that the attenuation effects of donepezil on morphine tolerance are possibly mediated by preventing morphine-induced upregulations in NR1, PKCγ and CaMKIIα expressions.

Is Buprenorphine Effective for Chronic Pain? A Systematic Review and Meta-analysis

OBJECTIVE

The objective was to perform a systematic review and meta-analysis of the literature on the effects of buprenorphine on chronic pain outcomes (i.e., patient-reported pain intensity) in patients with and without opioid use disorder (OUD).

DESIGN

Ovid/Medline, PubMed, Embase, and the Cochrane Library were searched for studies that explored the effectiveness (in reducing pain) of buprenorphine treatment for chronic pain patients with and without a history of OUD. Randomized controlled trials and observational studies were included in the review.

METHODS

Two separate searches were conducted to identify buprenorphine trials that included chronic pain patients either with or without OUD. Five studies used validated pain report measures and included a chronic pain population with OUD. Nine studies used validated report measures and included chronic pain patients without OUD. Meta-analysis was performed using the R, version 3.2.2, Metafor package, version 1.9-7.

RESULTS

The meta-analysis revealed that buprenorphine has a beneficial effect on pain intensity overall, with a small mean effect size in patients with comorbid chronic pain and OUD and a moderate- to large-sized effect in chronic pain patients without OUD.

CONCLUSIONS

Our results indicate that buprenorphine is modestly beneficial in reducing pain intensity in patients without OUD. Although informative, these findings should be carefully interpreted due to the small amount of data available and the variation in study designs.

European clinical practice recommendations on opioids for chronic noncancer pain - Part 2: Special situations

BACKGROUND

Opioid use for chronic non-cancer pain (CNCP) is under debate. In the absence of pan-European guidance on this issue, a position paper was commissioned by the European Pain Federation (EFIC).

METHODS

The clinical practice recommendations were developed by eight scientific societies and one patient self-help organization under the coordination of EFIC. A systematic literature search in MEDLINE (up until January 2020) was performed. Two categories of guidance are given: Evidence-based recommendations (supported by evidence from systematic reviews of randomized controlled trials or of observational studies) and Good Clinical Practice (GCP) statements (supported either by indirect evidence or by case-series, case-control studies and clinical experience). The GRADE system was applied to move from evidence to recommendations. The recommendations and GCP statements were developed by a multiprofessional task force (including nursing, service users, physicians, physiotherapy and psychology) and formal multistep procedures to reach a set of consensus recommendations. The clinical practice recommendations were reviewed by five external reviewers from North America and Europe and were also posted for public comment.

RESULTS

The European Clinical Practice Recommendations give guidance for combination with other medications, the management of frequent (e.g. nausea, constipation) and rare (e.g. hyperalgesia) side effects, for special clinical populations (e.g. children and adolescents, pregnancy) and for special situations (e.g. liver cirrhosis).

CONCLUSION

If a trial with opioids for chronic noncancer pain is conducted, detailed knowledge and experience are needed to adapt the opioid treatment to a special patient group and/or clinical situation and to manage side effects effectively.

SIGNIFICANCE

If a trial with opioids for chronic noncancer pain is conducted, detailed knowledge and experience are needed to adapt the opioid treatment to a special patient group and/or clinical situation and to manage side effects effectively. A collaboration of medical specialties and of all health care professionals is needed for some special populations and clinical situations.

Clinical and psychological factors associated with interdose opioid withdrawal in chronic pain population

BACKGROUND

The DSM-5 diagnostic criteria for Prescription Opioid-Use Disorder (POUD) have undergone some significant changes. One of the most controversial changes has been the elimination of the withdrawal symptoms criterion when opioid use is under appropriate medical supervision. For this reason, the goal of this study was to analyze factors associated with opioid withdrawal in patients with chronic non-cancer pain (CNCP).

METHODS

This cross-sectional descriptive study involved 404 patients who use prescription opioids for long-term treatment (≥90 days) of CNCP. Measures included sociodemographic and clinical characteristics, POUD, withdrawal symptoms, craving, anxiety-depressive symptoms, and pain intensity and interference.

RESULTS

Forty-seven percent (n = 193) of the sample reported moderate-severe withdrawal symptoms, which were associated with lower age, higher daily morphine dose and duration of treatment with opioids, moderate-severe POUD, use of psychotropic drugs, higher anxiety-depressive symptoms, and greater pain intensity and interference (p < .05). Binary logistic regression analysis showed that moderate-severe POUD (OR = 2.82), anxiety (OR = 2.21), depression (OR = 1.81), higher pain interference (OR = 1.05), and longer duration of treatment with opioids were the strongest factors associated with moderate-severe withdrawal symptoms (p < .05).

CONCLUSION

Psychological factors seem to play a key role in the severity of withdrawal symptoms. Since greater intensity of these symptoms increases the risk of developing POUD, knowing the factors associated with withdrawal may be useful in developing preventive psychological interventions.

Cues conditioned to withdrawal and negative reinforcement: Neglected but key motivational elements driving opioid addiction

Opioid use disorder (OUD) is a debilitating disorder that affects millions of people. Neutral cues can acquire motivational properties when paired with the positive emotional effects of drug intoxication to stimulate relapse. However, much less research has been devoted to cues that become conditioned to the aversive effects of opioid withdrawal. We argue that environmental stimuli promote motivation for opioids when cues are paired with withdrawal (conditioned withdrawal) and generate opioid consumption to terminate conditioned withdrawal (conditioned negative reinforcement). We review evidence that cues associated with pain drive opioid consumption, as patients with chronic pain may misuse opioids to escape physical and emotional pain. We highlight sex differences in withdrawal-induced stress reactivity and withdrawal cue processing and discuss neurocircuitry that may underlie withdrawal cue processing in dependent individuals. These studies highlight the importance of studying cues associated with withdrawal in dependent individuals and point to areas for exploration in OUD research.

Feasibility of patient-focused behavioral interventions to support adults experiencing chronic noncancer pain during opioid tapering: a systematic literature review

Guidelines for chronic noncancer pain prioritize behavioral treatments. In clinical practice transition from opioids to behavioral treatments is often not endorsed by patients or providers. Feasible interventions to support opioid tapering are needed, particularly in primary care. The objectives of this paper is to review the feasibility of behavioral interventions to support opioid tapering. Electronic databases (MEDLINE, Embase, PsycINFO, and CINAHL) were searched from inception to June 2019 to identify original studies reporting feasibility (consent rates; completion rates; patient-reported acceptability; integration into clinical practice; and adverse events) of opioid tapering and transition to behavioral treatments for adults experiencing chronic noncancer pain. Google scholar and contents tables of key journals were also searched. Two authors independently extracted data and assessed methodological quality using The Quality Assessment Tool for Quantitative Studies. Eleven publications met inclusion criteria, of which three were conducted in primary care. Consent rates ranged from 27% to 98% and completion rates from 6.6% to 100%. Four studies rated at least one component of patient acceptability: helpfulness from 50%-81%; satisfaction 71%-94%, and "recommend to others" 74%-91%. Three studies reported provider perspectives and two studies reported adverse events. Quality assessment indicated all 11 studies were moderate or weak, primarily due to selection bias and lack of assessor blinding. There was also considerable heterogeneity in study design. The limited available data suggest that attempts to translate opioid tapering interventions into practice are likely to encounter substantial feasibility challenges. One possible way to ameliorate this challenge may be a clear policy context, which facilitates and support opioid reduction.

Depression and Buprenorphine Treatment in Patients with Non-cancer Pain and Prescription Opioid Dependence without Comorbid Substance Use Disorders

BACKGROUND

Depression occurs in 40% of patients with prescription opioid dependence (POD). Existing studies of the association between depression and buprenorphine (BUP) treatment for POD are inconsistent and often include patients with comorbid substance use disorders (SUD). We estimated the association between depression and BUP use in patients with pain and POD and free of comorbid SUD.

METHODS

Optum® de-identified Electronic Health Record dataset from 2010 to 2018 was used to identify 5,529 patients with chronic pain, with and without depression, receiving prescription opioids and free of substance use disorder diagnoses for one year before POD diagnoses. Unadjusted and adjusted Cox proportional hazard models and negative binomial regression models were computed to estimate the association between depression and time to BUP start, number of BUP prescriptions in the year after BUP start and time to >30 day BUP gap.

RESULTS

Patients' mean age was 52.4 (SD±15.3) years, 62% were female and 84% were white and 4.9% (n=270) started BUP. Depression was not associated with BUP initiation.. Among BUP starters, depression vs. no depression, was significantly associated with receiving 29% fewer BUP prescriptions (RR=0.71; 95%CI: 0.51-0.98) and an increased risk for > 30 day gap (HR=1.76; 95%CI:1.01-3.09).

LIMITATIONS

Missing data prevented measuring BUP dose.

CONCLUSIONS

Depression is likely associated with earlier BUP treatment dropout. Depression related medication non-adherence or possible worsening of depression following BUP taper could explain results. Research is needed to determine if depression severity is associated with BUP dose trajectories and multi-year BUP retention..

Drug Addiction: Hyperkatifeia/Negative Reinforcement as a Framework for Medications Development

Compulsive drug seeking that is associated with addiction is hypothesized to follow a heuristic framework that involves three stages (binge/intoxication, withdrawal/negative affect, and preoccupation/anticipation) and three domains of dysfunction (incentive salience/pathologic habits, negative emotional states, and executive function, respectively) via changes in the basal ganglia, extended amygdala/habenula, and frontal cortex, respectively. This review focuses on neurochemical/neurocircuitry dysregulations that contribute to hyperkatifeia, defined as a greater intensity of negative emotional/motivational signs and symptoms during withdrawal from drugs of abuse in the withdrawal/negative affect stage of the addiction cycle. Hyperkatifeia provides an additional source of motivation for compulsive drug seeking via negative reinforcement. Negative reinforcement reflects an increase in the probability of a response to remove an aversive stimulus or drug seeking to remove hyperkatifeia that is augmented by genetic/epigenetic vulnerability, environmental trauma, and psychiatric comorbidity. Neurobiological targets for hyperkatifeia in addiction involve neurocircuitry of the extended amygdala and its connections via within-system neuroadaptations in dopamine, enkephalin/endorphin opioid peptide, and γ-aminobutyric acid/glutamate systems and between-system neuroadaptations in prostress corticotropin-releasing factor, norepinephrine, glucocorticoid, dynorphin, hypocretin, and neuroimmune systems and antistress neuropeptide Y, nociceptin, endocannabinoid, and oxytocin systems. Such neurochemical/neurocircuitry dysregulations are hypothesized to mediate a negative hedonic set point that gradually gains allostatic load and shifts from a homeostatic hedonic state to an allostatic hedonic state. Based on preclinical studies and translational studies to date, medications and behavioral therapies that reset brain stress, antistress, and emotional pain systems and return them to homeostasis would be promising new targets for medication development. SIGNIFICANCE STATEMENT: The focus of this review is on neurochemical/neurocircuitry dysregulations that contribute to hyperkatifeia, defined as a greater intensity of negative emotional/motivational signs and symptoms during withdrawal from drugs of abuse in the withdrawal/negative affect stage of the drug addiction cycle and a driving force for negative reinforcement in addiction. Medications and behavioral therapies that reverse hyperkatifeia by resetting brain stress, antistress, and emotional pain systems and returning them to homeostasis would be promising new targets for medication development.

When Physical and Social Pain Coexist: Insights Into Opioid Therapy

The US opioid epidemic challenges us to rethink our understanding of the function of opioids and the nature of chronic pain. We have neatly separated opioid use and abuse as well as physical and social pain in ways that may not be consistent with the most recent neuroscientific and epidemiological research. Physical injury and social rejection activate similar brain centers. Many of the patients who use opioid medications long term for the treatment of chronic pain have both physical and social pain, but these medications may produce a state of persistent opioid dependence that suppresses the endogenous opioid system that is essential for human socialization and reward processing. Recognition of the social aspects of chronic pain and opioid action can improve our treatment of chronic pain and our use of opioid medications.

Complex Persistent Opioid Dependence with Long-term Opioids: a Gray Area That Needs Definition, Better Understanding, Treatment Guidance, and Policy Changes

The multitude of treatments available for tens of millions of US adults with moderate/severe chronic pain have limited efficacy. Long-term opioid therapy (LTOT) is a widely available option for controlling pain among patients with chronic pain refractory to other treatments. The recent recognition of LTOT inefficacy and complications has led to more frequent opioid tapering, which in turn has revealed its own set of complications. The occurrence of the same set of symptoms-worsening pain, declining function, and clinical instability-in contrasting contexts of LTOT ineffectiveness and opioid tapering has led to increasing recognition of the utility of complex persistent opioid dependence (CPOD), a clinically distinct but biologically similar state compared with opioid use disorder as an explanatory diagnosis/heuristic. Recent guidelines for LTOT tapering have incorporated buprenorphine treatment based on CPOD concepts as a recommended treatment for problems due to opioid tapering with limited supportive evidence. The increasing utilization of buprenorphine for both LTOT ineffectiveness and opioid tapering problems raises the urgent need for a review of the clinical definition, mechanisms, and treatment of CPOD and pertinent policies. In this manuscript, we discuss various issues related to CPOD that requires further clarification through research and policy development.

Primary Care Clinicians' Beliefs and Strategies for Managing Chronic Pain in an Era of a National Opioid Epidemic

BACKGROUND

Little is known about how primary care clinicians (PCCs) approach chronic pain management in the current climate of rapidly changing guidelines and the growing body of research about risks and benefits of opioid therapy.

OBJECTIVE

To better understand PCCs' approaches to managing patients with chronic pain and explore implications for technological and administrative interventions.

DESIGN

We conducted adapted critical decision method interviews with 20 PCCs. Each PCC participated in 1-5 interviews.

PARTICIPANTS

PCCs interviewed had a mean of 14 years of experience. They were sampled from 13 different clinics in rural, suburban, and urban health settings across the state of Indiana.

APPROACH

Interviews included discussion of participants' general approach to managing chronic pain, as well as in-depth discussion of specific patients with chronic pain. Interviews were audio recorded. Transcripts were analyzed thematically.

KEY RESULTS

PCCs reflected on strategies they use to encourage and motivate patients. We identified four associated strategic themes: (1) developing trust, (2) eliciting information from the patient, (3) diverting attention from pain to function, and (4) articulating realistic goals for the patient. In discussion of chronic pain management, PCCs often explained their beliefs about opioid therapy. Three themes emerged: (1) Opioid use tends to reduce function, (2) Opioids are often not effective for long-term pain treatment, and (3) Response to pain and opioids is highly variable.

CONCLUSIONS

PCC beliefs about opioid therapy generally align with the clinical evidence, but may have some important gaps. These findings suggest the potential value of interventions that include improved access to research findings; organizational changes to support PCCs in spending time with patients to develop rapport and trust, elicit information about pain, and manage patient expectations; and the need for innovative clinical cognitive support.

Withdrawal-associated injury site pain prevalence and correlates among opioid-using people who inject drugs in Vancouver, Canada

BACKGROUND

Pain can return temporarily to old injury sites during opioid withdrawal. The prevalence and impact of opioid withdrawal-associated injury site pain (WISP) in various groups is unknown.

METHODS

Using data from observational cohorts, we estimated the prevalence and correlates of WISP among opioid-using people who inject drugs (PWID). Between June and December 2015, data on WISP and opioid use behaviours were elicited from participants in three ongoing prospective cohort studies in Vancouver, Canada, who were aged 18 years and older and who self-reported at least daily injection of heroin or non-medical presciption opioids.

RESULTS

Among 631 individuals, 276 (43.7 %) had a healed injury (usually pain-free), among whom 112 (40.6 %) experienced WISP, representing 17.7 % of opioid-using PWID interviewed. In a multivariable logistic regression model, WISP was positively associated with having a high school diploma or above (Adjusted Odds Ratio [AOR] = 2.23, 95 % Confidence Interval [CI]: 1.31-3.84), any heroin use in the last six months (AOR = 2.00, 95 % CI: 1.14-3.57), feeling daily pain that required medication (AOR = 2.06, CI: 1.18-3.63), and negatively associated with older age at first drug use (AOR = 0.96, 95 % CI: 0.93-0.99). Among 112 individuals with WISP, 79 (70.5 %) said that having this pain affected their opioid use behaviour, of whom 57 (72.2 %) used more opioids, 19 (24.1 %) avoided opioid withdrawal, while 3 (3.8 %) no longer used opioids to avoid WISP.

CONCLUSIONS

WISP is prevalent among PWID with a previous injury, and may alter opioid use patterns. Improved care strategies for WISP are warrented.

Ensuring Patient Protections When Tapering Opioids: Consensus Panel Recommendations

Long-term opioid therapy has the potential for serious adverse outcomes and is often used in a vulnerable population. Because adverse effects or failure to maintain benefits is common with long-term use, opioid taper or discontinuation may be indicated in certain patients. Concerns about the adverse individual and population effects of opioids have led to numerous strategies aimed at reductions in prescribing. Although opioid reduction efforts have had generally beneficial effects, there have been unintended consequences. Abrupt reduction or discontinuation has been associated with harms that include serious withdrawal symptoms, psychological distress, self-medicating with illicit substances, uncontrolled pain, and suicide. Key questions remain about when and how to safely reduce or discontinue opioids in different patient populations. Thus, health care professionals who reduce or discontinue long-term opioid therapy require a clear understanding of the associated benefits and risks as well as guidance on the best practices for safe and effective opioid reduction. An interdisciplinary panel of pain clinicians and one patient advocate formulated recommendations on tapering methods and ongoing pain management in primary care with emphasis on patient-centered, integrated, comprehensive treatment models employing a biopsychosocial perspective.

Pain management with opioids in adults

Given the ubiquitous nature of opioids in the treatment of pain, it is an interesting paradox that this class of medications also represents one of the least understood components of clinical pain medicine. For many years, there has been intense interest in the mechanisms of opioid activity, but this has not resulted in a corresponding increase in convincing clinical data. This review focuses primarily on the evidence surrounding the long-term use of opioids in chronic pain, but discussions of this research are often conflated with the very different data governing acute and cancer-related pain, where evidence of efficacy is clearer. It is therefore important to clarify the evidence-based indications for opioid therapy. There remains very little evidence that opioids improve function or quality of life beyond 3 months in people with chronic pain conditions. In all three patient populations, the development of tolerance, dependence, hyperalgesia and withdrawal are key phenomena that affect the patient experience, and in particular the decision to remain on opioids in the long term. This is a common thread that connects the opioid literature in all of these spheres, and justifies the burgeoning interest in these phenomena in the basic science literature. There is an urgent need to address these negative consequences of opioid use, in order to maximize the therapeutic benefit that opioids can offer.

Canadian Guidelines on Opioid Use Disorder Among Older Adults

BACKGROUND

In Canada, rates of hospital admission from opioid overdose are higher for older adults (≥ 65) than younger adults, and opioid use disorder (OUD) is a growing concern. In response, Health Canada commissioned the Canadian Coalition of Seniors' Mental Health to create guidelines for the prevention, screening, assessment, and treatment of OUD in older adults.

METHODS

A systematic review of English language literature from 2008-2018 regarding OUD in adults was conducted. Previously published guidelines were evaluated using AGREE II, and key guidelines updated using ADAPTE method, by drawing on current literature. Recommendations were created and assessed using the GRADE method.

RESULTS

Thirty-two recommendations were created. Prevention recommendations: it is key to prioritize non-pharmacological and non-opioid strategies to treat acute and chronic noncancer pain. Assessment recommendations: a comprehensive assessment is important to help discern contributions of other medical conditions. Treatment recommendations: buprenorphine is first line for both withdrawal management and maintenance therapy, while methadone, slow-release oral morphine, or naltrexone can be used as alternatives under certain circumstances; non-pharmacological treatments should be offered as an integrated part of care.

CONCLUSION

These guidelines provide practical and timely clinical recommendations on the prevention, assessment, and treatment of OUD in older adults within the Canadian context.