Topical Review on the Abuse and Misuse Potential of Tramadol and Tilidine in Germany

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.

Tramadol use before total shoulder arthroplasty: patients have lower risk of complications and resource utilization than those using traditional opioids

BACKGROUND

Evidence continues to mount for the deleterious effects of preoperative opioid use in the setting of total shoulder arthroplasty (TSA). Tramadol, a synthetic opioid with concomitant neurotransmitter effects, has become a popular alternative to traditional opioids, but it has not been well studied in the preoperative setting of TSA. The purpose of this study is to evaluate postsurgical outcomes in TSA for patients with preoperative tramadol use compared with patients using traditional opioids and those who were opioid naïve.

METHODS

Using the IBM Watson Health MarketScan databases, a retrospective cohort study was performed for patients who underwent TSA from 2009 to 2018. Filled pain prescriptions were collected, and prescribing trends were analyzed. Outcomes were compared between 4 patient cohorts defined by preoperative analgesia use-opioid naïve, tramadol, traditional opioids, and combination (opioids and tramadol). Multivariate analysis was used to account for small variations in cohort demographics and comorbidities. Analysis focused on resource utilization and complications. Revision rates at 1 and 3 years postoperatively were also compared.

RESULTS

A total of 29,454 TSA patients were studied, with 8959 available for 3-year postoperative follow-up. Of these, 10,462 (35.5%) were prescribed traditional opioids and 2214 (7.5%) tramadol only. From 2009 to 2018, prescribing trends in the United States demonstrated a significant decrease in the number of patients prescribed preoperative narcotics, whereas the number of patients prescribed preoperative tramadol and those who were opioid naïve significantly increased. Compared with opioid-naïve patients, the traditional opioid cohort had significantly increased odds of resource utilization and complications, whereas the tramadol cohort did not. Specifically, the traditional opioid cohort had an increased risk of prosthetic joint infection compared with both opioid-naïve and tramadol cohorts. The traditional opioid cohort had higher revision rates than opioid-naïve patients at 1 and 3 years, whereas the tramadol cohort did not.

CONCLUSION

Despite a decrease in opioid prescriptions over the study period, many patients in the United States remain on opioids. Although tramadol is not without its own risks, our results suggest that patients taking preoperative tramadol as an alternative to traditional opioids for glenohumeral arthritic pain had a lesser postoperative risk profile, comparable with opioid-naïve patients.

Surgical opioid-avoidance protocol: a postoperative pharmacological multimodal analgesic intervention in diverse patient populations

INTRODUCTION

This study evaluated the effect of a surgical opioid-avoidance protocol (SOAP) on postoperative pain scores. The primary goal was to demonstrate that the SOAP was as effective as the pre-existing non-SOAP (without opioid restriction) protocol by measuring postoperative pain in a diverse, opioid-naive patient population undergoing inpatient surgery across multiple surgical services.

METHODS

This prospective cohort study was divided into SOAP and non-SOAP groups based on surgery date. The non-SOAP group had no opioid restrictions (n=382), while the SOAP group (n=449) used a rigorous, opioid-avoidance order set with patient and staff education regarding multimodal analgesia. A non-inferiority analysis assessed the SOAP impact on postoperative pain scores.

RESULTS

Postoperative pain scores in the SOAP group compared with the non-SOAP group were non-inferior (95% CI: -0.58, 0.10; non-inferiority margin=-1). The SOAP group consumed fewer postoperative opioids (median=0.67 (IQR=15) vs 8.17 morphine milliequivalents (MMEs) (IQR=40.33); p<0.01) and had fewer discharge prescription opioids (median=0 (IQR=60) vs 86.4 MMEs (IQR=140.4); p<0.01).

DISCUSSION

The SOAP was as effective as the non-SOAP group in postoperative pain scores across a diverse patient population and associated with lower postoperative opioid consumption and discharge prescription opioids.

Tramadol for chronic pain in adults: protocol for a systematic review with meta-analysis and trial sequential analysis of randomised clinical trials

BACKGROUND

Chronic pain in adults is a frequent clinical symptom with a significant impact on patient well-being. Therefore, sufficient pain management is of utmost importance. While tramadol is a commonly used pain medication, the quality of evidence supporting its use has been questioned considering the observed adverse events. Our objective will be to assess the benefits and harms of tramadol compared with placebo or no intervention for chronic pain.

METHODS/DESIGN

We will conduct a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis to assess the beneficial and harmful effects of tramadol in any dose, formulation, or duration. We will accept placebo or no intervention as control interventions. We will include adult participants with any type of chronic pain, including cancer-related pain. We will systematically search the Cochrane Library, MEDLINE, EMBASE, Science Citation Index, and BIOSIS for relevant literature. We will follow the recommendations by Cochrane and the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. The risk of systematic errors ('bias') and random errors ('play of chance') will be assessed. The certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

DISCUSSION

Although tramadol is often being used to manage chronic pain conditions, the beneficial and harmful effects of this intervention are unknown. The present review will systematically assess the current evidence on the benefits and harms of tramadol versus placebo or no intervention to inform clinical practice and future research.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019140334.

The role of lateral habenula NMDA receptors in tramadol-induced conditioning

The role of the lateral habenula (LHb) as a hub for receiving and relaying signals from the limbic system to serotonergic, dopaminergic, and norepinephrinergic regions in the brainstem makes this area a critical region in the control of reward and addiction. Behavioral evidence reveals the vital role of the LHb in negative symptoms during withdrawal. In this investigation, we study the role of the LHb N-Methyl D-Aspartate receptor (NMDAR) in the modulation of tramadol reward. Male adult Wistar rats were used in this study. The effect of intra-LHb micro-injection of NMDAR agonist (NMDA, 0.1, 0.5, 2 µg/rat) and antagonist (D-AP5, 0.1, 0.5, 1 µg/rat) was evaluated in conditioned place preference (CPP) paradigm. The obtained results showed that intra-LHb administration of NMDA induced place aversion dose-dependently, while blockade of NMDAR in the LHb using D-AP5 micro-injection led to an increased preference score in the CPP task. Co-administration of NMDA (0.5 µg/rat) with tramadol (4 mg/kg) reduced preference score, while co-administration of D-AP5 (0.5 µg/rat) with a non-effective dose of tramadol (1 mg/kg) potentiate the rewarding effect of tramadol. LHb receives inputs from the limbic system and projects to the monoaminergic nuclei in the brainstem. It has been declared that NMDAR is expressed in LHb, and as obtained data revealed, these receptors could modulate the rewarding effect of tramadol. Therefore, NMDA receptors in the LHb might be a new target for modulating tramadol abuse.

Enhanced Recovery After Aesthetic Breast Surgery Under Sedation, Intercostal Block and Tumescent Anaesthesia: A Prospective Cohort Study of the Early Postoperative Phase

BACKGROUND

Comfort and recovery are major concerns of patients seeking aesthetic surgery. This study aimed to assess postoperative pain and recovery after outpatient breast surgery under sedation, intercostal block, and local anaesthesia.

METHODS

This prospective cohort study included all consecutive patients who underwent aesthetic breast surgery between April 2021 and August 2022. Epidemiological data, anaesthesia, pain, and patients' satisfaction were systematically assessed with standardized self-assessment questionnaires.

RESULTS

Altogether, 48 patients [median (IQR) age: 30 (36-25)] were included. The most frequent surgery was mastopexy. 69% of surgeries involved additional procedures. The mean intercostal block and local anaesthesia time was 15 min. Patients received a median (IQR) of 19 (34-2) mg/kg lidocaine and 2.3 (2.5-2.0) mg/kg ropivacaine. The median (IQR) consumption of propofol and alfentanil was, respectively, 4.89 (5.48-4.26) mg/kg/h and 0.27 (0.39-0.19) µg/kg/min. No conversion to general anaesthesia or unplanned hospital admission occurred. Patients were discharged after a median (IQR) of 2:40 (3:43-1:58) hours. Within the first 24 postoperative hours, 17% required once an antiemetic medication and 38% an opioid. Patients were very satisfied with the anaesthesia and 90% of the patients had not wished more analgesia in the first 24 h.

CONCLUSIONS

Aesthetic breast surgery under sedation, intercostal block, and tumescent anaesthesia can safely be performed as an ambulatory procedure and is associated with minimal intra- and postoperative opioid consumption and high patient satisfaction. These data may be used to inform patients and clinicians and improve the overall quality of care.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Glutamatergic systems in neuropathic pain and emerging non-opioid therapies

Neuropathic pain, a disease of the somatosensory nervous system, afflicts many individuals and adequate management with current pharmacotherapies remains elusive. The glutamatergic system of neurons, receptors and transporters are intimately involved in pain but, to date, there have been few drugs developed that therapeutically modulate this system. Glutamate transporters, or excitatory amino acid transporters (EAATs), remove excess glutamate around pain transmitting neurons to decrease nociception suggesting that the modulation of glutamate transporters may represent a novel approach to the treatment of pain. This review highlights and summarizes (1) the physiology of the glutamatergic system in neuropathic pain, (2) the preclinical evidence for dysregulation of glutamate transport in animal pain models, and (3) emerging novel therapies that modulate glutamate transporters. Successful drug discovery requires continuous focus on basic and translational methods to fully elucidate the etiologies of this disease to enable the development of targeted therapies. Increasing the efficacy of astrocytic EAATs may serve as a new way to successfully treat those suffering from this devastating disease.

Short-term mortality following tramadol poisonings in Denmark

Tramadol is a commonly used opioid with a potential of addiction and abuse. Using Danish nationwide registers, we aimed to (1) characterise opioid poisonings; (2) assess the 30-day mortality following morphine, oxycodone, and mixed poisonings compared to tramadol poisonings; and (3) assess the development in tramadol poisonings during a 12-year period. Poisonings were identified from 2006 to 2017. A Cox proportional hazards regression model was used to estimate adjusted hazard ratios (aHRs) along with 95% confidence intervals (CIs) for 30-day mortality following morphine, oxycodone or mixed poisonings compared to tramadol poisonings. We identified 7718 opioid poisonings among 6365 patients. The patients with a tramadol poisoning were younger and had less comorbidities than the patients with a morphine, oxycodone or mixed poisoning. Within 30 days, a total of 205 patients died. The 30-day mortality risk was higher following morphine (aHR 3.2, 95% CI 2.0-5.1), oxycodone (aHR 2.1, 95% CI 1.2-3.6) and mixed poisonings (aHR 1.6, 95% CI 1.0-2.7) compared to tramadol poisonings. The annual number of tramadol poisonings increased from 233 in 2006 to 501 in 2013 and declined to 348 in 2017. In conclusion, despite a lower mortality risk compared to other opioid poisonings, physicians should consider the poisoning and abuse risks when prescribing tramadol.

A case of fatal multidrug intoxication involving flualprazolam: distribution in body fluids and solid tissues

Purpose

Designer benzodiazepines (DBZDs) increasingly emerged on the novel psychoactive substance (NPS) market in the last few years. They are usually sold as readily available alternatives to prescription benzodiazepines (BZDs) or added to counterfeit medicines. BZDs are generally considered relatively safe drugs due to the low risk of serious acute adverse effects in mono-intoxication, though e.g., alprazolam seems to display an elevated risk of respiratory depression. Here we report on a fatal intoxication involving the novel DBZD flualprazolam.

Methods

A complete postmortem examination was performed. General unknown screenings and analysis of drugs of abuse were performed on postmortem samples by immunoassay, gas chromatography–mass spectrometry and liquid chromatography–mass spectrometry. The standard addition method was employed to quantify flualprazolam in postmortem blood and tissues. Finally, a toxicological significance score (TSS) was assigned.

Results

Flualprazolam was detected in heart serum (25.4 ng/mL) and peripheral blood (21.9 ng/mL) as well as in urine, stomach contents, brain, liver and kidney (65.2–323 ng/g). The cause of death was deemed as central nervous system (CNS) and respiratory depression with agonal aspiration of stomach contents, in the setting of a multiple drug intake. Given the concentration levels of the co-consumed CNS depressants, the contribution of flualprazolam to the death was considered likely (TSS of 3).

Conclusions

Our results support that highly potent DBZDs like flualprazolam carry an elevated risk for unintended toxicity, especially in association with other CNS depressants. A multidisciplinary evaluation of fatalities remains mandatory, especially when pharmacological/toxicological data on intoxicating compounds are lacking. To our knowledge this is the first report of flualprazolam concentrations in solid tissues in human.

Opioid painkiller dependence in a sample of elderly medical inpatients

BACKGROUND

Over the past few years, there has been a growing concern about prescription opioid misuse and dependence in the elderly. Our study aimed to investigate the prevalence of previous and current prescription opioid dependence among elderly medical inpatients recruited from a large German hospital.

METHODS

This cross-sectional study analyzed a cohort of inpatients aged 65 years and older who were assessed with a structured clinical interview. Levels of past and current dependence on opioids benzodiazepines, hypnotics, and non-opioid analgesics were assessed.

RESULTS

Of 2108 elderly inpatients admitted to the hospital during a 6-month period, 400 fulfilled the inclusion criteria and agreed to participate to the survey. Among these 400 subjects, 43 (10.8%) presented with a dependence on opioid analgesics, including 41 with current dependence and 22 (51.2%) with a de novo condition. Addiction severity was considered mild in 65.1% of cases and severe in 11.6% of cases. Tilidine and oxycodone were the most typically reported molecules.

CONCLUSIONS

Further research is warranted, to better understand the possible risk factors of prescription drug misuse, abuse, and addiction in this vulnerable population. Clinicians should be updated and informed regarding both prescription medication misuse potential and safe prescribing practices in the elderly.

Opioid Use Associated With Higher Costs Among Patients With Inflammatory Bowel Disease

Background

Opioid use by patients with inflammatory bowel disease (IBD) has been associated with poorer health outcomes. This study describes socioeconomic characteristics; health utilization trends; and costs of patients with IBD and either no opioid prescriptions, or in 1 of 3 opioid duration categories based on Center for Disease Control guidelines: acute (0-30 days), moderate (31-90 days), or chronic (>90 days). We utilized the Cost of IBD Care Optum research database results for this study.

Methods

The Optum Research Database from years 2007 to 2016 including IBD patients with commercial or Medicare Advantage insurance in the United States was used. Additional inclusion criteria included continuous enrollment with medical and pharmacy benefit coverage for at least 24 months (12 months before and 12 months after the index date of IBD diagnosis). The association between costs and patient characteristics were assessed across a no opioid use group during this period and the 3 opioid duration groups.

Results

Among 51,178 IBD patients, 33,229 (64.93%) were part of the no opioid use group, while 13,635 (26.64%) were in acute, 1698 (3.32%) were in moderate, and 2616 (5.11%) were in chronic use groups, as determined by pharmacy claims data. Patients in the chronic group were more likely to be white (75.38%) compared to all the other groups (no opioid use, acute, and moderate), have attained less education (only high school diploma), have had lower incomes, and have had Medicare instead of commercial insurance. Patients across all opioid prescription groups were more likely to have had diagnoses associated with pain in the prior year, with rates increasing by the length of opioid prescription (63.68%, 80.17%, and 86.11% for acute, moderate, and chronic groups). Compared to the no-use group, the acute group had more ambulatory (outpatient) visits, while the chronic group had fewer. Emergency department visits and inpatient hospitalizations were higher in all 3 opioid groups compared to the no opioid use group. Ambulatory, emergency department, inpatient, and total (medical + pharmacy) costs were higher in all 3 opioid groups, compared to the no opioid use group, even after adjusting for demographic and clinical patient characteristics.

Conclusions

Among patients with IBD, increasing opioid use was associated with higher healthcare resource utilization and, concomitantly, higher healthcare costs during this period.

Postoperative opioid administration characteristics associated with opioid-induced respiratory depression: Results from the PRODIGY trial

STUDY OBJECTIVE

Opioid administration for pain in general care floor patients remains common, and can lead to adverse outcomes, including respiratory compromise. The PRODIGY trial found that among ward patients receiving parenteral opioids, 46% experienced ≥1 respiratory depression episode. The objective of this analysis was to evaluate the geographic differences of opioid administration and examine the association between opioid administration characteristics and the occurrence of respiratory depression.

DESIGN

Prospective observational trial.

SETTING

16 general care medical and surgical wards in Asia, Europe, and the United States.

PATIENTS

1335 patients receiving parenteral opioids.

INTERVENTIONS

Blinded, alarm-silenced continuous capnography and pulse oximetry monitoring.

MEASUREMENTS

Opioid-induced respiratory depression, defined as respiratory rate ≤ 5 bpm, SpO₂ ≤ 85%, or ETCO₂ ≤ 15 or ≥ 60 mmHg for ≥3 min; apnea episode lasting >30 s; or any respiratory opioid-related adverse event.

RESULTS

Across all patients, 58% received only long-acting opioids, 16% received only short-acting (<3 h) opioids, and 21% received a combination of short- and long-acting (≥3 h) opioids. The type and median total morphine milligram equivalent (MME) of opioid administered varied significantly by region, with 31.5 (12.5-76.7) MME, 31.0 (6.2-99.0) MME, and 7.2 (1.7-18.7) MME in the United States, Europe, and Asia, respectively (p < 0.001). Considering only postoperative opioids, 54% (N = 119/220) and 45% (N = 347/779) of patients receiving only short-acting opioids or only long-acting opioids experienced ≥1 episode of opioid-induced respiratory depression, respectively. Multivariable analysis identified post-procedure tramadol (OR 0.62, 95% CI 0.424-0.905, p = 0.0133) and post-procedure epidural opioids (OR 0.485, 95% CI 0.322-0.731, p = 0.0005) being associated with a significant reduction in opioid-induced respiratory depression.

CONCLUSIONS

Despite varying opioid administration characteristics between Asia, Europe, and the United States, opioid-induced respiratory depression remains a common global problem on general care medical and surgical wards. While the use of post-procedure tramadol or post-procedure epidural opioids may reduce the incidence of respiratory depression, continuous monitoring is also necessary to ensure patient safety when receiving postoperative opioids. REGISTRATION NUMBER: www.clinicaltrials.gov, ID: NCT02811302.

Preoperative Analgesia, Complications, and Resource Utilization After Total Hip Arthroplasty: Tramadol Is Associated With Less Risk Than Other Preoperative Opioid Medications

BACKGROUND

Preoperative opioid use is known to be detrimental to outcomes after total hip arthroplasty (THA). This is concerning as multiple societies recommend tramadol for the management of arthritis. The purpose of this study was to determine if tramadol is associated with postoperative complications, increased resource utilization, and revision when compared with patients receiving nontramadol opioids (NTOs) and those who are opioid naive (ON).

METHODS

This is a retrospective cohort study using the Truven MarketScan databases (Truven Health, Ann Arbor, MI). Adult patients undergoing primary THA were identified and divided into 4 cohorts based on preoperative opioid medications (ie, ON, tramadol-only [TO], or NTOs; ±tramadol). Demographics, comorbidities, and 90-day complications were collected and compared between cohorts. Revision rates were compared at 3 years. Univariate and multivariate analyses were performed. Finally, preoperative prescription patterns were trended during the study period.

RESULTS

About 198,357 patients, including 18,694 TO and 106,768 ON, were identified. Compared with ON, TO patients had similar rates of complications and revision surgery (P > .05) but had slightly higher emergency department visits (odds ratio [OR], 1.06; 95% confidence interval [95% CI], 1.01-1.12; P = .027), readmissions (OR, 1.16; 95% CI, 1.09-1.22; P < .001), and nonhome discharges (OR, 1.07; 95% CI, 1.02-1.12; P = .010). TO patients had significantly lower odds of incurring most examined complications, including revision surgery, when compared with NTO (P < .05). From 2009 to 2018, the proportion of patients prescribed preoperative opioids decreased.

CONCLUSION

Preoperative TO is associated with less postoperative risk than NTO use and is similar to opioid naivety. Fortunately, the number of patients receiving preoperative NTOs appears to be decreasing. Our results support tramadol as an appropriate pre-THA analgesic.

The impact of preoperative tramadol-only use on outcomes following total knee arthroplasty - Is tramadol different than traditional opioids?

BACKGROUND

Opioid use prior to total knee arthroplasty (TKA) is known to have detrimental influence on postoperative outcomes. Whether or not the same is true for tramadol is currently unclear. The aim of this study was to clarify the relationship between preoperative tramadol and postoperative complications.

METHODS

The Truven Marketscan® Databases were used to conduct this retrospective cohort study. Patients undergoing primary TKA were identified and divided into cohorts based on preoperative medication status (i.e. opioid naïve, tramadol-only, or non-tramadol opioids). Patient demographics, comorbidities, and 90-day outcomes were collected and compared between cohorts. Revision rates were analyzed at 1- and 3-years postoperatively. Univariate and multivariate analysis was performed.

RESULTS

336,316 patients were included and 23,097 (6.9%) were preoperative tramadol-only users. Tramadol-only patients (v. opioid naïve) had increased odds of 90-day readmission (OR-1.07, 95%CI 1.02-1.12, p = 0.004), wound complication (OR-1.13, 95%CI 1.01-1.27, p = 0.34), and 3-year revision rates (OR-1.35, 95%CI 1.19-1.53, p < 0.001). However, when compared to the preoperative opioid cohorts, tramadol-only patients had decreased odds of nearly all outcomes. Over the study period, the number of patients receiving preoperative opioids decreased while the proportion of patients prescribed tramadol-only increased.

CONCLUSIONS

While tramadol-only use has lower risk than traditional opioids, tramadol-only use preceding TKA is associated with increased rates of readmission, wound complication and revision surgery. This is important information for prescribers who may be using tramadol to treat symptomatic knee arthrosis prior to arthroplasty referral and for thought leaders producing clinical practice guidelines.

LEVEL OF EVIDENCE

Level III, Prognostic.

Opioid-Induced Respiratory Depression in Pediatric Palliative Care Patients with Severe Neurological Impairment-A Scoping Literature Review and Case Reports

Pediatric Palliative Care (PPC) addresses children, adolescents, and young adults with a broad spectrum of underlying diseases. A substantial proportion of these patients have irreversible conditions accompanied by Severe Neurological Impairment (SNI). For the treatment of pain and dyspnea, strong opioids are widely used in PPC. Nonetheless, there is considerable uncertainty regarding the opioid-related side effects in pediatric patients with SNI, particularly concerning Opioid-Induced Respiratory Depression (OIRD). Research on pain and OIRD in pediatric patients with SNI is limited. Using scoping review methodology, we performed a systematic literature search for OIRD in pediatric patients with SNI. Out of n = 521 identified articles, n = 6 studies were included in the review. Most studies examined the effects of short-term intravenous opioid therapy. The incidence of OIRD varied between 0.13% and 4.6%; besides SNI, comorbidities, and polypharmacy were the most relevant risk factors. Additionally, three clinical cases of OIRD in PPC patients receiving oral or transdermal opioids are presented and discussed. The case reports indicate that the risk factors identified in the scoping review also apply to adolescents and young adults with SNI receiving low-dose oral or transdermal opioid therapy. However, the risk of OIRD should never be a barrier to adequate symptom relief. We recommend careful consideration and systematic observation of opioid therapy in this population of patients.

Regional Differences in Opioid Prescribing in Germany - Results of an Analysis of Health Insurance Data of 57 Million Adult People

Background

Regional variations of opioid use have been reported from many countries. The objective of this study was to examine opioid prescribing patterns in Germany including low- and high-potency opioids (LPO and HPO) focusing on regional differences.

Methods

Data source was the "Information system for health care data" comprising statutory health insurance funds data for about 70 million Germans of all ages. For 2010, we received aggregated data (by age, sex, federal state and district) of Germans (18+) who had been prescribed at least one opioid including the number of prescribed packages. For each stratum, we further received the number of insured persons. We calculated LPO and HPO prevalences and the mean number of prescribed packages.

Results

Among 57 million adult Germans (mean age: 50.2 years, 53.8% female), opioid prevalences were 38.7 per 1000 persons for LPOs and 12.8 for HPOs. Prevalences rose with increasing age and were higher in women than in men. On average, LPO users were prescribed fewer packages than HPO users (3.5 vs 7.0). LPO use was highest in the eastern states ranging from 32.9 per 1000 persons (Hamburg) to 47.2 (Saxony-Anhalt). HPOs were most often prescribed in the North and in the East with prevalences varying between 10.6 per 1000 persons (Baden-Württemberg) and 16.9 (Mecklenburg-Western Pomerania). On the district level, prevalences varied by the factors 2.6 and 3.2 for LPOs and HPOs, respectively.

Conclusion

We found large regional variations in opioid prescribing which probably cannot only be attributed to differences in patient characteristics.

Preclinical assessment of tramadol abuse potential: Effects of acute and repeated tramadol on intracranial self-stimulation in rats

BACKGROUND

Tramadol is a widely used analgesic that activates mu-opioid receptors (MOR) and inhibits serotonin and norepinephrine transporters. This mixed pharmacology may limit both its own abuse potential and its modulation of abuse potential of other MOR agonists.

AIMS

This study used an intracranial self-stimulation (ICSS) procedure to compare abuse-related effects produced by acute or repeated treatment with tramadol or morphine in rats. Abuse potential in ICSS procedures is indicated by a drug-induced increase (or 'facilitation') of ICSS responding.

METHODS

Adult male Sprague-Dawley rats were implanted with electrodes targeting the medial forebrain bundle and trained to respond on a lever for pulses of electrical brain stimulation. Tramadol effects were evaluated after acute administration (3.2-32 mg/kg) in the absence or presence of the opioid antagonist naltrexone, the CYP2D6 hepatic-enzyme inhibitor quinine or a combination of both. Additionally, both tramadol and morphine were also tested before and after repeated tramadol (32 mg/kg/day for six days) or repeated morphine (3.2 mg/kg/day for six days).

RESULTS

Acute tramadol produced primarily ICSS rate-decreasing effects that were antagonised by naltrexone but not by quinine or naltrexone + quinine. Tramadol also produced little or no ICSS facilitation after repeated tramadol or repeated morphine, and repeated tramadol did not enhance ICSS facilitation by morphine. By contrast, morphine-induced ICSS facilitation was enhanced by repeated morphine treatment.

CONCLUSIONS

These results suggest that tramadol has lower abuse potential than other abused MOR agonists and that repeated tramadol exposure produces relatively little enhancement of abuse potential of other MOR agonists.

Rate of opioid use disorder in adults who received prescription opioid pain therapy-A secondary data analysis

Background and aims

Data on rates of prescription opioid use disorder (pOUD) in European countries is limited. The aim of this investigation was to analyze a representative population sample regarding the 1-year prevalence of opioid use disorder in patients who received prescription opioid pain therapy and to identify related risk factors.

Design

Cross-sectional secondary data analysis

Setting

Secondary data analysis based on data from the 2015 Epidemiological Survey of Substance Abuse (ESA 2015) in Germany

Participants

German-speaking individuals living in private households aged 18 to 64 years were investigated. A total of 9204 individuals participated in the survey, resulting in a response rate of 52.2%.

Primary and secondary outcome measures

Primary outcome measure was the weighted prevalence of pOUD in the subgroup of study participants who had received prescription opioids. Secondary outcome measure was an analysis of risk factors connected with pOUD in the same subgroup.

Findings

A total of n = 9204 participants were included in the study of which n = 275 had received an opioid prescription in the last 12 months of which n = 54 were diagnosed with pOUD. The weighted 1-year prevalence of pOUD was 21.2% (mild: 14.7% | moderate: 3.5% | severe: 2.9%). Participants who had received opioid pain therapy had significantly higher odds of pOUD if they reported signs of depression (OR: 2.69; CI 95%: 1.13–6.38), inexplicable physical complaints (OR: 2.68; CI 95%: 1.14–6.31) or a psychiatric diagnosis (OR: 4.12; CI 95%: 1.36–12.43), and significantly lower odds of pOUD if they reported the use of non-opioid painkillers (OR: 0.27; CI 95%: 0.09–0.81).

Conclusions

pOUD is a common phenomenon in working-age patients who receive prescription opioid pain therapy in Germany and may be related to the co-existence of psychosomatic and psychiatric disorders such as depression.

Achieving Opioid-Free Major Colorectal Surgery: Is It Possible?

INTRODUCTION

Opioid analgesia remains the mainstay of postoperative pain management strategies despite being associated with many adverse effects. A specific opioid-free protocol was designed to limit opioid usage.

OBJECTIVE

The aim of the study was to audit the opioid-free rate within this protocol and to identify factors that might contribute to opioid-free surgery.

METHODS

A retrospective study of all elective patients receiving abdominal colorectal surgery at the Center for Colon and Rectal Surgery at AdventHealth over 6 months was performed. Data on demographics, indications, perioperative management, outcomes, and inpatient and outpatient analgesic requirements were collected with subsequent analysis.

RESULTS

A total of 303 consecutive patient records were analyzed. Approximately two-thirds (67.7%) of patients did not receive narcotics once they left the postanesthesia care unit as an inpatient. One-third of patients (32.0%) did not receive narcotic analgesia within 30 days of surgery as an outpatient. Patients in the opioid-free cohort were significantly older and had a malignant indication, less perioperative morbidity, and a shorter length of stay.

CONCLUSIONS

Our study demonstrates that opioid-free analgesia is indeed possible in major colorectal surgery. Study limitations include its retrospective nature and that it is from a single institution. Despite these limitations, this study provides proof of concept that opioid-free colorectal surgery is possible within a specific protocol.

The utility of adding symptoms and signs to the management of injury-related pain

OBJECTIVE

Improved pain assessment and management in the emergency department (ED) is warranted. We aimed to determine the impact on pain management, of adding symptoms and signs to pain assessment.

PATIENTS AND METHODS

A single center before-and-after study was conducted, supplemented by an interrupted time series analysis. The intervention included the addition of clinical presentation (CP) of the injury and facial expression (FE) of the patient to pain assessment scales of patients with soft tissue injures. Pain intensity was categorized as: mild, moderate, and severe. We compared types of pain relief medications, use of strong opioids, and pain relief efficacy between pre and post intervention phases.

RESULTS

Before-and-after analysis revealed a significant reduction in the use of strong opioids. The adjusted relative ratio for the use of strong opioids in the post intervention phase was 0.63 (95% CI: 0.48-0.82). This reduction was mostly driven by less use of strong opioids in patients reporting severe pain (from 17.3%-7.9%) (P < 0.0001). A larger proportion of patients in the post intervention phase than in the pre intervention phase received weak opioids and nonsteroidal anti-inflammatory drugs (NSAIDs) (27.4% vs 19.1%, P = 0.002), and a larger proportion did not receive any pain relief medication (19.8% vs 10.5%, p < 0.0001). The use of strong opioids increased with higher levels of FE and CP. Among patients with mild injury and reporting severe pain, the odds of receiving a strong opioid was nearly 9 times (OR = 8.9, 95% CI: 4.0-19.6) higher among those who were with an unrelaxed FE and showed pain behavior than those with relaxed FE. Interrupted time-series analysis showed that the mean ΔVAS (VAS score at entry minus VAS score at discharge) in the post intervention phase compared with the pre intervention phase was not statistically significant (P = 0.073). The use of strong opioids in the post intervention phase was significantly reduced (P = 0.017).

CONCLUSION

Adding symptoms and signs to pain assessment of patients admitted with soft tissue injuries decreased the use of strong opioids, without affecting pain relief efficacy.

Facilitators to the continuous abuse of tramadol among the youth: A qualitative study in Northern Ghana

STUDY AIM

Considering the alarming rate at which young people abuse tramadol, as evidenced by the numerous media reports on the subject, this qualitative study was conducted to explore the facilitators to the abuse of tramadol by young people.

DESIGN AND METHODS

A qualitative exploratory descriptive design was employed in conducting the study. A total of 18 participants were purposively sampled. Data for the study were collected through two focused group discussions and three in-depth-interviews. Thematic analysis was used to analyse the data.

RESULTS

The findings of the study revealed four main themes. These themes were initiating factors of abuse; desirable physical effects; desirable psychological effects; and undesirable effects. It was revealed that many young people initially get into tramadol abuse because of peer pressure, curiosity or post-traumatic addiction. However, they often continue the practice for various physical and psychological gratifications including euphoria, attentiveness, high energy levels, pain relief and improved sexual performance. The study also revealed some unpleasant side effects of tramadol abuse such as severe vomiting, loss of appetite, seizures, emotional aloofness and irritability. Many of the participants in this study also expressed willingness to quit tramadol abuse because of social discrimination and the enormous side effects that come with the abuse of the drug.

The Use of Opioids for Treatment of Pediatric Neuropathic Pain: A Literature Review

Pediatric neuropathic pain is caused by a spectrum of disorders that are generally challenging to treat. Many of the underlying altered neurological processes are being elucidated through mechanistic studies. Few randomized control trials have evaluated the use of opioids for the treatment of adult neuropathic pain conditions, and there have been none in pediatric populations. With sparse data to provide guidance and an incomplete understanding of the underlying mechanisms, the use of opioids remains unclear. Our clinical experience and typical risk versus benefit considerations suggest a limited, if any, role for using opioids to treat pediatric neuropathic pain. In this literature review, we review the available adult and pediatric data and provide general guidance on this subject matter.

Opioid use disorder in chronic non-cancer pain in Germany: a cross sectional study

OBJECTIVES

The DSM-5 diagnosis 'opioid use disorder' (OUD) was established to better describe and detect significant impairment or distress related to opioid use. There is no data on rates of OUD in chronic non-cancer pain (CNCP) in European countries. Therefore, our objective was to screen patients in specialised pain centres for signs of OUD.

DESIGN

Cross-sectional questionnaire study.

SETTING

Four outpatient pain clinics in the area of Bonn, Germany.

PARTICIPANTS

n=204 patients participated in the study (response rate: 87.9%). All adult patients with opioid pain therapy >6 months for CNCP were included. Excluded were patients with malignant disease, patients who could not collect their prescription themselves due to age or multimorbidity and patients on opioid-maintenance therapy.

PRIMARY AND SECONDARY OUTCOME MEASURE

Primary outcome measure was the proportion of patients with mild to severe OUD.

RESULTS

One-fourth (26.5%) of participants were diagnosed with OUD. Moderate to severe disorder was found in 9.3. Young age was the only connected risk factor (OR 0.96 [95% CI 0.94 to 0.99], p: 0.003).

CONCLUSIONS

OUD is a relevant diagnosis in patients on long-term opioid therapy for CNCP in the Bonn area. Careful follow-up by the attending physicians is advisable, especially in patients with moderate or severe disorder.

Disinfection by-Products and Ecotoxic Risk Associated with Hypochlorite Treatment of Tramadol

In recent years, many studies have highlighted the consistent finding of tramadol (TRA) in the effluents from wastewater treatment plants (WTPs) and also in some rivers and lakes in both Europe and North America, suggesting that TRA is removed by no more than 36% by specific disinfection treatments. The extensive use of this drug has led to environmental pollution of both water and soil, up to its detection in growing plants. In order to expand the knowledge about TRA toxicity as well as the nature of its disinfection by-products (DBPs), a simulation of the waste treatment chlorination step has been reported herein. In particular, we found seven new by-products, that together with TRA, have been assayed on different living organisms (Aliivibrio fischeri, Raphidocelis subcapitata and Daphnia magna), to test their acute and chronic toxicity. The results reported that TRA may be classified as a harmful compound to some aquatic organisms whereas its chlorinated product mixture showed no effects on any of the organisms tested. All data suggest however that TRA chlorination treatment produces a variety of DBPs which can be more harmful than TRA and a risk for the aquatic environment and human health.

Tramadol induces changes in Δ-FosB, µ-opioid receptor, and p-CREB level in the nucleus accumbens and prefrontal cortex of male Wistar rat

BACKGROUND

Besides the analgesic effect of tramadol, prolonged exposure to tramadol can induce adaptive changes thereby leading to dependence and tolerance. Tramadol induces its effect via µ-opioid receptor (MOR). However, tramadol has other targets such as serotonin and epinephrine transporters.

OBJECTIVE

CREB and ΔFosB are transcriptional factors, which are involved in the behavioral abnormalities underlying drug abuse. In this study, the effects of acute and chronic tramadol treatments on MOR, ΔFosB, and CREB levels were studied.

METHODS

For this purpose, 36 male Wistar rats were used. The animals were divided into two main groups. A total of 18 animals received tramadol (0, 5, and 10 mg/kg) acutely and 18 animals received the same doses for the following 14 days. One hour after the last injection, the NAC and PFC were dissected and kept at -80°C in liquid nitrogen. Using western blotting technique, the levels of MOR, ΔFosB, and p-CREB were evaluated.

RESULTS

In the NAC, acute tramadol exposure increases the levels of MOR and p-CREB. Moreover, chronic tramadol administration in this region results in elevated levels of MOR, ΔFosB and p-CREB compared with saline-treated rats. The levels of MOR and p-CREB in the PFC increased in both acute and chronic tramadol exposure. Also, ΔFosB levels increased only following chronic tramadol administration. The results revealed that adaptive changes occurred during drug exposure.

CONCLUSION

We concluded that both CREB and ΔFosB played a role in tramadol dependence. Additionally, increased MOR levels during tramadol treatments might be due to receptor desensitization.

A Systematic Review of Laboratory Evidence for the Abuse Potential of Tramadol in Humans

Background: Tramadol is an opioid-analgesic that has shown epidemiological evidence of abuse. This review evaluates the evidence for tramadol abuse potential in humans. Methods: A systematic literature search for human abuse liability examinations of tramadol was conducted in September 2018 and yielded 13 total studies. Studies were all within-subject, double-blind, placebo-controlled human laboratory comparisons of tramadol to opioid comparators. Results are organized based upon the route of tramadol administration (oral, parenteral) and the participant population (persons with and without current opioid physical dependence). Outcomes were categorized into self-report ratings of positive and negative effects, observer-ratings of effects, time course of effects, likelihood tramadol was identified as an opioid, and tramadol self-administration. Results: Results indicated the relative abuse potential of tramadol was lower than the opioids to which it was compared. Tramadol produced highest positive effect ratings when administered orally to persons with no opioid physical dependence. Relative to other opioids, it produced substantial negative ratings, generally demonstrated a slower onset of effects, and was less likely to be identified by participants as an opioid, though it did produce a higher rate of self-administration relative to other opioids in the one study reporting that outcome. Results suggest that the abuse potential of tramadol is highest when it is administered orally to non-dependent individuals, and that it likely decreases as the dose increased and when it was administered parentally or to persons with opioid physical dependence. Conclusion: Taken together, individuals may be less likely than with other opioids to escalate tramadol doses, transition from oral to parenteral routes of administration, or continue using tramadol once opioid physical dependence develops. In that way, the human abuse potential of tramadol appears to be different from and lower than other opioid analgesic medications.

Effect of transcutaneous electrical acupoint stimulation on postoperative analgesia after ureteroscopic lithotripsy: a randomized controlled trial

Transcutaneous electrical acupoint stimulation (TEAS) is an effective analgesic measure. We studied the analgesic effect of TEAS by applying it alone after ureteroscopic lithotripsy, rather than applying it as a supplementary analgesic measure. Participants (n = 120) scheduled to undergo ureteroscopic holmium laser lithotripsy, were enrolled and randomly assigned into Group T (TEAS n = 60) and Group C (Control, n = 60). The participants in Group T were treated with TEAS for postoperative analgesia. TEAS were implemented on bilateral Shenyu (BL23) and Yinlingquan (SP9) at the time backward and the time at 4, 8, 12 h postoperatively. TEAS was re-implemented three times on the target acupoints for the next 2 days. When TEAS failed to meet the analgesic effect, the participants were given tramadol hydrochloride tablets of 100 mg. Participants of Group C were given tramadol hydrochloride tablets for postoperative analgesia. The primary outcome of VAS scores at the time backward (T₀), 4 h (T₁), 12 h (T₂), 24 h (T₃), 48 h (T₄) postoperatively and the amount of remedy for analgesic consumption within 48 h postoperatively were compared. The secondary outcome of adverse reactions and plasma concentrations of serotonin (5-HT) and substance P (SP) at T₀, T₁, T₂, T₃, T₄ were detected, respectively. The VAS scores at T₁, T₂, T₃, T₄ postoperatively in two groups were lower than T₀. Compared to group C, the VAS scores at T₁ (3.68 ± 0.68 vs. 4.79 ± 0.82, P = 0.01), T₂ (2.64 ± 0.72 vs. 3.92 ± 0.88, P = 0.03), T₃ (2.21 ± 0.88 vs. 3.38 ± 0.74, P < 0.01) in Group T were lower, and total remedy of analgesic consumption was significantly lower (127.14 ± 28.46 vs. 415.27 ± 86.37, P < 0.01) within 48 h postoperatively. The plasma concentrations of 5-HT in Group T was lower than Group C at T₁ (348.54 ± 138.49 vs. 418.69 ± 124.68, P = 0.03), T₂ (324.28 ± 112.73 vs. 398.52 ± 114.53, P < 0.01), T₄ (309.64 ± 129.09 vs. 388.46 ± 115.36, P = 0.04) postoperatively and concentrations of SP at T₁ (59.38 ± 24.68 vs. 78.93 ± 26.32, P < 0.01), T₂ (49.36 ± 25.55 vs. 66.49 ± 23.57, P = 0.02), T₃ (42.19 ± 24.36 vs. 64.15 ± 28.16, P = 0.04), T₄ (39.26 ± 19.88 vs. 54.64 ± 20.62, P = 0.02) postoperatively were also lower than Group C. Meanwhile, the occurrences of vertigo (6.7 vs. 18.3%, P < 0.01), nausea and vomiting (11.7 vs. 21.7%, P < 0.01), constipation (10.0 vs. 20.0%, P = 0.03) in Group T were also lower. Application of TEAS alone was associated with effective alleviation of postoperative pain, reduction of postoperative analgesics consumption, decrease of plasma concentration of algogenic substance and the incidence of adverse reactions after ureteroscopic lithotripsy.

Deaths from Opioid Overdosing: Implications of Coroners' Inquest Reports 2008-2012 and Annual Rise in Opioid Prescription Rates: A Population-Based Cohort Study

INTRODUCTION

In the late 1990s multiple physicians and advocacy organizations promoted increased use of opioids for the treatment of acute, chronic and cancer pain. There has been an exponential growth in opioid prescribing in the last 20 years in the United States of America, in Australia, and in other developed Western countries. There are negative consequences associated with the liberal use of opioids. The primary aim of this population-based cohort study is to investigate the opioid-related death rate in New Zealand between 1 January 2008 and 31 December 2012. The secondary aims of this cohort study are: (1) to compare the opioid-related death rate per population in New Zealand in 2001/2002 with that between 2011/2012; (2) to investigate the number of opioid prescriptions in New Zealand between 2001 and 2012; (3) to compare the opioid-related death rate per population in New Zealand between 2001 and 2012 with the number of opioid prescriptions in New Zealand between 2001 and 2012.

METHODS

Permission to access records from the Coronial Services Office in Wellington for 2008-2012 was acquired. Permission to access records for prescriptions containing opioids (dose and formulation) was obtained from the Pharmaceutical Collection.

RESULTS

The rate of opioid-related deaths in New Zealand has increased by 33% from 2001 to 2012. More than half of the opioid-related deaths between 2008 and 2012 were unintentional opioid overdoses. Opioid analgesic deaths were most likely due to methadone, morphine and codeine prescribed by healthcare professionals. That 179 of these opioid-related deaths between 2008 and 2012 were unintentional opioid overdoses, and thus could have been avoided, is tragic. This study shows that there was a steady annual increases in opioid prescriptions in New Zealand from 2001 to 2012. This rise in opioid analgesic deaths was associated with the increases in the numbers of opioid prescriptions.

CONCLUSION

A multifaceted national public health approach is needed to bring together the various stakeholders involved with pain management, opioid dependence, opioid availability and opioid diversion. There needs to be a targeted approach to educate current and future medical practitioners regarding the appropriate use of opioid prescriptions for the management of pain, as well as a strengthening of primary, secondary and tertiary resources to support medical practitioners managing their patients who suffer with pain.

Adverse events associated with medium- and long-term use of opioids for chronic non-cancer pain: an overview of Cochrane Reviews

BACKGROUND

Chronic pain is common and can be challenging to manage. Despite increased utilisation of opioids, the safety and efficacy of long-term use of these compounds for chronic non-cancer pain (CNCP) remains controversial. This overview of Cochrane Reviews complements the overview entitled 'High-dose opioids for chronic non-cancer pain: an overview of Cochrane Reviews'.

OBJECTIVES

To provide an overview of the occurrence and nature of adverse events associated with any opioid agent (any dose, frequency, or route of administration) used on a medium- or long-term basis for the treatment of CNCP in adults.

METHODS

We searched the Cochrane Database of Systematic Reviews (the Cochrane Library) Issue 3, 2017 on 8 March 2017 to identify all Cochrane Reviews of studies of medium- or long-term opioid use (2 weeks or more) for CNCP in adults aged 18 and over. We assessed the quality of the reviews using the AMSTAR criteria (Assessing the Methodological Quality of Systematic Reviews) as adapted for Cochrane Overviews. We assessed the quality of the evidence for the outcomes using the GRADE framework.

MAIN RESULTS

We included a total of 16 reviews in our overview, of which 14 presented unique quantitative data. These 14 Cochrane Reviews investigated 14 different opioid agents that were administered for time periods of two weeks or longer. The longest study was 13 months in duration, with most in the 6- to 16-week range. The quality of the included reviews was high using AMSTAR criteria, with 11 reviews meeting all 10 criteria, and 5 of the reviews meeting 9 out of 10, not scoring a point for either duplicate study selection and data extraction, or searching for articles irrespective of language and publication type. The quality of the evidence for the generic adverse event outcomes according to GRADE ranged from very low to moderate, with risk of bias and imprecision being identified for the following generic adverse event outcomes: any adverse event, any serious adverse event, and withdrawals due to adverse events. A GRADE assessment of the quality of the evidence for specific adverse events led to a downgrading to very low- to moderate-quality evidence due to risk of bias, indirectness, and imprecision.We calculated the equivalent milligrams of morphine per 24 hours for each opioid studied (buprenorphine, codeine, dextropropoxyphene, dihydrocodeine, fentanyl, hydromorphone, levorphanol, methadone, morphine, oxycodone, oxymorphone, tapentadol, tilidine, and tramadol). In the 14 Cochrane Reviews providing unique quantitative data, there were 61 studies with a total of 18,679 randomised participants; 12 of these studies had a cross-over design with two to four arms and a total of 796 participants. Based on the 14 selected Cochrane Reviews, there was a significantly increased risk of experiencing any adverse event with opioids compared to placebo (risk ratio (RR) 1.42, 95% confidence interval (CI) 1.22 to 1.66) as well as with opioids compared to a non-opioid active pharmacological comparator, with a similar risk ratio (RR 1.21, 95% CI 1.10 to 1.33). There was also a significantly increased risk of experiencing a serious adverse event with opioids compared to placebo (RR 2.75, 95% CI 2.06 to 3.67). Furthermore, we found significantly increased risk ratios with opioids compared to placebo for a number of specific adverse events: constipation, dizziness, drowsiness, fatigue, hot flushes, increased sweating, nausea, pruritus, and vomiting.There was no data on any of the following prespecified adverse events of interest in any of the included reviews in this overview of Cochrane Reviews: addiction, cognitive dysfunction, depressive symptoms or mood disturbances, hypogonadism or other endocrine dysfunction, respiratory depression, sexual dysfunction, and sleep apnoea or sleep-disordered breathing. We found no data for adverse events analysed by sex or ethnicity.

AUTHORS' CONCLUSIONS

A number of adverse events, including serious adverse events, are associated with the medium- and long-term use of opioids for CNCP. The absolute event rate for any adverse event with opioids in trials using a placebo as comparison was 78%, with an absolute event rate of 7.5% for any serious adverse event. Based on the adverse events identified, clinically relevant benefit would need to be clearly demonstrated before long-term use could be considered in people with CNCP in clinical practice. A number of adverse events that we would have expected to occur with opioid use were not reported in the included Cochrane Reviews. Going forward, we recommend more rigorous identification and reporting of all adverse events in randomised controlled trials and systematic reviews on opioid therapy. The absence of data for many adverse events represents a serious limitation of the evidence on opioids. We also recommend extending study follow-up, as a latency of onset may exist for some adverse events.

Tramadol for neuropathic pain in adults

BACKGROUND

This review is an update of a review of tramadol for neuropathic pain, published in 2006; updating was to bring the review in line with current standards. Neuropathic pain, which is caused by a lesion or disease affecting the somatosensory system, may be central or peripheral in origin. Peripheral neuropathic pain often includes symptoms such as burning or shooting sensations, abnormal sensitivity to normally painless stimuli, or an increased sensitivity to normally painful stimuli. Neuropathic pain is a common symptom in many diseases of the peripheral nervous system.

OBJECTIVES

To assess the analgesic efficacy of tramadol compared with placebo or other active interventions for chronic neuropathic pain in adults, and the adverse events associated with its use in clinical trials.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and Embase for randomised controlled trials from inception to January 2017. We also searched the reference lists of retrieved studies and reviews, and online clinical trial registries.

SELECTION CRITERIA

We included randomised, double-blind trials of two weeks' duration or longer, comparing tramadol (any route of administration) with placebo or another active treatment for neuropathic pain, with subjective pain assessment by the participant.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed trial quality and potential bias. Primary outcomes were participants with substantial pain relief (at least 50% pain relief over baseline or very much improved on Patient Global Impression of Change scale (PGIC)), or moderate pain relief (at least 30% pain relief over baseline or much or very much improved on PGIC). Where pooled analysis was possible, we used dichotomous data to calculate risk ratio (RR) and number needed to treat for an additional beneficial outcome (NNT) or harmful outcome (NNH), using standard methods. We assessed the quality of the evidence using GRADE and created 'Summary of findings' tables.

MAIN RESULTS

We identified six randomised, double-blind studies involving 438 participants with suitably characterised neuropathic pain. In each, tramadol was started at a dose of about 100 mg daily and increased over one to two weeks to a maximum of 400 mg daily or the maximum tolerated dose, and then maintained for the remainder of the study. Participants had experienced moderate or severe neuropathic pain for at least three months due to cancer, cancer treatment, postherpetic neuralgia, peripheral diabetic neuropathy, spinal cord injury, or polyneuropathy. The mean age was 50 to 67 years with approximately equal numbers of men and women. Exclusions were typically people with other significant comorbidity or pain from other causes. Study duration for treatments was four to six weeks, and two studies had a cross-over design.Not all studies reported all the outcomes of interest, and there were limited data for pain outcomes. At least 50% pain intensity reduction was reported in three studies (265 participants, 110 events). Using a random-effects analysis, 70/132 (53%) had at least 50% pain relief with tramadol, and 40/133 (30%) with placebo; the risk ratio (RR) was 2.2 (95% confidence interval (CI) 1.02 to 4.6). The NNT calculated from these data was 4.4 (95% CI 2.9 to 8.8). We downgraded the evidence for this outcome by two levels to low quality because of the small size of studies and of the pooled data set, because there were only 110 actual events, the analysis included different types of neuropathic pain, the studies all had at least one high risk of potential bias, and because of the limited duration of the studies.Participants experienced more adverse events with tramadol than placebo. Report of any adverse event was higher with tramadol (58%) than placebo (34%) (4 studies, 266 participants, 123 events; RR 1.6 (95% CI 1.2 to 2.1); NNH 4.2 (95% CI 2.8 to 8.3)). Adverse event withdrawal was higher with tramadol (16%) than placebo (3%) (6 studies, 485 participants, 45 events; RR 4.1 (95% CI 2.0 to 8.4); NNH 8.2 (95% CI 5.8 to 14)). Only four serious adverse events were reported, without obvious attribution to treatment, and no deaths were reported. We downgraded the evidence for this outcome by two or three levels to low or very low quality because of small study size, because there were few actual events, and because of the limited duration of the studies.

AUTHORS' CONCLUSIONS

There is only modest information about the use of tramadol in neuropathic pain, coming from small, largely inadequate studies with potential risk of bias. That bias would normally increase the apparent benefits of tramadol. The evidence of benefit from tramadol was of low or very low quality, meaning that it does not provide a reliable indication of the likely effect, and the likelihood is very high that the effect will be substantially different from the estimate in this systematic review.

Tramadol with or without paracetamol (acetaminophen) for cancer pain

BACKGROUND

Tramadol is an opioid analgesic licensed for use in moderate to severe pain. It is considered as a low risk for abuse, so control regulations are not as stringent as for 'strong' opioids such as morphine. It has a potential role as a step 2 option of the World Health Organization (WHO) analgesic ladder.

OBJECTIVES

To assess the benefits and adverse effects of tramadol with or without paracetamol (acetaminophen) for cancer-related pain.

SEARCH METHODS

We searched the following databases using a wide range of search terms: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and LILACS. We also searched three clinical trials registry databases. The date of the last search was 2 November 2016.

SELECTION CRITERIA

We selected studies that were randomised, with placebo or active controls, or both, and included a minimum of 10 participants per treatment arm. We were interested particularly in blinded studies, but also included open studies.We excluded non-randomised studies, studies of experimental pain, case reports, and clinical observations.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data using a standard form and checked for agreement before entry into Review Manager 5. We included information about the number of participants treated and demographic details, type of cancer, drug and dosing regimen, study design (placebo or active control) and methods, study duration and follow-up, analgesic outcome measures and results, withdrawals, and adverse events. We collated multiple reports of the same study, so that each study, rather than each report, was the unit of interest in the review. We assessed the evidence using GRADE and created a 'Summary of findings' table.The main outcomes of interest for benefit were pain reduction of 30% or greater and 50% or greater from baseline, participants with pain no worse than mild, and participants feeling much improved or very much improved.

MAIN RESULTS

We included 10 studies (12 reports) with 958 adult participants. All the studies enrolled participants with chronic malignant tumour-related pain who were experiencing pain intensities described as moderate to severe, with most experiencing at least 4/10 with current treatment. The mean ages were 59 to 70 years, with participants aged between 24 and 87 years. Study length ranged from one day to six months. Five studies used a cross-over design. Tramadol doses ranged from 50 mg as single dose to 600 mg per day; doses of 300 mg per day to 400 mg per day were most common.Nine studies were at high risk of bias for one to four criteria (only one high risk of bias for size). We judged all the results to be very low quality evidence because of widespread lack of blinding of outcome assessment, inadequately described sequence generation, allocation concealment, and small numbers of participants and events. Important outcomes were poorly reported. There were eight different active comparators and one comparison with placebo. There was little information available for any comparison and no firm conclusions could be drawn for any outcome.Single comparisons of oral tramadol with codeine plus paracetamol, of dihydrocodeine, and of rectal versus oral tramadol provided no data for key outcomes. One study used tramadol combined with paracetamol; four participants received this intervention. One study compared tramadol with flupirtine - a drug that is no longer available. One study compared tramadol with placebo and a combination of cobrotoxin, tramadol, and ibuprofen, but the dosing schedule poorly explained.Two studies (191 participants) compared tramadol with buprenorphine. One study (131 participants) reported a similar proportion of no or mild pain at 14 days.Three studies (300 participants) compared tramadol with morphine. Only one study, combining tramadol, tramadol plus paracetamol, and paracetamol plus codeine as a single weak-opioid group reported results. Weak opioid produced reduction in pain of at least 30% from baseline in 55/117 (47%) participants, compared with 91/110 (82%) participants with morphine. Weak opioid produced reduction in pain of at least 50% in 49/117 (42%) participants, compared with 83/110 (75%) participants with morphine.There was no useful information for any other outcome of benefit or harm.

AUTHORS' CONCLUSIONS

There is limited, very low quality, evidence from randomised controlled trials that tramadol produced pain relief in some adults with pain due to cancer and no evidence at all for children. There is very low quality evidence that it is not as effective as morphine. This review does not provide a reliable indication of the likely effect. The likelihood that the effect will be substantially different is very high. The place of tramadol in managing cancer pain and its role as step 2 of the WHO analgesic ladder is unclear.

Abhängigkeitspotenzial und andere Risiken von Opioidanalgetika im Alter

Zusammenfassung. Zielsetzung: Übersicht über Suchtpotenzial und andere Risiken von Opioidanalgetika im höheren Lebensalter. Methodik: Narrativ review. Literaturrecherche in PubMed (Suchbegriffe: opioid analgesics UND abuse; opioid analgesics UND dependence; opioid analgesics UND addiction; opioid analgesics UND adverse effects; jeweils UND elderly) sowie aktuellen einschlägigen Standardwerken; Auswahl nach altersmedizinischer Relevanz und Aktualität. Ergebnisse: Die Verordnung von Opioidanalgetika (OA) hat in den letzten 25 Jahren massiv zugenommen, die weitaus meisten Verordnungen entfallen auf alte Menschen und Menschen mit chronischen Nicht-Tumorschmerzen (CNTS). Die diagnostischen Kriterien für die Opiatabhängigkeit in ICD-10 und DSM-5 sind für die OA-Behandlung von CNTS ungeeignet. Bei langfristiger OA-Behandlung bei CNTS kann eine spezifische Form von Abhängigkeit entstehen, die nicht mit der illegalen Opiat-(Heroin-)Sucht gleichzusetzen ist. Vorbestehende Suchterkrankungen und andere psychische Störungen sind die wesentlichsten Risikofaktoren. Weitere Nebenwirkungen sind zu beachten. Schmerztherapie bei Suchtkranken stellt eine besondere Herausforderung dar. Schlussfolgerungen: Die Anwendung von OA bei CNTS verlangt eine sorgfältige Indikationsstellung. Die besondere Form der Abhängigkeit von OA ist nicht ausreichend erforscht und wird zu wenig beachtet.

[Pain medication in nursing home residents with and without cancer. Most frequently with metamizole]

BACKGROUND

Pain is a highly prevalent symptom in nursing home residents. The analgesic pharmacotherapy of older adults is associated with challenges; however, studies from Germany examining the prescription pattern of analgesics in nursing home residents are rare.

OBJECTIVES

This study was carried out to examine the prescription of analgesics in nursing home residents with and without the diagnosis of cancer.

MATERIAL AND METHODS

Using health insurance claims data persons aged ≥ 65 years who were newly admitted to a nursing home between 2004 and 2009 and who survived at least the first 90 days after admission were included in the study. Cancer was identified by outpatient diagnoses of malignant neoplasms (ICD-10: C00-C97). Prescription drugs within the first 90 days after admission to a nursing home were analyzed which means that aspirin and acetaminophen were not taken into account.

RESULTS

A total of 5549 nursing home residents were included, who were on average 81.5 years old (56.8 % females). More than half (53.5 %) were assigned to care level I and 781 (14.1 %) were diagnosed with cancer. The study cohort received on average 7.8 different medications (with vs. without cancer: 8.6 vs. 7.6, respectively) and 43.8 % had prescriptions for analgesics (with vs. without cancer: 52.5 vs. 42.3 %, respectively). A total of 37.1 % were taking WHO step 1 analgesics (step 2: 11.4 % and step 3: 9.2 %). The proportion of persons receiving metamizole (dipyrone) was 28.3 % (with vs. without cancer: 35.6 vs. 27.1 %, respectively). Regarding all prescriptions, metamizole was by far the most frequently prescribed medication in nursing homes followed by melperone and omeprazole.

CONCLUSION

Approximately one third of nursing home residents received metamizole and most were long-term prescriptions. Considering that metamizole is associated with potentially life-threatening adverse effects, caution is indicated particularly when prescribed over long periods.

[Long-term opioid therapy in chronic noncancer pain. A systematic review and meta-analysis of efficacy, tolerability and safety in open-label extension trials with study duration of at least 26 weeks]

BACKGROUND

The efficacy and safety of long-term (≥ 6 months) opioid therapy (LtOT) in chronic noncancer pain (CNCP) is under debate. A systematic review with meta-analysis of the efficacy and harms of opioids in open-label extension studies of randomized controlled trials (RCTs) has not been conducted until now.

METHODS

We screened MEDLINE and clinicaltrials.gov (through to December 2013), as well as reference sections of systematic reviews of long-term RCTs of opioids in CNCP. We included open-label extension trials with a study duration ≥ 26 weeks of RCTs of ≥ 2 weeks duration. Using a random effects model, pooled estimates of event rates for categorical data and standardized mean differences (SMD) for continuous variables were calculated.

RESULTS

We included 11 open-label extension studies with 2445 participants with nociceptive (low back, osteoarthritis) and neuropathic (radicular, polyneuropathy) pain. Median study duration was 26 (range 26-108) weeks. Four studies tested oxycodone, two studies tramadol and buprenorphine; hydromorphone, morphine, oxymorphone and tapentadol were each tested in one study. Of the patients randomized at baseline, 28.5 % (95 % confidence interval, CI, 17.9-39.2 %) finished the open-label period; 53.5 % (95 % CI 38.1-68.2 %) of patients entering the open-label period finished the open-label period. In sum, the total loss was 71.5 % (95 % CI 60.9-83.1 %) of all patients primarily included into the RCT. A total of 4.9 % (95 % CI 2.9-8.2 %) of patients dropped out due lack of efficacy; 16.8 % (95 % CI 11.0-24.8 %) dropped out to due adverse events (AE) in the open-label period and 0.08 % (95 % CI 0.001-0.05 %) of patients died during the open-label period. Only one study systematically assessed aberrant drug behavior of the patients: 5.7 % (95 % CI 3.4-9.6 %) showed aberrant drug behavior in the opinion of the investigators and 2.6 % (95 % CI 1.2-5.8 %) were judged to show aberrant drug behavior by independent expert assessment. There was no significant change (p = 0.50) in pain intensity between the end of the randomized period and the end of open-label phase (SMD 0.19 [- 0.03, 0.41]; six studies with 1360 participants).

CONCLUSION

Only a minority of patients selected for opioid therapy at randomization finished the long-term open-label study. However, sustained effects of pain reduction could be demonstrated in these patients. LtOT can be considered in carefully selected and monitored CNCP patients who experience clinically meaningful pain reduction with at least tolerable AE in short-term opioid therapy. The English full-text version of this article is freely available at SpringerLink (under "Supplementary Material").

Dependence on Prescription Opioids

BACKGROUND

The incidence of initial prescriptions of opioids for chronic non-cancer pain rose by 37% in Germany from 2000 to 2010. Prescribing practice does not always conform with the recommendations of current guidelines. In the USA, 8-12% of patients with chronic non-cancer pain are opioid-dependent.

METHODS

This review is based on publications retrieved by a selective PubMed search and on the German S3 guideline on the long-term use of opioids in non-cancer pain.

RESULTS

Patients must be informed and counseled about the effects and risks of opioids before these drugs are prescribed. All opioid prescriptions for patients with chronic non-cancer pain should be regularly reviewed. The risk of abuse is high in young adults (odds ratio [OR] = 6.74) and in those with a history of substance abuse (OR = 2.34). Any unusual medication-related behavior, e.g., loss of prescriptions or increasing the dose without prior discussion with the physician, calls for further assessment by the physician in conversation with the patient. Urine testing for drugs and their metabolites is helpful as well. The goal of treatment of opioid abuse is opioid abstinence by gradual reduction of the dose. If this is not possible on an outpatient basis, hospitalization for drug withdrawal or substitution-based addiction therapy can be offered.

CONCLUSION

Physicians who know the indications and risks of opioid therapy and the typical behavior of drug-dependent patients will be better able to identify patients at risk and to prevent dependence. Studies on the prevalence of opioid abuse and dependence in German patients with chronic pain can help provide better estimates of the current extent and implications of this problem in Germany.