Risk of death during and after opiate substitution treatment in primary care: prospective observational study in UK General Practice Research Database

A Novel Use of the "3-Day Rule": Post-discharge Methadone Dosing in the Emergency Department

Introduction

Methadone is a medically necessary and lifesaving medication for many patients with opioid use disorder. To adequately address these patients' needs, methadone should be offered in the hospital, but barriers exist that limit its continuation upon discharge. The code of federal regulations allows for methadone dosing as an inpatient as well as outpatient dispensing for up to three days to facilitate linkage to treatment. As a quality initiative, we created a new workflow for discharging patients on methadone to return to the emergency department (ED) for uninterrupted dosing.

Methods

Our addiction medicine team changed hospital methadone policy to better allow hospitalization as a window of opportunity to start methadone. This necessitated the creation of a warm-handoff process to link patients to methadone clinics if that linkage could not happen immediately on discharge. Thus, our team created the "ED Bridge" process, which uses the "3-day rule" to dispense methadone from the ED post hospital discharge. We then followed every patient we directed through this workflow as an observational cohort for outcomes and trends.

Results

Of the patients for whom ED bridge dosing was planned, 40.4% completed all bridge dosing and an additional 17.3% received at least one but not all bridge doses. Established methadone patients made up 38.1% of successful linkages, and 61.9% were patients who were newly started on methadone in the hospital.

Conclusion

Improving methadone as a treatment option remains an ongoing issue for policymakers and advocates. Our ED bridge workflow allows us to expand access and continuation of methadone now using existing laws and regulations, and to better use hospitals as a point of entry into methadone treatment.

Multiple Episodes of Cardiac Arrest Induced by Treatment With Ibogaine: A Case Report

Opioid dependence is a common problem, and therapeutic alternatives are scarce and ineffective. Ibogaine, illegal in several countries, has been reported as a possible therapy in alternative clinics and it is also used as a recreational drug, despite its cardiotoxic potential, including QT prolongation. We report a case of long QT leading to multiple episodes of cardiac arrest after a single dose of ibogaine (200mg, 2.6mg/Kg) in a patient without structural heart disease. This case highlights the fact that even low doses of ibogaine can be lethal and warns us about the consequences of its use.

Buprenorphine Receipt and Retention for Opioid Use Disorder Following an Initiative to Increase Access in Primary Care

OBJECTIVES

Buprenorphine, a medication for opioid use disorder (OUD), is underutilized in general medical settings. Further, it is inequitably received by racialized groups and persons with comorbidities. The Veterans Health Administration launched an initiative to increase buprenorphine receipt in primary care. The project's objective was to identify patient-related factors associated with buprenorphine receipt and retention in primary care clinics (n = 18) participating in the initiative.

METHODS

Retrospective cohort quality improvement evaluation of patients 18 years or older with 2 or more primary care visits in a 1-year period and an OUD diagnosis in the year before the first primary care visit (index date). Buprenorphine receipt was the proportion of patients with OUD who received 1 or more buprenorphine prescriptions from primary care providers during the post-index year and retention the proportion who received buprenorphine for 180 days or longer.

RESULTS

Of 2880 patients with OUD seen in primary care, 11.7% (95% confidence interval [CI], 10.6%-12.9%) received buprenorphine in primary care, 58.2% (95% CI, 52.8%-63.3%) of whom were retained on buprenorphine for 180 days or longer. Patients with alcohol use disorder (adjusted odds ratio [AOR], 0.39; 95% CI, 0.27-0.57), nonopioid drug use disorder (AOR, 0.64; 95% CI, 0.45-0.93), and serious mental illness (AOR, 0.60; 95% CI, 0.37-0.97) had lower buprenorphine receipt. Those with an anxiety disorder had higher buprenorphine receipt (AOR, 1.42; 95% CI, 1.04-1.95). Buprenorphine receipt (AOR, 0.55; 95% CI, 0.35-0.87) and 180-day retention (AOR, 0.40; 95% CI, 0.19-0.84) were less likely among non-Hispanic Black patients.

CONCLUSIONS

Further integration of addiction services in primary care may be needed to enhance buprenorphine receipt for patients with comorbid substance use disorders, and interventions are needed to address disparities in receipt and retention among non-Hispanic Black patients.

Health-care resource use among patients who use illicit opioids in England, 2010-20: A descriptive matched cohort study

BACKGROUND AND AIMS

People who use illicit opioids have higher mortality and morbidity than the general population. Limited quantitative research has investigated how this population engages with health-care, particularly regarding planned and primary care. We aimed to measure health-care use among patients with a history of illicit opioid use in England across five settings: general practice (GP), hospital outpatient care, emergency departments, emergency hospital admissions and elective hospital admissions.

DESIGN

This was a matched cohort study using Clinical Practice Research Datalink and Hospital Episode Statistics.

SETTING

Primary and secondary care practices in England took part in the study.

PARTICIPANTS

A total of 57 421 patients with a history of illicit opioid use were identified by GPs between 2010 and 2020, and 172 263 patients with no recorded history of illicit opioid use matched by age, sex and practice.

MEASUREMENTS

We estimated the rate (events per unit of time) of attendance and used quasi-Poisson regression (unadjusted and adjusted) to estimate rate ratios between groups. We also compared rates of planned and unplanned hospital admissions for diagnoses and calculated excess admissions and rate ratios between groups.

FINDINGS

A history of using illicit opioids was associated with higher rates of health-care use in all settings. Rate ratios for those with a history of using illicit opioids relative to those without were 2.38 [95% confidence interval (CI) = 2.36-2.41] for GP; 1.99 (95% CI = 1.94-2.03) for hospital outpatient visits; 2.80 (95% CI = 2.73-2.87) for emergency department visits; 4.98 (95% CI = 4.82-5.14) for emergency hospital admissions; and 1.76 (95% CI = 1.60-1.94) for elective hospital admissions. For emergency hospital admissions, diagnoses with the most excess admissions were drug-related and respiratory conditions, and those with the highest rate ratios were personality and behaviour (25.5, 95% CI = 23.5-27.6), drug-related (21.2, 95% CI = 20.1-21.6) and chronic obstructive pulmonary disease (19.4, 95% CI = 18.7-20.2).

CONCLUSIONS

Patients who use illicit opioids in England appear to access health services more often than people of the same age and sex who do not use illicit opioids among a wide range of health-care settings. The difference is especially large for emergency care, which probably reflects both episodic illness and decompensation of long-term conditions.

Patient's and healthcare provider's experiences with Opioid Maintenance Treatment (OMT): a qualitative evidence synthesis

BACKGROUND

Opioid Maintenance Treatment (OMT) is the gold standard for people with opioid dependence. However, drop-out rates are high, and many patients do not reach desired outcomes. Understanding patients' and healthcare providers' experiences with the treatment can provide valuable information to improve the quality of OMT and to increase acceptability and accessibility of services. The aim of this systematic review is to explore and synthesise the experiences of OMT among persons with opioid dependence and health care providers, to inform policy makers and practitioners on how to improve OMT outcomes.

METHODS

We conducted a qualitative evidence synthesis. We systematically searched in electronic databases (CINAHL, Embase, MEDLINE, and nordic databases) and searched for grey literature. As we identified many studies that met our inclusion criteria, we purposively sampled a manageable number of studies to include in this review. Two researchers independently extracted and coded data from the included studies and used the Andersen's healthcare utilization model to organize and develop codes. We assessed the methodological limitations of the studies, and our confidence in the findings using GRADE CERQual.

RESULTS

We retrieved 56 relevant studies and purposively sampled 24 qualitative studies of patients' and healthcare providers' experiences with OMT. Our analyses resulted in six main themes: (1) External stigma prevents engagement and retention in treatment, (2) Being identified as in OMT contributed to an increased experience of stigma (3) Inadequate knowledge and expertise among healthcare providers affected patients' treatment experiences, (4) Quality of communication between personnel and patients impacts patients' engagement with treatment and treatment outcomes, (5) Patients wanted help with many aspects of their lives not just medication, and (6) Balancing positive expectations of OMT with treatment stigma. We found that stigma was an overarching theme across these themes.

CONCLUSION

Our findings suggest that OMT could be more beneficial for patients if treatment programs prioritize efforts to diminish societal and OMT provider stigma and find strategies to better address patient needs. Initiatives should focus on improving treatment knowledge among providers, encouraging the use of client perspectives, considering the context of family members, and establishing a more holistic and flexible treatment environment.

The Therapeutic Potential of Cannabidiol in Revolutionising Opioid Use Disorder Management

Opioid use disorder (OUD) is a significant cause of morbidity and mortality worldwide and is linked to a complex interplay of biopsychosocial factors as well as the increasing overprescription and availability of opioid medications. Current OUD management relies on the controlled provision of opioid medications, such as methadone or buprenorphine, known as opioid replacement therapy. There is variable evidence regarding the long-term efficacy of these medications in improving the management of OUD, thereby necessitating an exploration into innovative approaches to complement, or even take the place of, existing treatment paradigms. Cannabidiol (CBD), a non-psychoactive compound derived from the cannabis plant, has garnered attention for its diverse pharmacological properties, including anti-inflammatory, analgesic, and anxiolytic effects. Preliminary studies suggest that CBD may target opioid withdrawal pathways that make CBD a potential therapeutic option for OUD. This narrative review synthesises current literature surrounding OUD and offers a nuanced review of the current and future role of CBD in managing this condition. In doing so, we highlight the potential avenues to explore with respect to CBD research for the guidance and development of further research opportunities, framework and policy development, and clinical considerations before medicinal CBD can be integrated into evidence-based clinical guidelines.

Non-fatal overdose risk associated with prescribing opioid agonists concurrently with other medication: Cohort study conducted using linked primary care, secondary care and mortality records

BACKGROUND AND AIMS

An apparently protective effect of opioid agonist treatment (OAT) on all-cause and cause-specific mortality risk has been widely reported. Non-fatal overdose (NFO) often precedes subsequent drug-poisoning deaths. We hypothesized that benzodiazepines, gabapentinoids, antipsychotics, antidepressants, Z-drugs or opioids increase the NFO risk when co-prescribed with OAT.

DESIGN

We conducted a cohort study using the Clinical Practice Research Datalink GOLD and Aurum databases. The cohort was linked to Hospital Episode Statistics admitted patient care data (HES-APC), neighbourhood- and practice-level Index of Multiple Deprivation quintiles and mortality records from the Office for National Statistics.

SETTING

Primary care in England.

PARTICIPANTS

We studied patients with opioid use disorder, aged 18-64 years, who were prescribed OAT (15155 methadone and 5743 buprenorphine recipients) between Jan 1, 1998, and Dec 31, 2017.

MEASUREMENTS

The main outcome examined was NFO risk during co-prescription of OAT with benzodiazepines, antipsychotics, gabapentinoids, antidepressants, Z-drugs or opioids. Overdose was defined according to International Classification of Diseases codes from the HES-APC data set. Negative binomial regression models were used to estimate weighted rate ratios (wRR) for NFO during co-prescription of OAT and benzodiazepines, antipsychotics, gabapentinoids, antidepressants, Z-drugs or opioids with periods of exclusive OAT usage.

FINDINGS

Among 20 898 patients observed over 83 856 person-years, we found an elevated overdose risk that resulted in hospital admission during co-prescription of OAT with benzodiazepines [wRR: 1.45; 95% confidence interval (CI) = 1.26-1.67], gabapentinoids (wRR = 2.22; 95% CI = 1.77-2.79), Z-drugs (wRR = 1.60; 95% CI = 1.31-1.96), antipsychotics (wRR = 1.85; 95% CI = 1.53-2.25) and opioids (wRR = 1.28; 95% CI = 1.02-1.60). The risk ratio for antidepressant co-prescriptions was below unity (wRR = 0.90; 95% CI = 0.79-1.02) but this result was not statistically significant.

CONCLUSION

Elevated risk of non-fatal overdose among opioid agonist treatment recipients is associated with concurrent use of medication prescribed for other reasons.

Increased risk of non-fatal overdose associated with non-prescribed benzodiazepine use in Scotland, UK

BACKGROUND

Drug-related deaths (DRDs) in Scotland increased for seven years in a row between 2014 and 2020, consolidating Scotland's place at the top of the United Kingdom and European drug-related mortality charts. One of the defining features of this recent and rapid rise has been the role of benzodiazepines, which are now involved in the majority of all DRDs. These deaths are linked to use of non-prescribed, benzodiazepine-type novel psychoactive substances (NPS) which have been identified by the United Nations as a global threat to public health. This study aimed to estimate the prevalence and determinants of non-prescribed benzodiazepine use and its association with recent non-fatal overdose among a national sample of people who inject drugs (PWID).

METHODS

Data from the 2019-20 Needle Exchange Surveillance Initiative (NESI) was analysed using logistic regression. NESI is a voluntary, anonymous, biennial, cross-sectional, bio-behavioural survey of PWID attending community-based services providing injecting equipment in mainland Scotland.

RESULTS

Prevalence of non-prescribed benzodiazepine use in the past six months was 52% and significantly associated with age (aOR 0.97, 0.96-0.98), frequent incarceration (aOR 1.29, 1.07-1.57), recent public injecting (aOR 3.25, 2.33-4.55), a recent methadone prescription (aOR 1.87, 1.51-2.33), and a history of benzodiazepine prescription (aOR 1.92, 1.47-2.52). In addition, non-prescribed benzodiazepine use was significantly associated with non-fatal overdose in the past year among PWID (aOR 2.47, 1.90-3.21).

CONCLUSION

This study found a high prevalence of non-prescribed benzodiazepine use among a national sample of PWID in Scotland. Prevalence was highest among populations known to be at increased risk of drug-related death and use was strongly associated with overdose. These novel findings highlight the scale of the non-prescribed benzodiazepine issue Scotland faces, and the urgency required to expand its harm reduction infrastructure to address this unique element of its overdose crisis.

UK research data resources based on primary care electronic health records: review and summary for potential users

BACKGROUND

The range and scope of electronic health record (EHR) data assets in the UK has recently increased, which has been mainly in response to the COVID-19 pandemic. Summarising and comparing the large primary care resources will help researchers to choose the data resources most suited to their needs.

AIM

To describe the current landscape of UK EHR databases and considerations of access and use of these resources relevant to researchers.

DESIGN & SETTING

Narrative review of EHR databases in the UK.

METHOD

Information was collected from the Health Data Research Innovation Gateway, publicly available websites and other published data, and from key informants. The eligibility criteria were population-based open-access databases sampling EHRs across the whole population of one or more countries in the UK. Published database characteristics were extracted and summarised, and these were corroborated with resource providers. Results were synthesised narratively.

RESULTS

Nine large national primary care EHR data resources were identified and summarised. These resources are enhanced by linkage to other administrative data to a varying extent. Resources are mainly intended to support observational research, although some can support experimental studies. There is considerable overlap of populations covered. While all resources are accessible to bona fide researchers, access mechanisms, costs, timescales, and other considerations vary across databases.

CONCLUSION

Researchers are currently able to access primary care EHR data from several sources. Choice of data resource is likely to be driven by project needs and access considerations. The landscape of data resources based on primary care EHRs in the UK continues to evolve.

Mortality among individuals prescribed opioid-agonist therapy in Scotland, UK, 2011-20: a national retrospective cohort study

BACKGROUND

Drug-related death (DRD) rate in Scotland, UK, has increased rapidly to one of the highest in the world. Our aim was to examine the extent to which opioid-agonist therapy (OAT) in Scotland is protective against drug-related mortality and how this effect has varied over time.

METHODS

We included individuals in Scotland with opioid use disorder who received at least one OAT prescription between Jan 1, 2011, and Dec 31, 2020. We calculated drug-related mortality rates and used Quasi-Poisson regression models to estimate trends over time and by OAT exposure, adjusting for potential confounding.

FINDINGS

In a cohort of 46 453 individuals prescribed OAT with a total of 304 000 person-years of follow-up, DRD rates more than trebled from 6·36 per 1000 person-years (95% CI 5·73-7·01) in 2011-12 to 21·45 (20·31-22·63) in 2019-20. DRD rates were almost three and a half times higher (hazard ratio 3·37; 95% CI 1·74-6·53) for those off OAT compared with those on OAT after adjustment for confounders. However, confounder adjusted DRD risk increased over time for both people off and on OAT.

INTERPRETATION

Drug-related mortality rates among people with opioid use disorders in Scotland increased between 2011 and 2020. OAT remains protective but is insufficient on its own to slow the increase in DRD risk for people who are opioid dependent in Scotland.

FUNDING

Scottish Government Drug Deaths Taskforce, Public Health Scotland, and National Institute for Health and Care Research.

"Take up to eight tablets per day": Incorporating free-text medication instructions into a transparent and reproducible process for preparing drug exposure data for pharmacoepidemiology

PURPOSE

Routinely collected prescription data provides drug exposure information for pharmacoepidemiology, informing start/stop dates and dosage. Prescribing information includes structured data and unstructured free-text instructions, which can include inherent variability, such as "one to two tablets up to four times a day". Preparing drug exposure data from raw prescriptions to a research ready dataset is rarely fully reported, yet assumptions have considerable implications for pharmacoepidemiology. This may have bigger consequences for "pro re nata" (PRN) drugs. Our aim was, using a worked example of opioids and fracture risk, to examine the impact of incorporating narrative prescribing instructions and subsequent drug preparation assumptions on adverse event rates.

METHODS

R-packages for extracting free-text medication prescription instructions in a structured form (doseminer) and an algorithm for transparently processing drug exposure information (drugprepr) were developed. Clinical Practice Research Datalink GOLD was used to define a cohort of adult new opioid users without prior cancer. A retrospective cohort study was performed using data between January 1, 2017 and July 31, 2018. We tested the impact of varying drug preparation assumptions by estimating the risk of opioids on fracture risk using Cox proportional hazards models.

RESULTS

During the study window, 60 394 patients were identified with 190 754 opioid prescriptions. Free-text prescribing instruction variability, where there was flexibility in the number of tablets to be administered, was present in 42% prescriptions. Variations in the decisions made during preparing raw data for analysis led to marked differences impacting the event number (n = 303-415) and person years of drug exposure (5619-9832). The distribution of hazard ratios as a function of the decisions ranged from 2.71 (95% CI: 2.31, 3.18) to 3.24 (2.76, 3.82).

CONCLUSIONS

Assumptions made during the drug preparation process, especially for those with variability in prescription instructions, can impact results of subsequent risk estimates. The developed R packages can improve transparency related to drug preparation assumptions, in line with best practice advocated by international pharmacoepidemiology guidelines.

Risk of Experiencing an Overdose Event for Patients Undergoing Treatment With Medication for Opioid Use Disorder

OBJECTIVE

Overdose risk during a course of treatment with medication for opioid use disorder (MOUD) has not been clearly delineated. The authors sought to address this gap by leveraging a new data set from three large pragmatic clinical trials of MOUD.

METHODS

Adverse event logs, including overdose events, from the three trials (N=2,199) were harmonized, and the overall risk of having an overdose event in the 24 weeks after randomization was compared for each study arm (one methadone, one naltrexone, and three buprenorphine groups), using survival analysis with time-dependent Cox proportional hazard models.

RESULTS

By week 24, 39 participants had ≥1 overdose event. The observed frequency of having an overdose event was 15 (5.30%) among 283 patients assigned to naltrexone, eight (1.51%) among 529 patients assigned to methadone, and 16 (1.15%) among 1,387 patients assigned to buprenorphine. Notably, 27.9% of patients assigned to extended-release naltrexone never initiated the medication, and their overdose rate was 8.9% (7/79), compared with 3.9% (8/204) among those who initiated naltrexone. Controlling for sociodemographic and time-varying medication adherence variables and baseline substance use, a proportional hazard model did not show a significant effect of naltrexone assignment. Significantly higher probabilities of experiencing an overdose event were observed among patients with baseline benzodiazepine use (hazard ratio=3.36, 95% CI=1.76, 6.42) and those who either were never inducted on their assigned study medication (hazard ratio=6.64, 95% CI=2.12, 19.54) or stopped their medication after initial induction (hazard ratio=4.04, 95% CI=1.54, 10.65).

CONCLUSIONS

Among patients with opioid use disorder seeking medication treatment, the risk of overdose events over the next 24 weeks is elevated among those who fail to initiate or discontinue medication and those who report benzodiazepine use at baseline.

The association between buprenorphine treatment duration and mortality: a multi-site cohort study of people who discontinued treatment

BACKGROUND AND AIMS

Buprenorphine is an effective medication for opioid use disorder that reduces mortality; however, many patients are not retained in buprenorphine treatment, and an optimal length of treatment after which patients can safely discontinue treatment has not been identified. This study measured the association between buprenorphine treatment duration and all-cause mortality among patients who discontinued treatment. Secondary objectives were to measure the association between treatment duration and drug overdose and opioid-related overdoses.

DESIGN

Multi-site cohort study.

SETTING

Eight US health systems.

PARTICIPANTS

Patients who initiated and discontinued buprenorphine treatment between 1 January 2012 and 31 December 2018 (n = 6550). Outcomes occurring after patients discontinued buprenorphine treatment were compared between patients who initiated and discontinued treatment after 8-30, 31-90, 91-180, 181-365 and > 365 days.

MEASUREMENTS

Covariate data were obtained from electronic health records (EHRs). Mortality outcomes were derived from EHRs and state vital statistics. Non-fatal opioid and drug overdoses were obtained from diagnostic codes. Four sites provided cause-of-death data to identify fatal drug and opioid-related overdoses. Adjusted frailty regression was conducted on a propensity-weighted cohort to assess associations between duration of the final treatment episode and outcomes.

FINDINGS

The mortality rate after buprenorphine treatment was 1.82 per 100 person-years (n = 191 deaths). In regression analyses with > 365 days as the reference group, treatment duration was not associated with all-cause mortality and drug overdose (P > 0.05 for both). However, compared with > 365 days of treatment, 91-180 days of treatment was associated with increased opioid overdose risk (hazard ratio = 2.94, 95% confidence interval = 1.11-7.79).

CONCLUSIONS

Among patients who discontinue buprenorphine treatment, there appears to be no treatment duration period associated with a reduced risk for all-cause mortality. Patients who discontinue buprenorphine treatment after 91-180 days appear to be at heightened risk for opioid overdose compared with patients who discontinue after > 365 days of treatment.

Modelling the contribution of incarceration and public health oriented drug law reform to HCV transmission and elimination among PWID in Tijuana, Mexico

BACKGROUND

Incarceration is associated with increased risk of hepatitis C virus (HCV) among people who inject drugs (PWID). Mexico's previous attempt in implementing a public health-oriented drug law reform resulted in minimal impact on incarceration among PWID. However, implementation of reforms alongside Mexico's HCV elimination program has the potential to reshape the HCV epidemic among PWID in the next decade. We use data from a cohort of PWID in Tijuana, Mexico, to inform epidemic modeling to assess the contribution of incarceration and fully implemented drug reform on HCV transmission and elimination among PWID.

METHODS

We developed a dynamic, deterministic model of incarceration, HCV transmission and disease progression among PWID. The model was calibrated to data from Tijuana, Mexico, with 90% HCV seroprevalence among 10,000 PWID. We estimated the 10-year population attributable fraction (PAF) of incarceration to HCV incidence among PWID and simulated, from 2022, the potential impact of the following scenarios: 1) decriminalization (80% reduction in incarceration rates); 2) fully implemented drug law reform (decriminalization and diversion to opiate agonist therapy [OAT]); 3) fully implemented drug law reform with HCV treatment (direct-acting antivirals [DAA]). We also assessed the number DAA needed to reach the 80% incidence reduction target by 2030 under these scenarios.

RESULTS

Projections suggest a PAF of incarceration to HCV incidence of 5.4% (95% uncertainty interval [UI]:0.6-11.9%) among PWID in Tijuana between 2022-2032. Fully implemented drug reforms could reduce HCV incidence rate by 10.6% (95%UI:3.1-19.2%) across 10 years and reduce the number of DAA required to achieve Mexico's HCV incidence reduction goal by 14.3% (95%UI:5.3-17.1%).

CONCLUSIONS

Among PWID in Tijuana, Mexico, incarceration remains an important contributor to HCV transmission. Full implementation of public health-oriented drug law reform could play an important role in reducing HCV incidence and improve the feasibility of reaching the HCV incidence elimination target by 2030.

Analysis of the UK Government's 10-Year Drugs Strategy-a resource for practitioners and policymakers

In 2021, during a drug-related death crisis in the UK, the Government published its ten-year drugs strategy. This article, written in collaboration with the Faculty of Public Health and the Association of Directors of Public Health, assesses whether this Strategy is evidence-based and consistent with international calls to promote public health approaches to drugs, which put 'people, health and human rights at the centre'. Elements of the Strategy are welcome, including the promise of significant funding for drug treatment services, the effects of which will depend on how it is utilized by services and local commissioners and whether it is sustained. However, unevidenced and harmful measures to deter drug use by means of punishment continue to be promoted, which will have deleterious impacts on people who use drugs. An effective public health approach to drugs should tackle population-level risk factors, which may predispose to harmful patterns of drug use, including adverse childhood experiences and socioeconomic deprivation, and institute evidence-based measures to mitigate drug-related harm. This would likely be more effective, and just, than the continuation of policies rooted in enforcement. A more dramatic re-orientation of UK drug policy than that offered by the Strategy is overdue.

Prescribing Characteristics Associated With Opioid Overdose Following Buprenorphine Taper

IMPORTANCE

Retention in buprenorphine therapy is associated with a lower risk of opioid overdose. Nevertheless, many patients discontinue treatment, and there is limited evidence to guide buprenorphine tapering.

OBJECTIVE

To understand what prescribing characteristics are associated with opioid overdose following buprenorphine taper.

DESIGN, SETTING, AND PARTICIPANTS

This is a population-based, retrospective, cohort study of adults who were maintained on buprenorphine for at least 60 days and underwent a buprenorphine taper. The study was conducted in the Canadian province of Ontario, using linked administrative health data. New buprenorphine treatment episodes were accrued between January 1, 2013, and January 1, 2019, and the maximum follow-up was April 30, 2020. Data analysis was performed from December 2020 to August 2022.

EXPOSURES

The primary exposure of interest was time to taper initiation (≤1 year vs >1 year). Secondary exposures included mean rate of taper, percentage days during which the dose was decreasing, and taper duration.

MAIN OUTCOMES AND MEASURES

The primary outcome measure was time to fatal or nonfatal opioid overdose within 18 months following treatment discontinuation.

RESULTS

Among 5774 individuals, the median (IQR) age at index date was 34 (28-44) years, and 3462 individuals (60.0%) were male. Time to taper initiation longer than 1 year vs 1 year or less (6.73 vs 10.35 overdoses per 100 person-years; adjusted hazard ratio [aHR], 0.69; 95% CI, 0.48-0.997), a lower mean rate of taper (≤2 mg per month, 6.95 overdoses per 100 person-years; >2 to ≤4 mg per month, 11.48 overdoses per 100 person-years; >4 mg per month, 17.27 overdoses per 100 person-years; ≤2 mg per month vs >4 mg per month, aHR, 0.65; 95% CI, 0.46-0.91; >2 to ≤4 mg per month vs >4 mg per month, aHR, 0.69; 95% CI, 0.51-0.93), and dose decreases in 1.75% or less of days vs more than 3.50% of days during the taper period (5.87 vs 13.87 overdoses per 100 person-years; aHR, 0.64; 95% CI, 0.43-0.93) were associated with reduced risk of opioid overdose; however, taper duration was not.

CONCLUSIONS AND RELEVANCE

In this retrospective cohort study, buprenorphine tapers undertaken after at least 1 year of therapy, a slower rate of taper, and a lower percentage of days during which the dose was decreasing were associated with a significantly lower risk of opioid overdose, regardless of taper duration. These findings underscore the importance of a carefully planned taper and could contribute to reduction in opioid-related overdose death.

Characteristics of non-fatal overdoses and associated risk factors in patients attending a specialist community-based substance misuse service

Introduction

There are concerns about rising drug-related deaths and the potential contribution of prescription analgesics. There is limited understanding regarding the role of prescription analgesics in non-fatal overdoses (NFODs), nor is there a good understanding of what factors are associated with more severe overdose.

Objectives

To explore risk factors and characteristics of NFODs among people attending a specialist community-based substance misuse service.

Methods

After Caldicott approval, data on NFODs, in people attending the Tayside Substance Misuse Service (TSMS), were extracted from the Scottish Ambulance Service database, along with opioid replacement therapy (ORT) prescribing data. Statistical analysis was performed using R studio and Microsoft Excel.

Results

557 people (78% [434/556] male, mean age ± standard deviation 38.4 ± 7.95) had an NFOD. Repeat NFODs were more likely in males compared to females (p < .0065). Males were more likely to be administered naloxone (OR = 1.94, 95% CI = 1.10-3.40, p < .02). NFODs at home were more likely to be moderate to severe (categorized by Glasgow Comma Scale [p < .02, OR = 4.95, 95% CI = 1.24-24.38]). Methadone (321/557, 57.63%), benzodiazepines (281/557, 50.45%) and heroin (244/557, 43.81%) were the commonest substances: prescribed methadone overdose was more likely than buprenorphine (p < .00001). Opioids and benzodiazepines were often taken together (275/557, 49.40%), with almost all gabapentinoid NFODs also involving opioids (60/61, 98.40%).

Conclusions

Polysubstance use with opioids prescribed for ORT, such as methadone, is highly likely to be implicated in NFOD, with males being at the highest risk of severe and repeat NFOD. Future work should focus on strategies to further reduce NFODs.

Using primary care databases for addiction research: An introduction and overview of strengths and weaknesses

Primary care databases extract and combine routine data from the electronic patient records of various participating practices on a regular basis. These databases can be used for innovative and relevant addiction research, but such use requires a thorough understanding of how data were originally collected and how they need to be processed and statistically analysed to produce sound scientific evidence. The aims of this paper are therefore to (1) make a case for why primary care databases should be considered more frequently for addiction research; (2) provide an overview of how primary care databases are constructed; (3) highlight important methodological and statistical strengths and weaknesses of using primary care databases for research; and (4) give practical advice about how a researcher can get access to databases. Three major primary care databases from the UK serve as examples: Clinical Practice Research Datalink (CPRD), The Health Improvement Network (THIN), and QResearch.

Modeling the population-level impact of opioid agonist treatment on mortality among people accessing treatment between 2001 and 2020 in New South Wales, Australia

BACKGROUND AND AIMS

The individual-level effectiveness of opioid agonist treatment (OAT) in reducing mortality is well established, but there is less evidence on population-level benefits. We use modeling informed with linked data from the OAT program in New South Wales (NSW), Australia, to estimate the impact of OAT provision in the community and prisons on mortality and the impact of eliminating excess mortality during OAT initiation/discontinuation.

DESIGN

Dynamic modeling.

SETTING AND PARTICIPANTS

A cohort of 49 359 individuals who ever received OAT in NSW from 2001 to 2018.

MEASUREMENTS

Receipt of OAT was represented through five stages: (i) first month on OAT, (ii) short (1-9 months) and (iii) longer (9+ months) duration on OAT, (iv) first month following OAT discontinuation and (v) rest of time following OAT discontinuation. Incarceration was represented as four strata: (i) never or not incarcerated in the past year, (ii) currently incarcerated, (iii) released from prison within the past month and (iv) released from prison 1-12 months ago. The model incorporated elevated mortality post-release from prison and OAT impact on reducing mortality and incarceration.

FINDINGS

Among the cohort, mortality was 0.9 per 100 person-years, OAT coverage and retention remained high (> 50%, 1.74 years/episode). During 2001-20, we estimate that OAT provision reduced overdose and other cause mortality among the cohort by 52.8% [95% credible interval (CrI) = 49.4-56.9%] and 26.6% (95% CrI =22.1-30.5%), respectively. We estimate 1.2 deaths averted and 9.7 life-years gained per 100 person-years on OAT. Prison OAT with post-release OAT-linkage accounted for 12.4% (95% CrI = 11.5-13.5%) of all deaths averted by the OAT program, primarily through preventing deaths in the first month post-release. Preventing elevated mortality during OAT initiation and discontinuation could have averted up to 1.4% (95% CrI =  0.8-2.0%) and 3.0% (95% CrI = 2.1-5.3%) of deaths, respectively.

CONCLUSION

The community and prison opioid agonist treatment program in New South Wales, Australia appears to have substantially reduced population-level overdose and all-cause mortality in the past 20 years, partially due to high retention.

Self-harm and suicide during and after opioid agonist treatment among primary care patients in England: a cohort study

BACKGROUND

The first 4 weeks after initiation and cessation of opioid agonist treatment for opioid dependence are associated with an increased risk of all-cause mortality and overdose. We aimed to investigate whether the rate of self-harm and suicide among people who were prescribed opioid agonist treatment differs during initiation, cessation, and the remainder of time on and off treatment.

METHODS

We did a retrospective cohort study and used health-care records from UK Clinical Practice Research Datalink, linked to mortality and hospital admission data, for adults (age 18-75 years at cohort entry) who were prescribed opioid agonist treatment at least once in primary care in England between Jan 2, 1998, and Nov 30, 2018. We estimated rates and adjusted risk ratios (aRRs) of hospital admissions for self-harm and death by suicide, comparing time during and after treatment, as well as comparing stable periods of time on treatment with treatment initiation, cessation, and the remaining time off treatment.

FINDINGS

Between Jan 2, 1998, and Nov 30, 2018, 8070 patients (5594 [69·3%] men and 2476 [30·7%] women) received 17 004 episodes of opioid agonist treatment over 40 599 person-years. Patients were mostly of White ethnicity (7006 [86·8%] patients). 807 episodes of self-harm (1·99 per 100 person-years) and 46 suicides (0·11 per 100 person-years) occurred during the study period. The overall age-standardised and sex-standardised mortality ratio for suicide was 7·5 times (95% CI 5·5-10·0) higher in the study cohort than in the general population. Opioid agonist treatment was associated with a reduced risk of self-harm (aRR in periods off treatment 1·50 [95% CI 1·21-1·88]), but was not significantly associated with suicide risk (aRR in periods off treatment 1·21 [0·64-2·28]). Risk of self-harm (aRR 2·60 [95% CI 1·83-3·70]) and suicide (4·68 [1·63-13·42]) were both elevated in the first 4 weeks after stopping opioid agonist treatment compared with stable periods on treatment.

INTERPRETATION

Stable periods of opioid agonist treatment are associated with reduced risk of self-harm, emphasising the importance of improving retention of patients in treatment. The first month following cessation of opioid agonist treatment is a period of increased risk of suicide and self-harm, during which additional psychosocial support is required.

FUNDING

Medical Research Council.

Assessing the determinants of completing OAT induction and long-term retention: A population-based study in British Columbia, Canada

BACKGROUND

Pharmacological treatments for opioid use disorder are essential, life-saving medications, yet successful induction of them and long-term retention on them is limited in many settings. Induction into opioid agonist treatment (OAT) features the highest risk of mortality throughout the treatment course, and greatest risk of discontinuation. We aimed to identify determinants of completing OAT induction and, among those completing induction, time to OAT discontinuation in British Columbia (BC), Canada.

METHODS

We conducted a retrospective study using linked population-level health administrative databases to capture all individuals in BC receiving at least one OAT dispensation from January 1, 2008, to September 30, 2018. We constructed covariates capturing client demographics, clinical history, and characteristics of the treatment episode and the primary prescribing physician. We estimated a two-part model to identify determinants of the probability of completing induction using a generalized linear mixed model with logit link and the time to OAT discontinuation among those completing induction using a Cox proportional hazards frailty model.

RESULTS

We observed 220,474 OAT episodes (73.9% initiated with methadone, 24.7% with buprenorphine, and 1.4% with slow-release oral morphine) among 45,608 individuals over the study period. Less than 60% of all OAT episodes completed induction (59.0% for methadone episodes, 56.7% for buprenorphine/naloxone, 41.0% for slow-release oral morphine) and half of all episodes that completed induction reached the minimum effective dosage (51.0% for methadone episodes [60 mg/day], 48.2% for buprenorphine/naloxone [12 mg/day], 59.4% for slow-release oral morphine [240 mg/day]). In multiple regression analysis, the adjusted odds of completing induction with buprenorphine improved over time, exceeding that of methadone in 2018: 1.46 (1.40, 1.51). For those who completed induction, buprenorphine use was associated with shorter times to discontinuation throughout the study period, but the estimated rate of discontinuation decreased over time (adjusted hazard ratio, vs. methadone in 2008: 2.50 (2.35, 2.66); in 2018: 1.79 (1.74, 1.85)).

CONCLUSION

We found low rates of completing OAT induction and, for those who did complete it, low rates of reaching the minimum effective dose.

Factors Associated with Long-Term Retention in Buprenorphine-Based Addiction Treatment Programs: a Systematic Review

BACKGROUND

The average length of buprenorphine treatment for opioid use disorder is less than 6 months.

OBJECTIVE

We conducted a systematic review to determine what factors were associated with longer retention in buprenorphine treatment.

DESIGN

We searched Medline, Embase, and Cochrane Database of Systematic Reviews in February 2018. Articles were restricted to randomized controlled trials on human subjects, written in English, which contained ≥ 24 weeks of objective data on retention in buprenorphine treatment.

MAIN MEASURES

We assessed whether dose of buprenorphine, treatment setting, or co-administration of behavioral therapy was associated with retention rates.

KEY RESULTS

Over 14,000 articles were identified. Thirteen articles (describing 9 studies) met inclusion criteria. Measures of retention varied widely. Three studies compared doses of buprenorphine between 1 and 8 mg and showed significantly higher rates of retention with higher doses (p values < 0.01). All other studies utilized buprenorphine doses between 8 and 24 mg daily, without comparison. No study found a significant difference in retention between buprenorphine alone and buprenorphine plus behavioral therapy (p values > 0.05). Initiating buprenorphine while hospitalized or within criminal justice settings prior to outpatient treatment programs was significantly associated with retention in buprenorphine treatment (p values < 0.01 respectively).

CONCLUSIONS

Setting of treatment initiation and a higher buprenorphine dose are associated with improved long-term treatment retention. More objective data on buprenorphine treatment programs are needed, including a standardized approach to defining retention in buprenorphine treatment programs.

REGISTRATION

This review was registered with PROSPERO (#CRD42019120336) in March 2019.

Transition From Full Mu Opioid Agonists to Buprenorphine in Opioid Dependent Patients-A Critical Review

Methadone, a full opioid agonist at the mu-, kappa-, and delta-receptor, and buprenorphine, a partial agonist at the mu receptor, are first-line medications in opioid maintenance treatment. Transition from methadone to buprenorphine may precipitate withdrawal, and no accepted algorithm for this procedure has been developed. Current treatment strategies recommend transfer from methadone to buprenorphine predominantly in patients at low doses of methadone (30-40 mg/day). There are some reports indicating that transition from higher doses of methadone may be possible. A number of dosing strategies have been proposed to soften withdrawal symptoms and facilitate transfer including use of other opioids or medications and especially microdosing techniques for buprenorphine. The case series and studies available thus far are reviewed.

Pain Management Considerations in Patients with Opioid Use Disorder Requiring Critical Care

The opioid epidemic has resulted in increased opioid-related critical care admissions, presenting challenges in acute pain management. Limited guidance exists in the management of critically ill patients with opioid use disorder (OUD). This narrative review provides the intensive care unit (ICU) clinician with guidance and treatment options, including non-opioid analgesia, for patients receiving medications for opioid use disorder (MOUD) and for patients actively misusing opioids. Verification and continuation of the patient's outpatient MOUD regimen, specifically buprenorphine and methadone formulations, assessment of pain and opioid withdrawal, and treatment of acute pain with non-opioid analgesia, nonpharmacologic strategies, and short-acting opioids as needed, are all essential to adequate management of acute pain in patients with OUD. A multidisciplinary approach to treatment and discharge planning in patients with OUD may be beneficial to engage patients with OUD early in their hospital stay to prevent withdrawal, stabilize their OUD, and to reduce the risk of unplanned discharge and other associated morbidity. This article is protected by copyright. All rights reserved.

Could the 2010 HIV outbreak in Athens, Greece have been prevented? A mathematical modeling study

INTRODUCTION

In 2009 and 2010, Athens, Greece experienced a hepatitis C virus (HCV) and a Human Immunodeficiency Virus (HIV) outbreak among People Who Inject Drugs (PWID), respectively. The HCV outbreak was not detected, while that of HIV was identified in 2011. The integrated HIV-interventions, launched in early 2012, managed to reduce directly the HIV incidence and indirectly the HCV incidence. This study aims to assess what would have been the course of the HIV outbreak and its associated economic consequences if the 2009 HCV outbreak had been detected and integrated interventions had been initiated 1- or 2-years earlier.

METHODS

The model was calibrated to reproduce the observed HIV epidemiological and clinical parameters among PWID of Athens, Greece. We examined the effect of the 1- or 2-years earlier detection scenarios, the 1-year later detection, the non-detection scenario, and compared them to the status quo scenario.

RESULTS

Cumulative HIV cases, under the status-quo scenario during 2009-2019, were 1360 (90% Credible intervals: 290, 2470). If the HCV outbreak had been detected 1- or 2- years earlier, with immediate initiation of integrated interventions, 740 and 1110 HIV cases could be averted by 2019, respectively. Regarding the costs, if there was an efficient notification system to detect the HCV outbreak 1 or 2 years earlier, 35.2-53.2 million euros could be saved compared to the status quo by 2019.

CONCLUSIONS

If the HCV outbreak had been detected and promptly addressed, the HIV outbreak would have been prevented and 35.2-53.2 million euros could have been saved.

Cost-effectiveness of hepatitis C virus (HCV) elimination strategies among people who inject drugs (PWID) in Tijuana, Mexico

BACKGROUND AND AIMS

In Latin America, Mexico was first to launch a hepatitis C virus (HCV) elimination strategy, where people who inject drugs (PWID) are a main risk group for transmission. In Tijuana, HCV seroprevalence among PWID is > 90%, with minimal harm reduction (HR). We evaluated cost-effectiveness of strategies to achieve the incidence elimination target among PWID in Tijuana.

METHODS

Modeling study using a dynamic, cost-effectiveness model of HCV transmission and progression among active and former PWID in Tijuana, to assess the cost-effectiveness of incidence elimination strategies from a health-care provider perspective. The model incorporated PWID transitions between HR stages (no HR, only opioid agonist therapy, only high coverage needle-syringe programs, both). Four strategies that could achieve the incidence target (80% reduction by 2030) were compared with the status quo (no intervention). The strategies incorporated the number of direct-acting anti-viral (DAA) treatments required with: (1) no HR scale-up, (2) HR scale-up from 2019 to 20% coverage among PWID, (3) HR to 40% coverage and (4) HR to 50% coverage. Costs (2019 US$) and health outcomes [disability-adjusted life years (DALYs)] were discounted 3% per year. Mean incremental cost-effectiveness ratios (ICER, $/DALY averted) were compared with one-time per capita gross domestic product (GDP) ($9698 in 2019) and purchasing power parity-adjusted per capita GDP ($4842-13 557) willingness-to-pay (WTP) thresholds.

RESULTS

DAAs alone were the least costly elimination strategy [$173 million, 95% confidence interval (CI) = 126-238 million], but accrued fewer health benefits compared with strategies with HR. DAAs + 50% HR coverage among PWID averted the most DALYs but cost $265 million, 95% CI = 210-335 million). The optimal strategy was DAAs + 50% HR (ICER $6743/DALY averted compared to DAAs only) under the one-time per-capita GDP WTP ($9698).

CONCLUSIONS

A combination of high-coverage harm reduction and hepatitis C virus treatment is the optimal cost-effective strategy to achieve the HCV incidence elimination goal in Mexico.

Facilitators of and barriers to buprenorphine initiation for people with opioid use disorder in the emergency department: protocol for a scoping review

INTRODUCTION

Buprenorphine-naloxone is recommended as a first-line agent for the treatment of opioid use disorder. Although initiation of buprenorphine in the emergency department (ED) is evidence based, barriers to implementation persist. A comprehensive review and critical analysis of both facilitators of and barriers to buprenorphine initiation in ED has yet to be published. Our objectives are (1) to map the implementation of buprenorphine induction pathway literature and synthesise what we know about buprenorphine pathways in EDs and (2) to identify gaps in this literature with respect to barriers and facilitators of implementation.

METHODS AND ANALYSIS

We will conduct a scoping review to comprehensively search the literature, map the evidence and identify gaps in knowledge. The review will adhere to the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols Extension for Scoping Reviews and guidance from the Joanna Briggs Institution for conduct of scoping reviews. We will search Medline, APA, PsycINFO, CINAHL, Embase and IBSS from 1995 to present and the search will be restricted to English and French language publications. Citations will be screened in Covidence by two trained reviewers. Discrepancies will be mediated by consensus. Data will be synthesised using a hybrid, inductive-deductive approach, informed by the Consolidated Framework for Implementation Research as well as critical theory to guide further interpretation.

ETHICS AND DISSEMINATION

This review does not require ethics approval. A group of primary knowledge users, including clinicians and people with lived experience, will be involved in the dissemination of findings including publication in peer-reviewed journals. Results will inform future research, current quality improvement efforts in affiliated hospitals, and aide the creation of a more robust ED response to the escalating overdose crisis.

Transition from methadone to subcutaneous buprenorphine depot in patients with opioid use disorder in custodial setting - a case series

BACKGROUND

Methadone, a full opioid agonist, and buprenorphine, a partial agonist at the opioid receptor, are established first-line medications for opioid maintenance therapy. Transition from methadone to sublingual buprenorphine may precipitate withdrawal and is usually performed only in patients on low dose of methadone (<30-40 mg). Transition from methadone to a novel subcutaneous buprenorphine depot (Buvidal) has not been previously described.

OBJECTIVES

To test the hypothesis that a rapid transition from methadone to buprenorphine depot after a single dose of buprenorphine 4 mg sublingual is safe and well tolerated.

METHODS

Retrospective chart analysis of a case series of seven opioid users under custodial setting (prison) who were switched from methadone to buprenorphine depot (initial dose 16 mg weekly subcutaneously) after an initial test dose of buprenorphine 4 mg sublingual within 48 hours.

RESULTS

Clinical data indicate that a rapid transition from methadone to depot buprenorphine is feasible (six patients within 48 hours, one within 4 days). All patients were successfully switched to buprenorphine depot and the transfer period was completed without dropouts or major medical problems. Further dose adjustments were performed in 4 of 7 patients.

CONCLUSIONS

Transition of opioid users from methadone to buprenorphine depot is feasible and safe via 4 mg buprenorphine sublingual. This procedure may facilitate induction of buprenorphine depot formulations in patients treated with methadone.

Association of Opioid Agonist Treatment With All-Cause Mortality and Specific Causes of Death Among People With Opioid Dependence: A Systematic Review and Meta-analysis

Importance

Mortality among people with opioid dependence is higher than that of the general population. Opioid agonist treatment (OAT) is an effective treatment for opioid dependence; however, there has not yet been a systematic review on the relationship between OAT and specific causes of mortality.

Objective

To estimate the association of time receiving OAT with mortality.

Data Sources

The Embase, MEDLINE, and PsycINFO databases were searched through February 18, 2020, including clinical trial registries and previous Cochrane reviews.

Study Selection

All observational studies that collected data on all-cause or cause-specific mortality among people with opioid dependence while receiving and not receiving OAT were included. Randomized clinical trials (RCTs) were also included.

Data Extraction and Synthesis

This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Data on study, participant, and treatment characteristics were extracted; person-years, all-cause mortality, and cause-specific mortality were calculated. Crude mortality rates and rate ratios (RRs) were pooled using random-effects meta-analyses.

Main Outcomes and Measures

Overall all-cause and cause-specific mortality both by setting and by participant characteristics. Methadone and buprenorphine OAT were evaluated specifically.

Results

Fifteen RCTs including 3852 participants and 36 primary cohort studies including 749 634 participants were analyzed. Among the cohort studies, the rate of all-cause mortality during OAT was more than half of the rate seen during time out of OAT (RR, 0.47; 95% CI, 0.42-0.53). This association was consistent regardless of patient sex, age, geographic location, HIV status, and hepatitis C virus status and whether drugs were taken through injection. Associations were not different for methadone (RR, 0.47; 95% CI, 0.41-0.54) vs buprenorphine (RR, 0.34; 95% CI, 0.26-0.45). There was lower risk of suicide (RR, 0.48; 95% CI, 0.37-0.61), cancer (RR, 0.72; 95% CI, 0.52-0.98), drug-related (RR, 0.41; 95% CI, 0.33-0.52), alcohol-related (RR, 0.59; 95% CI, 0.49-0.72), and cardiovascular-related (RR, 0.69; 95% CI, 0.60-0.79) mortality during OAT. In the first 4 weeks of methadone treatment, rates of all-cause mortality and drug-related poisoning were almost double the rates during the remainder of OAT (RR, 2.01; 95% CI, 1.55-5.09) but not for buprenorphine (RR, 0.58; 95% CI, 0.18-1.85). All-cause mortality was 6 times higher in the 4 weeks after OAT cessation (RR, 6.01; 95% CI, 4.32-8.36), remaining double the rate for the remainder of time not receiving OAT (RR, 1.81; 95% CI, 1.50-2.18). Opioid agonist treatment was associated with a lower risk of mortality during incarceration (RR, 0.06; 95% CI, 0.01-0.46) and after release from incarceration (RR, 0.09; 95% CI, 0.02-0.56).

Conclusions and Relevance

This systematic review and meta-analysis found that OAT was associated with lower rates of mortality. However, access to OAT remains limited, and coverage of OAT remains low. Work to improve access globally may have important population-level benefits.

Association Between Buprenorphine for Opioid Use Disorder and Mortality Risk

INTRODUCTION

Veterans with opioid use disorder have an increased risk of suicide and overdose compared with the general population. Buprenorphine, a U.S. Food and Drug Administration-approved medication to treat opioid use disorder, has shown benefits, including decreased risk of illicit drug use and overdose. This study assesses the mortality outcomes with buprenorphine pharmacotherapy among Veterans up to 5 years from treatment initiation.

METHODS

This was a retrospective cohort study of Veterans receiving buprenorphine (2008-2017) across any Veterans Health Administration facility. Buprenorphine pharmacotherapy was evaluated as a time-varying covariate. The primary outcome was death up to 5 years from treatment initiation by suicide and overdose combined; secondary outcomes included suicide, overdose, opioid-specific overdose, and all-cause death. Secondary analyses included evaluating the risk of mortality in recent discontinuation and effect modification by select characteristics. All analyses were conducted in 2020.

RESULTS

Veterans who were not receiving buprenorphine were 4.33 (adjusted hazard ratio; 95% CI=3.60, 5.21) times more likely to die by suicide/overdose than those receiving buprenorphine pharmacotherapy on any given day, with similar protective associations with treatment across secondary outcomes. The risk of suicide/overdose was highest 8-14 days from treatment discontinuation (adjusted hazard ratio=6.54, 95% CI=4.32, 9.91) than in currently receiving buprenorphine pharmacotherapy. There was no evidence of effect modification by the selected covariates.

CONCLUSIONS

Mortality risk was greater among Veterans who were not receiving buprenorphine pharmacotherapy than among those who were. Providers should consider whether buprenorphine pharmacotherapy, either intermittent or continuous, may provide health benefits for their patients and prevent mortality.

[Opioid Substitution Treatment in Germany: Physicians' View on the Effects of the 3rd Revision of the Narcotic Drugs Prescription Ordinance]

STUDY AIM

Opioid substitution treatment (OST) is the most effective drug treatment for opioid dependence worldwide. This form of therapy is also well established in Germany. Nevertheless, there are gaps in the provision of care, especially in rural areas and some states, due to a decreasing number of physicians involved in implementing the substitution programs. The 3rd revision of the Narcotic Drugs Prescription Ordinance (NDPO), which came into force in 2017, transferred medical therapeutic tasks of OST to the policy-making power of the German Medical Association. This comprehensive reform of the general conditions for OST led to greater legal certainty for this form of treatment. The present study aimed to analyze the effects of the 3rd revision of the Narcotic Drugs Prescription Ordinance from the providers' perspective.

METHODS

Between August and December 2019, a questionnaire on individual experiences with the changes implemented in 3rd revision of the Narcotic Drugs Prescription Ordinance was sent by the Federal Opium Agency and the Associations of Statutory Health Insurance Physicians of the chosen federal states to 2,503 physicians implementing the substitution program in Germany as well as 563 physicians in Hamburg, Bavaria, North Rhine-Westphalia and Saxony who were not or no longer involved in this field of medical practice.The evaluation distinguished between physicians with and without further training in addiction medicine and between urban and rural districts.

RESULTS

The response rate of physicians was 34.1%. The average age was 57.9 (±8.7) years, and 64.5% were male. The most relevant changes of the NDPO revision were found to be no time limit for achieving opioid abstinence (85.3%), new assessment and treatment using additional psychotropic substances (71.0%), extending take-home regulation to a maximum of 30 days (70.0%) and greater legal certainty (66.2%). Widening of consultative care up to 10 patients met with little approval (14.8%); 36.7% did not believe that care of substituted patients was assured either now or in the future.

CONCLUSIONS

The NDPO revisions were considered to be relevant in terms of increased legal certainty and treatment liberties. Information was needed in rural areas, among physicians who carried out substitution therapy without advanced training in addiction medicine and physicians no longer involved in substitution therapy.

Buprenorphine management in the perioperative period: educational review and recommendations from a multisociety expert panel

BACKGROUND

The past two decades have witnessed an epidemic of opioid use disorder (OUD) in the USA, resulting in catastrophic loss of life secondary to opioid overdoses. Medication treatment of opioid use disorder (MOUD) is effective, yet barriers to care continue to result in a large proportion of untreated individuals. Optimal analgesia can be obtained in patients with MOUD within the perioperative period. Anesthesiologists and pain physicians can recommend and consider initiating MOUD in patients with suspected OUD at the point of care; this can serve as a bridge to comprehensive treatment and ultimately save lives.

METHODS

The Board of Directors of the American Society of Regional Anesthesia and Pain Medicine, American Society of Anesthesiologists, American Academy of Pain Medicine, American Society of Addiction Medicine and American Society of Health System Pharmacists approved the creation of a Multisociety Working Group on Opioid Use Disorder, representing the fields of pain medicine, addiction, and pharmacy health sciences. An extensive literature search was performed by members of the working group. Multiple study types were included and reviewed for quality. A modified Delphi process was used to assess the literature and expert opinion for each topic, with 100% consensus being achieved on the statements and each recommendation. The consensus statements were then graded by the committee members using the United States Preventive Services Task Force grading of evidence guidelines. In addition to the consensus recommendations, a narrative overview of buprenorphine, including pharmacology and legal statutes, was performed.

RESULTS

Two core topics were identified for the development of recommendations with >75% consensus as the goal for consensus; however, the working group achieved 100% consensus on both topics. Specific topics included (1) providing recommendations to aid physicians in the management of patients receiving buprenorphine for MOUD in the perioperative setting and (2) providing recommendations to aid physicians in the initiation of buprenorphine in patients with suspected OUD in the perioperative setting.

CONCLUSIONS

To decrease the risk of OUD recurrence, buprenorphine should not be routinely discontinued in the perioperative setting. Buprenorphine can be initiated in untreated patients with OUD and acute pain in the perioperative setting to decrease the risk of opioid recurrence and death from overdose.

Understanding ED Buprenorphine Initiation for Opioid Use Disorder: A Guide for Emergency Nurses

Opioid use disorder is a critical public health problem that continues to broaden in scope, adversely affecting millions of people worldwide. Significant efforts have been made to expand access to medication therapy for opioid use disorder, in particular buprenorphine. As the emergency department is a critical point of access for many patients with opioid use disorder, the initiation of buprenorphine therapy in the emergency department is increasing, and emergency nurses should be familiar with the care of these vulnerable patients. The purpose of this article is to provide a clinical review of opioid use disorder and opioid withdrawal syndrome, medication treatments for opioid use disorder, best clinical practices for ED-initiated buprenorphine therapy, assessment of withdrawal symptoms, discharge considerations, and concerns for special populations. With expanded understanding of opioid use disorder, withdrawal, and available treatments, emergency nurses will be better prepared to deliver and support life-saving treatments for patients and families suffering from this disease. In addition, emergency nurses are well positioned to play an important role in public health advocacy around opioid use disorder, providing critical support for destigmatization and expanded access to safe and efficacious treatments.

Project ECHO and primary care buprenorphine treatment for opioid use disorder: Implementation and clinical outcomes

Background: Our rural health system sought to (1) increase the number of primary care clinicians waivered to prescribe buprenorphine for treatment of opioid use disorder (OUD) and (2) consequently increase the number of our patients receiving this treatment. Methods: We used the Project for Extension for Community Health Outcomes (ECHO) tele-education model as an implementation strategy. We examined the number of clinicians newly waivered, the number of patients treated with buprenorphine, the relationship between clinician engagement with ECHO training and rates of buprenorphine prescribing, and treatment retention at 180 days. Results: The number of clinicians with a waiver and number of patients treated increased during and after ECHO training. There was a moderate correlation between the number of ECHO sessions attended by a clinician and number of their buprenorphine prescriptions (r = 0.50, p = 0.01). The 180-day retention rate was 80.7%. Conclusions: Project ECHO was highly effective for increasing access to this evidence-based treatment. The high retention rate in this rural context indicates that most patients are increasing their likelihood of favorable outcomes.

Switching pharmacies leads to gaps in medication possession in individuals treated with buprenorphine

BACKGROUND

Not all pharmacies stock and dispense buprenorphine, potentially complicating continuous access to care for patients with opioid use disorder (OUD). This may become problematic if a patient's primary pharmacy can no longer provide buprenorphine, and the patient cannot locate a new pharmacy.

OBJECTIVES

To identify how often patients treated with buprenorphine for OUD switch pharmacies and to estimate the association between switching pharmacies and a clinically significant gap in therapy of 7 days or longer.

METHODS

A retrospective repeated measures longitudinal cohort design was used. Patients initiating treatment with a buprenorphine product indicated for OUD were identified from the 2016-2018 Texas Prescription Monitoring Program. The predictor of interest-switching pharmacies-was defined by comparing the dispensaries used between subsequent prescriptions. The outcome of interest was defined as a gap in medication possession of 7 days or longer on the basis of the National Quality Forum's definition of continuity of pharmacotherapy for OUD. A generalized estimating equation approach was used to estimate a repeated measures logistic regression measuring the association between switching pharmacies and a gap in therapy.

RESULTS

Of 13,375 eligible patients, 29.6% switched pharmacies at least once during treatment, and 51.6% of these did so more than once. The median time to initial switch was 30 days (interquartile range: 13-66 days). When patients switched pharmacies, they were significantly more likely to have a gap in therapy of between 7 and 29 days (adjusted odds ratio 1.67 [95% CI 1.57-1.78]).

CONCLUSION

Patients receiving buprenorphine switch pharmacies early and frequently in treatment, which leads to clinically significant gaps in therapy. Although qualitative explanatory work is needed to understand why patients switch pharmacies so often, pharmacists and prescribers must ensure that patients have reliable access to a convenient source of buprenorphine to prevent gaps in therapy.

Treatment of opioid use disorder in primary care

Opioid use disorder (OUD) is a common, treatable chronic disease that can be effectively managed in primary care settings. Untreated OUD is associated with considerable morbidity and mortality-notably, overdose, infectious complications of injecting drug use, and profoundly diminished quality of life. Withdrawal management and medication tapers are ineffective and are associated with increased rates of relapse and death. Pharmacotherapy is the evidence based mainstay of OUD treatment, and many studies support its integration into primary care settings. Evidence is strongest for the opioid agonists buprenorphine and methadone, which randomized controlled trials have shown to decrease illicit opioid use and mortality. Discontinuation of opioid agonist therapy is associated with increased rates of relapse and mortality. Less evidence is available for the opioid antagonist extended release naltrexone, with a meta-analysis of randomized controlled trials showing decreased illicit opioid use but no effect on mortality. Treating OUD in primary care settings is cost effective, improves outcomes for both OUD and other medical comorbidities, and is highly acceptable to patients. Evidence on whether behavioral interventions improve outcomes for patients receiving pharmacotherapy is mixed, with guidelines promoting voluntary engagement in psychosocial supports, including counseling. Further work is needed to promote the integration of OUD treatment into primary care and to overcome regulatory barriers to integrating methadone into primary care treatment in the US.

Healthcare use by people who use illicit opioids (HUPIO): development of a cohort based on electronic primary care records in England

Background: People who use illicit opioids such as heroin have substantial health needs, but there are few longitudinal studies of general health and healthcare in this population. Most research to date has focused on a narrow set of outcomes, including overdoses and HIV or hepatitis infections. We developed and validated a cohort using UK primary care electronic health records (Clinical Practice Research Datalink GOLD and AURUM databases) to facilitate research into healthcare use by people who use illicit opioid use (HUPIO). Methods: Participants are patients in England with primary care records indicating a history of illicit opioid use. We identified codes including prescriptions of opioid agonist therapies (methadone and buprenorphine) and clinical observations such as 'heroin dependence'. We constructed a cohort of patients with at least one of these codes and aged 18-64 at cohort entry, with follow-up between January 1997 and March 2020. We validated the cohort by comparing patient characteristics and mortality rates to other cohorts of people who use illicit opioids, with different recruitment methods. Results: Up to March 2020, the HUPIO cohort included 138,761 patients with a history of illicit opioid use. Demographic characteristics and all-cause mortality were similar to existing cohorts: 69% were male; the median age at index for patients in CPRD AURUM (the database with more included participants) was 35.3 (interquartile range 29.1-42.6); the average age of new cohort entrants increased over time; 76% had records indicating current tobacco smoking; patients disproportionately lived in deprived neighbourhoods; and all-cause mortality risk was 6.6 (95% CI 6.5-6.7) times the general population of England. Conclusions: Primary care data offer new opportunities to study holistic health outcomes and healthcare of this population. The large sample enables investigation of rare outcomes, whilst the availability of linkage to external datasets allows investigation of hospital use, cancer treatment, and mortality.

Evaluation of functional status among patients undergoing maintenance treatments for opioid use disorders

Background

Methadone and buprenorphine are the most prevalent types of opioid maintenance programs in Andalusia. The main objective is comparing the functional status of patients with pharmacological opioid maintenance treatments according to different socio-demographic characteristic, health and disabilities domains and sexual difficulties.

Methods

A total of 593 patients from the Andalusia community, 329 were undergoing methadone treatment and 264 were undergoing buprenorphine treatment. The patients were interviewed by socio-demographic and opioid-related variables, assessed by functioning, disability and health domains (WHODAS 2.0.) and for sexual problems (PRSexDQ-SALSEX).

Results

We found significant differences in the socio-demographic and the opioid-related variables as the onset of opioid use, being on previous maintenance programs, opioid intravenous use, the length of previous maintenance programs, polydrug use and elevated seroprevalence rates (HCV and HIV) between the methadone group and the buprenorphine group. Regarding health and disability domains there were differences in the Understanding and communication domain, Getting around domain, Participation in society domain and in the WHODAS 2.0. simple and complex score, favoring buprenorphine-treated patients. The methadone group referred elevated sexual impairments compared with the buprenorphine group. Opioid-related variables as seroprevalence rates, other previous lifetime maintenance program, the daily opioid dosage and the daily alcohol use are the most discriminative variables between both groups. Participation in society variables and sexual problems were the most important clinical variables in distinguishing the methadone group from the buprenorphine group regarding their functional status.

Conclusions

The methadone group showed higher prevalence in opioid dependence-related variables, elevated disabilities in participation in society activities and sexual problems compared with the buprenorphine group. This study shows the importance of carry out a functional evaluation in the healthcare follow-up, especially in those areas related with social activity and with sexual problems.

What is required for achieving hepatitis C virus elimination in Singapore? A modeling study

BACKGROUND AND AIM

The vast majority of hepatitis C virus (HCV) infection in Singapore is among those with a history of injecting drug use (IDU), yet harm reduction is not available and what is required to achieve the World Health Organization (WHO) HCV elimination targets (80% incidence reduction and 65% mortality reduction by 2030) is unknown. We model the intervention scale-up required to achieve WHO targets in Singapore.

METHODS

A dynamic model of HCV transmission and progression among those with a history of IDU was calibrated to Singapore, a setting with declining IDU and no harm reduction (~11 000 people with IDU history in 2017 and 45% HCV seropositive). We projected HCV treatment scale-up from 2019 required to achieve WHO targets with varying prioritization scenarios, with/without opiate substitution therapy scale-up (to 40% among people who inject drugs [PWID]).

RESULTS

We estimated 3855 (95% confidence interval: 2635-5446) chronically HCV-infected individuals with a history of IDU and 148 (87-284) incident HCV cases in Singapore in 2019. Reaching the HCV incidence target requires 272 (187-384) treatments in 2019, totaling 2444 (1683-3452) across 2019-2030. By prioritizing PWID or PWID and cirrhotics, 60% or 30% fewer treatments are required, respectively, whereas the target cannot be achieved with cirrhosis prioritization. Opiate substitution therapy scale-up reduces treatments required by 21-24%. Achieving both WHO targets requires treating 631 (359-1047) in 2019, totaling 3816 (2664-5423) across 2019-2030.

CONCLUSIONS

Hepatitis C virus elimination is achievable in Singapore but even with declining IDU requires immediate treatment scale-up among PWID. Harm reduction provision reduces treatments required and provides additional benefits.

Allocating treatment resources for hepatitis C in the UK: a constrained optimization modelling approach

Background and objective: Although the treatment of chronic hepatitis C (CHC) has significantly evolved with the introduction of direct-acting antivirals, the treatment uptake rates have been low especially among marginalized groups in the UK, such as people who inject drug (PWID) and men who have sex with men (MSM). Cutting health inequality is a major focus of healthcare agencies. This study aims to identify the optimal allocation of treatment budget for chronic hepatitis CHC among populations and treatments in the UK so that liver-related mortality in patients with CHC is minimized, given the constraint of treatment budget and equity issue. Methods: A constrained optimization modelling of resource allocation for the treatment of CHC was developed in Excel from the perspective of the UK National Health System over a lifetime horizon. The model was designated with the objective function of minimizing liver-related deaths by varying the decision variables, representing the number of patients receiving each treatment (elbasvir-grazoprevir, ombitasvir-paritaprevir-ritonavir-dasabuvir, sofosbuvir-ledipasvir, and pegylated interferon-ribavirin) in each population (the general population, PWID, and MSM). Two main constraints were formulated including treatment budget and the issue of equity. The model was populated with UK local data applying linear programming and underwent internal and external validation. Scenario analyses were performed to assess the robustness of model results. Results: Within the constraints of no additional funding over original spending in status quo and the consideration of the issue of equity among populations, the optimal allocation from the constrained optimization modelling (treating 13,122 PWID, 160 MSM, and 904 general patients with ombitasvir-paritaprevir-ritonavir-dasabuvir) was found to treat 2,430 more patients (relative change: 20.7%) and avert 78 liver-related deaths (relative change: 0.3%) compared with the current allocation. The number of patients receiving treatment increased 4,928 (relative change: 60.1%) among PWID and 42 (relative change: 35.8%) among MSM. Conclusion: The current allocation of treatment budget for CHC is not optimal in the UK. More patients would be treated, and more liver-related deaths would be avoided using a new allocation from a constrained optimization modelling without incurring additional spending and considering the issue of equity.

Retention in the Austrian opioid agonist treatment system: a national prospective cohort study

BACKGROUND

Retention in care is a prerequisite for successful recovery, especially for a chronic condition like opioid dependence. Though retention varies greatly depending on the different substitution medication and treatment model, treatment retention is used as an indicator of treatment quality and effectiveness of care on a system and individual level. To monitor the overall quality of the Austrian opioid agonist treatment (OAT) system and to monitor patient satisfaction within the system, a new online-based registry called "eSuchmittel" was introduced in Austria at the beginning of 2011. The objective of this study is to analyze retention rates within the Austrian treatment system and to identify patient characteristics associated with retention, using data collected by the substitution registry.

METHODS

The complete Austrian sample of 4778 registered patients starting treatment between 1.1.2011 to 31.12.2012 were included in the prospective cohort study using data from the Austrian substitution registry. For the statistical analysis, multivariate Cox Regression and Kaplan-Meier survival analysis were used to evaluate retention in treatment.

RESULTS

The retention rate of the total cohort after two years was around 61%. Retention rates were significantly lower for men (exp(B) = .806, 95% CI 0.714-0.908) and significantly higher for patients aged 30 and older (exp(B) = 1.155, 95% CI 1.044-1.279), among patients located in Vienna (exp(B) = 1.439, 95% CI 1.273-1.626) and among patients prescribed oral slow-release morphine (SROM) (exp(B) = 2.141, 95% CI 1.885-2.430).

CONCLUSIONS

Average retention in the Austrian system is high in comparison to international retention rates. Nationally, SROM demonstrates higher treatment retention when compared to other available substitution medications. Sociodemographic and regional indicators also contribute to higher retention in care. A systematic monitoring of retention rates within a national registry is an important tool helping to evaluate the quality of care. In this study, the Austrian OAT system proves very high retention in care, an important success criterion.

Is hepatitis C virus (HCV) elimination achievable among people who inject drugs in Tijuana, Mexico? A modeling analysis

BACKGROUND

In 2019, Mexico became the first Latin American country committed to hepatitis C virus (HCV) elimination, but the amount of intervention scale-up required is unclear. In Tijuana, HCV among people who inject drugs (PWID) is high; yet there is minimal and intermittent harm reduction, and involuntary exposure to compulsory abstinence programs (CAP) occurs which is associated with increased HCV risk. We determined what combination intervention scale-up can achieve HCV elimination among current and former PWID in Tijuana.

METHODS

We constructed a dynamic, deterministic model of HCV transmission, disease progression, and harm reduction among current and former PWID parameterized to Tijuana (~10,000 current PWID, 90% HCV seropositive, minimal opiate agonist therapy [OAT] or high coverage needle/syringe programs [HCNSP]). We evaluated the number of direct-acting antiviral (DAA) treatments needed from 2019 to achieve elimination targets (80% incidence reduction, 65% mortality reduction by 2030) with: (a) DAAs alone, (b) DAAs plus scale-up of OAT+HCNSP (up to 50% coverage of OAT and HCNSP separately, producing 25% of PWID receiving both), (c) DAAs plus CAP scale-up to 50%. Scenarios examined the number of DAAs required if prioritized to current PWID or provided regardless of current injection status, and impact of harm reduction interruptions.

RESULTS

Modeling suggests among ~30,000 current and former PWID in Tijuana, 16,160 (95%CI: 12,770-21,610) have chronic HCV. DAA scale-up can achieve the incidence target, requiring 770 treatments/year (95%CI: 640-970) if prioritized to current PWID. 40% fewer DAAs are required with OAT+HCNSP scale-up to 50% among PWID, whereas more are required with involuntary CAP scale-up. Both targets can only be achieved through treating both current and former PWID (1,710 treatments/year), and impact is reduced with harm reduction interruptions.

CONCLUSIONS

Elimination targets are achievable in Tijuana through scale-up of harm reduction and DAA therapy, whereas involuntary CAP and harm reduction interruptions hamper elimination.

Factors associated with early and later dropout from methadone maintenance treatment in specialist addiction clinics: a six-year cohort study using proportional hazards frailty models for recurrent treatment episodes

BACKGROUND

Retention in methadone maintenance treatment (MMT) is associated with reduced illicit drug use, criminal activity, and mortality; however, many clients move in and out of MMT. This study aims to identify determinants of time to dropout of MMT across multiple treatment episodes in specialist addiction services in Ireland.

METHODS

Cohort study of persons attending specialist addiction clinics between 2010 and 2015. MMT episodes were periods of continuous treatment if there were no interruptions to treatment lasting > 7days. Proportional hazards frailty models were used to assess factors associated with time to dropout from recurrent MMT episodes at 3 (90 days) and 12 months (91-365 days). MMT episodes were right- censored at time of death, transfer to prison or primary care, and study end.

RESULTS

A total of 2,035 individuals experienced 4,969 MMT episodes, with 2,724 dropout events during the six-year follow-up. Factors associated with dropout at 3 months included low dose methadone (<60 mg/day) (HR = 1.49, 95% CI 1.29-1.73) and previous dropout (HR = 1.65, 95% CI 1.41-1.92). Adherence was protective (HR = 0.91, 95% CI 0.90-0.92). Dropout at 12 months was associated with low dose methadone (HR = 1.44, 95% CI 1.23-1.68), previous dropout (HR = 1.37, 95% CI 1.16-1.61), males (HR 1.26, 95% CI 1.06-1.50), benzodiazepines (HR = 1.22, 95% CI 1.03-1.45) and number of comorbidities (HR = 1.12, 95% CI 1.05-1.20); adherence was protective (HR = 0.86, 95% CI 0.84-0.87).

CONCLUSIONS

Clients with a previous history of treatment dropout and those on low dose methadone should be identified as high risk for both early and later dropout. Inversely, adherence to treatment, not missing methadone doses, is protective.

Healthcare use by people who use illicit opioids (HUPIO): development of a cohort based on electronic primary care records in England

Background: People who use illicit opioids such as heroin have substantial health needs, but there are few longitudinal studies of general health and healthcare in this population. Most research to date has focused on a narrow set of outcomes, including overdoses and HIV or hepatitis infections. We developed and validated a cohort using UK primary care electronic health records (Clinical Practice Research Datalink GOLD and AURUM databases) to facilitate research into healthcare use by people who use illicit opioid use (HUPIO). Methods: Participants are patients in England with primary care records indicating a history of illicit opioid use. We identified codes including prescriptions of opioid agonist therapies (methadone and buprenorphine) and clinical observations such as 'heroin dependence'. We constructed a cohort of patients with at least one of these codes and aged 18-64 at cohort entry, with follow-up between January 1997 and March 2020. We validated the cohort by comparing patient characteristics and mortality rates to other cohorts of people who use illicit opioids, with different recruitment methods. Results: Up to March 2020, the HUPIO cohort included 138,761 patients with a history of illicit opioid use. Demographic characteristics and all-cause mortality were similar to existing cohorts: 69% were male; the median age at index for patients in CPRD AURUM (the database with more included participants) was 35.3 (IQR 29.1-42.6); the average age of new cohort entrants increased over time; 76% had records indicating current tobacco smoking; patients disproportionately lived in deprived neighbourhoods; and all-cause mortality risk was 5.4 (95% CI 5.3-5.5) times the general population of England. Conclusions: Primary care data offer new opportunities to study holistic health outcomes and healthcare of this population. The large sample enables investigation of rare outcomes, whilst the availability of linkage to external datasets allows investigation of hospital use, cancer treatment, and mortality.

Estimating the prevalence of problem drug use from drug-related mortality data

BACKGROUND AND AIMS

Indirect estimation methods are required for estimating the size of populations where only a proportion of individuals are observed directly, such as problem drug users (PDUs). Capture-recapture and multiplier methods are widely used, but have been criticized as subject to bias. We propose a new approach to estimating prevalence of PDU from numbers of fatal drug-related poisonings (fDRPs) using linked databases, addressing the key limitations of simplistic 'mortality multipliers'.

METHODS

Our approach requires linkage of data on a large cohort of known PDUs to mortality registers and summary information concerning additional fDRPs observed outside this cohort. We model fDRP rates among the cohort and assume that rates in unobserved PDUs are equal to rates in the cohort during periods out of treatment. Prevalence is estimated in a Bayesian statistical framework, in which we simultaneously fit regression models to fDRP rates and prevalence, allowing both to vary by demographic factors and the former also by treatment status.

RESULTS

We report a case study analysis, estimating the prevalence of opioid dependence in England in 2008/09, by gender, age group and geographical region. Overall prevalence was estimated as 0.82% (95% credible interval = 0.74-0.94%) of 15-64-year-olds, which is similar to a published estimate based on capture-recapture analysis.

CONCLUSIONS

Our modelling approach estimates prevalence from drug-related mortality data, while addressing the main limitations of simplistic multipliers. This offers an alternative approach for the common situation where available data sources do not meet the strong assumptions required for valid capture-recapture estimation. In a case study analysis, prevalence estimates based on our approach were surprisingly similar to existing capture-recapture estimates but, we argue, are based on a much more objective and justifiable modelling approach.

Treating Perioperative and Acute Pain in Patients on Buprenorphine: Narrative Literature Review and Practice Recommendations

Opioid use disorder (OUD), a leading cause of morbidity and mortality in the USA, can be effectively treated with buprenorphine. However, the same pharmacologic properties (e.g., high affinity, partial agonism, long half-life) that make it ideal as a treatment for OUD often cause concern among clinicians that buprenorphine will prevent effective management of acute pain with full agonist opioid analgesics. Because of this concern, many patients are asked to stop buprenorphine preoperatively or at the onset of acute pain, placing them at high risk for both relapse and a difficult transition back to buprenorphine after acute pain has resolved. The purpose of this review is to summarize the existing literature for acute pain and perioperative management in patients treated with buprenorphine for OUD and to provide practical management recommendations for generalist practitioners based on evidence and clinical experience. In short, evidence suggests that sufficient analgesia can be achieved with maintenance of buprenorphine and use of both opioid and non-opioid analgesic options for breakthrough pain. We recommend that clinicians (1) continue buprenorphine in the perioperative or acute pain period for patients with OUD; (2) use a multi-modal analgesic approach; (3) pay attention to care coordination and discharge planning when making an analgesic plan for patients with OUD treated with buprenorphine; and (4) use an individualized approach founded upon shared decision-making. Clinical examples involving mild and severe pain are discussed to highlight important management principles.

Impact of COVID-19 Related Policy Changes on Buprenorphine Dispensing in Texas

OBJECTIVES

To measure the change in the daily number of patients receiving buprenorphine and buprenorphine prescribers during the early phase of the COVID-19 (SARS-CoV-2) pandemic in Texas.

METHODS

Counts of the number of patients filling and number of providers prescribing buprenorphine were calculated for each weekday between November 4, 2019 and May 12, 2020. The change in daily patients and prescribers between March 2, 2020 and May 12, 2020, was modeled as a change in slope compared to the baseline period using autoregressive, interrupted time series regression.

RESULTS

The rate of change of daily buprenorphine prescriptions (β = -1.75, 95% CI = -5.8-2.34) and prescribers (β = -0.32, 95% CI = -1.47-0.82) declined insignificantly during the COVID-19 period compared to the baseline.

CONCLUSIONS

Despite a 57% decline in ambulatory care utilization in the south-central US during March and April of 2020, health services utilization related to buprenorphine in Texas remained robust. Protecting access to buprenorphine as the COVID-19 pandemic continues to unfold will require intensive efforts from clinicians and policy makers alike. While the presented results are promising, researchers must continue monitoring and exploring the clinical and humanistic impact of COVID-19 on the treatment of substance use disorders.

The cost of a late-detected outbreak among people who inject drugs. A modeling study

BACKGROUND

People who inject drugs (PWID) are at risk for human immunodeficiency virus (HIV) and hepatitis C virus (HCV). In 2009 and 2011, Athens, Greece experienced an HCV and an HIV outbreak among PWID, respectively. Of these, only the 2011 HIV outbreak was detected. However, the public health interventions implemented in response to the HIV outbreak tackled also indirectly the undetected HCV outbreak. The aim of this study is to highlight the potential benefits of an efficient notification system using as a case study the undetected 2009 HCV outbreak among PWID of Athens. More specifically, the study assesses whether an earlier implementation of the same public responses could diminish the scale of the HCV outbreak and estimates the potential cost-savings.

METHODS

A previous dynamic, stochastic, individual-based model was used to simulate HCV transmission among PWID of Athens, Greece. We calibrated the model to reproduce the observed HCV prevalence. We examined the effect of the non-detection scenario, the 1- or 2-years earlier detection scenarios and compared them to the status quo scenario.

RESULTS

Under the non-detection scenario, 2800 additional PWID would have been infected with HCV compared to the status quo by 2019. On the contrary, if the outbreak was detected 1- or 2- years earlier with immediate interventions, 440 and 970 HCV cases could be averted by 2019, respectively. Non-detection of the outbreak would cost an additional 43.2 (95% Credible interval: 2.7, 59.4) million euros to the healthcare system, compared to the status quo. On the other hand, if there was an efficient notification system to detect the HCV outbreak 1 or 2 years earlier, 6.8-15.6 million euros could have been saved by 2019.

CONCLUSIONS

An efficient notification system among PWID is a cost-saving investment that could detect on time and contain future outbreaks, and save valuable resources of the healthcare system.