Codeine Shopping Behavior in a Retrospective Cohort of Chronic Noncancer Pain Patients: Incidence and Risk Factors

Trends in adverse drug reactions related to oral weak opioid analgesics in therapeutic use in adults: A 10-year French vigilances retrospective study

AIM

To describe the symptoms, patient demographics, and trends over time of adverse drug reactions (ADRs) related to weak opioid analgesics reported to the French vigilance networks.

METHODS

Retrospective study of data from French Poison Control Centers and Pharmacovigilance Centers databases of weak opioid analgesics-related ADRs cases, with high causality score, in adults, in therapeutic analgesic use, without co-exposure, between 2011 and 2020.

RESULTS

The number of cases was 388 in the Poisonings database and 155 in the Pharmacovigilance database; ratio of the number of these cases to all reported cases during the study period was 0.02% and 0.03%, respectively. Tramadol was most often involved (74% and 56.1%, respectively), followed by codeine (26% and 38.7%, respectively). There was no significant variation in the number of cases reported. Cases most often involved young adults (median age: 40 years) and mostly women (76%). Gastrointestinal symptoms were mostly reported (80% and 65%, respectively) as described in the Summary of Products Characteristics. Patterns of ADRs were comparable in both databases, except for codeine-associated acute pancreatitis and anaphylaxis that were reported in the Pharmacovigilance database. No fatality was observed. Severity was more often observed in the Pharmacovigilance database (30%) than in the Poisonings database (moderate toxicity: 7%).

CONCLUSION

ADRs mostly occurred among young women using tramadol, without significant variation in the number of reported cases over time. Serious ADRs were more frequently reported to the Pharmacovigilance database, particularly for codeine. Women seemed to be at greater risk of ADRs.

Problematic opioid use among osteoarthritis patients with chronic post-operative pain after joint replacement: analyses from the BISCUITS study

OBJECTIVES

Opioids are commonly used to manage pain, despite an increased risk of adverse events and complications when used against recommendations. This register study uses data of osteoarthritis (OA) patients with joint replacement surgery to identify and characterize problematic opioid use (POU) prescription patterns.

METHODS

The study population included adult patients diagnosed with OA in specialty care undergoing joint replacement surgery in Denmark, Finland, Norway, and Sweden during 1 January 2011 to 31 December 2014. Those with cancer or OA within three years before the first eligible OA diagnosis were excluded. Patients were allocated into six POU cohorts based on dose escalation, frequency, and dosing of prescription opioids post-surgery (definitions were based on guidelines, previous literature, and clinical experience), and matched on age and sex to patients with opioid use, but not in any of the six cohorts. Data on demographics, non-OA pain diagnoses, cardiovascular diseases, psychiatric disorders, and clinical characteristics were used to study patient characteristics and predictors of POU.

RESULTS

13.7% of patients with OA and a hip/knee joint replacement were classified as problematic users and they had more comorbidities and higher pre-surgery doses of opioids than matches. Patients dispensing high doses of opioids pre-surgery dispensed increased doses post-surgery, a pattern not seen among patients prescribed lower doses pre-surgery. Being dispensed 1-4,500 oral morphine equivalents in the year pre-surgery or having a non-OA pain diagnosis was associated with post-surgery POU (OR: 1.44-1.50, and 1.11-1.20, respectively).

CONCLUSIONS

Based on the discovered POU predictors, the study suggests that prescribers should carefully assess pain management strategies for patients with a history of comorbidities and pre-operative, long-term opioid use. Healthcare units should adopt risk assessment tools and ensure that these patients are followed up closely. The data also demonstrate potential areas for further exploration in improving patient outcomes and trajectories.

Transcultural validation of a French-European version of the Prescription Opioid Misuse Index Scale (POMI-5F)

PURPOSE

The Prescription Opioid Misuse Index scale (POMI) is a brief questionnaire used to assess opioid prescription misuse. In view of the increase in the prescription of opioid analgesics for chronic noncancer pain (CNCP), this tool is particularly useful during medical consultations to screen opioid misuse in patients using opioids. We sought to generate and validate a French-European translation of the POMI.

METHODS

We conducted an observational, longitudinal, and multicenter psychometric study with crosscultural validation. All adult CNCP patients who were treated with opioids for at least three months, were followed in pain clinics, and spoke French were eligible. From September 2015 to November 2017, we included 163 patients and analyzed 154. We performed a pretest on a sample of representative patients to evaluate acceptability and understanding of translation. Study patients completed the POMI scale at a pain clinic (test phase), and we assessed test-retest reliability after two to four weeks by a second completion of the POMI scale at home by patients (retest phase). We subsequently explored psychometric properties of the POMI (acceptability, internal consistency, reproducibility, and external validity).

RESULTS

Due to poor internal consistency and reproducibility, items 4, 7, and 8 of the original POMI scale were removed, and we proposed a five-question French-European version (POMI-5F). The internal consistency of POMI-5F was good (Cronbach's α = 0.71), as was test-retest reliability (r = 0.65 [0.55-0.67]). The external validity of POMI-5F, compared with the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, was moderate but significant (r = 0.45; P < 0.001). The optimal POMI-5F cut-off score to indicate misuse was 2/5 (sensitivity = 0.95 and specificity = 0.54).

CONCLUSION

We generated and validated a French-European translation of the POMI scale, POMI-5F, for use by French researchers and physicians to identify opioid misuse in CNCP patients.

Oral Morphine as an Alternative Substitution Treatment for Opioid Use Disorder, a Rare but Non-risk-free Use

Background

National health monitoring agencies have reported the alternative use of morphine sulfate painkiller for maintenance treatment of opioid use disorder (OUD), associated with a potential increase in overdose risk.

Objectives

This study sought to assess the prevalence of regular and occasional legally prescribed morphine use in patients treated for OUD and compare their characteristics to those of patients receiving conventional opioid maintenance treatment (OMT), buprenorphine or methadone. Then, we assessed the factors associated with opioid overdose risk.

Methods

Data were extracted from the French national healthcare system database, covering the entire population in 2015. Diagnosis associated with hospital discharge and long-term disease codes were extracted to select the population and identify outcomes and covariates. OUD non-chronic pain patients were divided into regular (≤35 days between dispensing and ≥3 months of continuous treatment duration) morphine users, and occasional users. Their sociodemographic and health characteristics were compared to OMT controls. A multivariate logistic regression model was performed to determine factors associated with opioid overdose.

Results

In patients treated for OUD, 2,237 (2.2%) morphine users (1,288 regular and 949 occasional), 64,578 (63.7%) buprenorphine and 34,638 (34.1%) methadone controls were included. The prevalence of regular morphine use among patients treated for OUD regularly receiving an opioid was 1.3%. Compared to users who receive morphine regularly, occasional users had an increased risk of overdose [OR = 2.2 (1.5-3.3)], while the risk was reduced in the buprenorphine group [OR = 0.5 (0.4-0.7)] and not significantly different for methadone [OR = 1.0 (0.7-1.4)]. Other overdose risk factors were low-income, comorbidity, i.e., psychiatric conditions, alcohol use disorder or complications related to intravenous drug use, and coprescription with benzodiazepines or pregabalin. These factors were more frequent in morphine groups.

Conclusions

Patients that were prescribed oral morphine represented a small minority of the treated for OUD. The poorer health condition affected by numerous comorbidities and higher risk of opioid overdose in patients treated with oral morphine compared with OMT controls points toward the need to better supervise the practices of these patients, to strengthen multidisciplinary care and risk reduction measures.

Doctor shopping among chronic noncancer pain patients treated with opioids in the province of Quebec (Canada): incidence, risk factors, and association with the occurrence of opioid overdoses

Opioid doctor shopping was a rare phenomenon among people living with chronic noncancer pain but was associated with the occurrence of opioid overdoses.

Introduction:

Prescription opioids continue to be involved in the opioid crisis, and a better understanding of factors associated with problematic opioid use is needed.

Objectives:

The aim of this study was to assess the incidence of opioid doctor shopping, a proxy for problematic opioid use, to identify associated risk factors, and to assess its association with the occurrence of opioid overdoses.

Methods:

This was a retrospective cohort study of people living with chronic noncancer pain (CNCP) and treated with opioids for at least 6 months between 2006 and 2017 in the province of Quebec (Canada). Data were drawn from the Quebec health administrative databases. Doctor shopping was defined as overlapping prescriptions written by ≥ 2 prescribers and filled in ≥3 pharmacies.

Results:

A total of 8,398 persons with CNCP were included. The median age was 68.0 (Q1: 54; Q3: 82) years, and 37.1% were male. The 1-year incidence of opioid doctor shopping was 7.8%, 95% confidence interval (CI): 7.2–8.5. Doctor shopping was associated with younger age (hazard ratio [HR] 18–44 vs ≥65 years: 2.22, 95% CI: 1.77–2.79; HR 45–64 vs ≥65 years: 1.34, 95% CI: 1.11–1.63), male sex (HR = 1.20, 95% CI: 1.01–1.43), history of substance use disorder (HR = 1.32, 95% CI: 1.01–1.72), and anxiety (HR = 1.41, 95% CI: 1.13–1.77). People who exhibited doctor shopping were 5 times more likely to experience opioid overdoses (HR = 5.25, 95% CI: 1.44–19.13).

Conclusion:

Opioid doctor shopping is a marginal phenomenon among people with CNCP, but which is associated with the occurrence of opioid overdoses. Better monitoring of persons at high risk to develop doctor shopping could help prevent opioid overdoses.

Opioid Doctor Shopping: A Rare Phenomenon Among Patients with Chronic Non-Cancer Pain Followed in Tertiary Care Settings

Background

Opioid doctor shopping has not yet been investigated in patients followed in tertiary care settings. This study aimed at assessing the prevalence of opioid doctor shopping among patients with chronic non-cancer pain (CNCP) (ie, pain lasting ≥3 months) attending multidisciplinary pain clinics in Quebec, Canada.

Patients and Methods

This was a retrospective cohort study of patients with CNCP enrolled in the Quebec Pain Registry (QPR) between 2008 and 2014. QPR data were linked to the Quebec health insurance databases. The index date was the date of the first visit at the pain clinic. Prevalence of doctor shopping was assessed within the 12 months following the index date. Doctor shopping was defined as at least 1 day of overlapping opioid prescriptions from ≥2 prescribers and filled in ≥3 pharmacies.

Results

A total of 2191 patients with CNCP with at least one opioid dispensation within the 12 months following the index date were included. The mean age was 58.6±14.9 years and 41.3% were men. The median pain duration was 4 years, and 13.3% of patients were diagnosed with neuropathic pain. Regarding past year comorbidities, 15.0% presented anxiety, 16.8% depression and 6.4% substance use disorder. Among the included patients, 15 (0.7%) presented at least one episode of doctor shopping. Among these doctor-shoppers, 9 (60.0%) exhibited only 1 episode.

Conclusion

Opioid doctor shopping is a rare phenomenon among patients with CNCP treated in tertiary care settings. Opioids should remain a drug option for patients without substance use disorder, and who have persistent pain despite optimized nonopioid therapy.

Analgesic opioid use disorders in patients with chronic non-cancer pain: A holistic approach for tailored management

Chronic pain is a major public health issue that frequently leads to analgesic opioid prescriptions. These prescriptions could cause addiction issues in high-risk patients with associated comorbidities, especially those of a psychiatric, addictive, and social nature. Pain management in dependent patients is complex and is yet to be established. By combining the views of professionals from various specialties, we conducted an integrative review on this scope. This methodology synthesizes knowledge and results of significant practical studies to provide a narrative overview of the literature. The main results consisted in first proposing definitions that could allow shared vocabulary among health professionals regardless of their specialties. Next, a discussion was conducted around the main strategies for managing prescription opioid dependence, as well as pain in the context of opioid dependence and associated comorbidities. As a conclusion, we proposed to define the contours of holistic management by outlining the main guidelines for creating a multidisciplinary care framework for multi-comorbid patients with chronic pathologies.

Risk assessment of using off-label morphine sulfate in a population-based retrospective cohort of opioid-dependent patients

AIMS

Several addictovigilance studies have described the off-label use of morphine sulfate (MS) for nonchronic pain in opioid use disorder (OUD) patients as an alternative to conventional opioid substitution treatments (OSTs). This study primarily sought to compare the incidence of unintentional opioid-related overdose in the year following the prescription initiation in off-label MS users, compared to OST-maintained patients.

METHODS

Sequential cohorts of OUD patients who were regularly dispensed MS, buprenorphine, or methadone, between 1 April 2012 and 31 December 2014, were retrospectively identified using the French nationwide healthcare data system. The incidence of overdoses, deaths, doctor shopping, and complications of a viral, bacterial or thrombotic nature, was compared using the Cox regression method.

RESULTS

Overall, 1075, 20 834 and 9778 OUD patients without chronic-pain were included in the MS, buprenorphine, and methadone cohorts, respectively. Overdose incidence was 3.8 (P < .01 [95% confidence interval (CI): 2.1-6.8]) and 2.0 (P = .02 [95%CI: 1.1-3.6]) higher in the MS cohort vs buprenorphine and methadone, respectively. Death incidence was 9.1 (P < .01 [95%CI: 3.2-25.9]) and 3.9 (P < .01 [95%CI: 1.4-10.7]) higher in the MS cohort vs buprenorphine and methadone, respectively. The incidences of other associated risks were significantly higher in the MS group vs OSTs, except for hepatitis C viral infection and thrombotic complications.

CONCLUSION

This first French comprehensive nationwide study reveals increasing overdose, death, bacterial infection, abuse and diversion risks when off-label MS is initiated as alternative to OST. These results question the relevance of prescribing MS as a safe opioid maintenance treatment, considering its health risk profile.

Identification of factors influencing tampering of codeine-containing medicines in England: a qualitative study

Background

Tampering of psychoactive medicines presents challenges to regulation and public health. However, little is currently known about what influences the decisions to treat codeine-containing medicines (CCM) with cold water extraction (CWE) from the perspective of individuals employing these techniques. The article identifies factors influencing utilisation of CWE to separate codeine from compounded analgesics, such as paracetamol and ibuprofen, found in CCM.

Methods

Purposive sampling of 27 participants residing in England who took part in a qualitative interview. Of these, 14 individuals (11 males and 3 females) reported tampering of psychoactive medicines, and the relevant transcripts were included in the analyses for the study. Participants were recruited from one addiction treatment service and from an online survey. The mean age of the participants was 31.5 years (range = 18–42 years). Qualitative data analysis followed the processes of iterative categorization (IC). The codes ‘harm reduction’, ‘information sources’ and ‘changes on the drug markets’ were grouped and summarised. The coding of the data was done in a Microsoft® Word document.

Results

Two groups of participants were identified in the data analysis: (i) individuals who used CCM (n = 5), and (ii) individuals who used CCM and heroin (n = 9). Participants in both groups used CWE due to concerns of paracetamol overdose from the use of excessive dosages of CCM. For both of them, information obtained from the internet encouraged the use of CWE. Participants using CCM described how the many steps involved in conducting CWE, including sourcing codeine boxes from pharmacies (over the counter), presented a barrier against using CWE. Participants using CCM and heroin explained how reduced availability in the local heroin supply influenced utilisation of CWE techniques to maintain their use of opioids and avoid withdrawal. Withdrawal symptoms and cravings outweighed the concerns about the quality of the extracted codeine mixtures in this participant group, especially the ability of CWE to remove paracetamol and tablet fillers.

Conclusions

Utilisation of CWE of codeine was influenced by several factors including drug market supply, the availability of detailed information on the internet about CWE and restrictions on codeine sourcing in pharmacies. Risks identified with CWE include consumption of unknown doses of paracetamol if the CWE techniques are not used correctly. Attempts at extracting codeine from CCM should be considered in risk assessments of opioid medicines.

Multiple opioid prescribers: A genuine quest for treatment rather than aberrant behaviour. A two-decade population-based study

BACKGROUND

Accessing multiple prescribers for opioid prescription, referred to as doctor-shopping, is associated with an increased risk of opioid overdose and fatalities.

AIM

The primary aim of this study was to assess the probability of accessing multiple prescribers among patients dispensed prescription opioids.

METHOD

A retrospective population-based study using the Monitoring of Drugs of Dependence system of the Medicines Monitoring Unit (MMU) of Queensland Health, Australia. We assessed the odds of accessing multiple prescribers across both -short-term (≤1 month, 2-3 months) and longer-term (4-6 months and ≥7 months). We examined the relationship between multiple doctor visits, the dispensed dose of opioid and patient's residential socioeconomic status (SES).

RESULT

Compared to those dispensed opioid prescriptions for ≥7-12 months, those dispensed opioids for ≤1 month were more likely to have visited ≥3 prescribers (adjusted odds ratio (aOR)) 4.06, 95% CI 4.01, 4.10, while for 2-3 months and 4-6 months the odds were aOR 2.36, 95% CI 2.33, 2.39 and aOR 1.79, 95% CI 1.74, 1.79 respectively. Patients dispensed opioid doses of ≥100 oral morphine milligram equivalent per day (MME/day) were more likely to obtain prescriptions from ≥3 prescribers compare to those receiving a dose of <20MME/day (aOR 1.90; 95% CI 1.87, 1.94). The probability of obtaining opioid prescriptions from multiple prescribers increased as the socioeconomic status decreased: aOR 1.41; 95% CI 1.38, 1.44 for lowest SES compared to the highest SES.

CONCLUSION

Patients were more than four time likely to be dispensed opioid prescriptions from multiple prescribers within the first 30 days of initiating opioid treatment, possibly as part of multidisciplinary referral post-hospital discharge. High dose opioid and low SES was associated with higher probability of accessing multiple prescribers.

Replacement of current opioid drugs focusing on MOR-related strategies

The scarcity and limited risk/benefit ratio of painkillers available on the market, in addition to the opioid crisis, warrant reflection on new innovation strategies. The pharmacopoeia of analgesics is based on products that are often old and derived from clinical empiricism, with limited efficacy or spectrum of action, or resulting in an unsatisfactory tolerability profile. Although they are reference analgesics for nociceptive pain, opioids are subject to the same criticism. The use of opium as an analgesic is historical. Morphine was synthesized at the beginning of the 19th century. The efficacy of opioids is limited in certain painful contexts and these drugs can induce potentially serious and fatal adverse effects. The current North American opioid crisis, with an ever-rising number of deaths by opioid overdose, is a tragic illustration of this. It is therefore legitimate to develop research into molecules likely to maintain or increase opioid efficacy while improving their tolerability. Several avenues are being explored including targeting of the mu opioid receptor (MOR) splice variants, developing biased agonists or targeting of other receptors such as heteromers with MOR. Ion channels acting as MOR effectors, are also targeted in order to offer compounds without MOR-dependent adverse effects. Another route is to develop opioid analgesics with peripheral action or limited central nervous system (CNS) access. Finally, endogenous opioids used as drugs or compounds that modify the metabolism of endogenous opioids (Dual ENKephalinase Inhibitors) are being developed. The aim of the present review is to present these various targets/strategies with reference to current indications for opioids, concerns about their widespread use, particularly in chronic non-cancer pains, and ways of limiting the risk of opioid abuse and misuse.

Characteristics of doctor-shoppers: a systematic literature review

Objective: Doctor-shopping has significant consequences for patients and payers and can indicate misuse of drugs, polypharmacy, less continuity of care, and increased medical expenses. This study reviewed the literature describing doctor-shoppers in the adult population. Methods: A systematic literature review was performed in PubMed and supplemented by a Google search of grey literature. Overall, 2885 records were identified; 43 papers served as a source of definition of a doctor-shopper, disease, treatment, patient characteristics, patient special needs, country. Results: Definitions of doctor-shopping were heterogeneous. Overall, 40% of studies examined the use of opioids, antidepressants, or psychoactive drugs, while the others focused on chronic or frequent diseases. Most studies were conducted in countries with easy access to healthcare resources (USA, France, Taiwan, Hong Kong). The prevalence of doctor-shopping ranged from 0.5% among opioid users in the USA to 25% of patients registered at general practices in Japan. Comorbidities, active substance abuse, greater distance from healthcare facility, younger age, longer disease and poor patient satisfaction increased doctor-shopping. Conclusions: Knowing the characteristics of doctor-shoppers may help identify such patients and reduce the associated waste of medical resources, but concerns about the misuse of drugs or healthcare resources should not prevent proper disease management.

Prescription opioid analgesic use in France: Trends and impact on morbidity-mortality

BACKGROUND

While data from USA and Canada demonstrate an opioid overdose epidemic, very little nation-wide European studies have been published on this topical subject.

METHODS

Using a nationally representative sample of the French Claims database (>700,000 patients), the exhaustive nationwide hospital discharge database, and national mortality registry, all patients dispensed at least one prescription opioid (PO) in 2004-2017 were identified, to describe trends in PO analgesic use, shopping behaviour, opioid-related hospitalizations and deaths. Annual prevalence of PO use and shopping behaviour (≥1 day of overlapping prescriptions from ≥2 prescribers, dispensed by ≥3 pharmacies) was estimated.

RESULTS

In 2004-2017, the annual prevalence of weak opioid use codeine, tramadol and opium rose by 150%, 123%, and 244%, respectively (p < 0.05). Strong opioid use increased from 0.54% to 1.1% (+104%, p < 0.05), significantly for oxycodone (+1950%). Strong opioid use in chronic noncancer pain rose by 88% (p < 0.05) and 1180% for oxycodone. Opioid shopping increased from 0.50% to 0.67% (+34%, p < 0.05), associated with higher mortality risk HR = 2.8 [95% confidence interval (CI): 1.2-6.4]. Opioid-related hospitalizations increased from 15 to 40 per 1,000,000 population (+167%, 2000-2017), and opioid-related deaths from 1.3 to 3.2 per 1,000,000 population (+146%, 2000-2015).

CONCLUSIONS

This study provided a first European approach to a nationwide estimation with complete access to several national registries. In 2004-2017 in France, PO use excluding dextropropoxyphene more than doubled. The increase in oxycodone and fentanyl use, and nontrivial increasing trend in opioid-related morbidity-mortality should prompt authorities to closely monitor PO consumption in order to prevent alarming increases in opioid-related morbidity-mortality.

SIGNIFICANCE

In 2004-2017, prescription opioid use in France at least doubled and oxycodone use increased particularly, associated with a nontrivial increase in opioid-related morbidity-mortality. Although giving no indication for an 'opioid epidemic,' these findings call for proper monitoring of opioid use.

The source and diversion of pharmaceutical drugs for non-medical use: A systematic review and meta-analysis

BACKGROUND

The non-medical use (NMU) of pharmaceutical drugs is an increasing public health concern. This systematic review consolidates current knowledge about how pharmaceutical drugs are obtained for NMU and the processes and people involved in diversion.

METHODS

Peer-reviewed and grey literature databases were searched for empirical studies published between 1996 and 2017 that examined the source or diversion of pharmaceutical opioids, sedatives or stimulants for NMU in countries with reported misuse problems. Pooled prevalence meta-analyses using random effects models were used to estimate the prevalence of medical and non-medical sourcing reported by end-users, and gifting, selling and trading by various populations.

RESULTS

This review synthesizes the findings of 54 cross-sectional studies via meta-analyses, with a remaining 95 studies examined through narrative review. Pharmaceutical drugs are primarily sourced for NMU from friends and family (57%, 95% CI 53%-62%, I² = 98.5, n = 30) and despite perceptions of healthcare professionals to the contrary, illegitimate practices such as doctor shopping are uncommon (7%, 95% CI 6%-10%, I² = 97.4, n = 29). Those at risk of diversion include patients displaying aberrant medication behaviors, people with substance use issues and students in fraternity/sorority environments. Sourcing via dealers is also common (32%, 95% CI 23%-41%, I² = 99.8, n = 25) and particularly so among people who use illicit drugs (47%, 95% CI 35%-60%, I² = 99.1, n = 15). There is little to no organized criminal involvement in the pharmaceutical black market.

CONCLUSION

Pharmaceutical drugs for NMU are primarily sourced by end-users through social networks. Future research should examine how dealers source pharmaceutical drugs.