National record linkage study of mortality for a large cohort of opioid users ascertained by drug treatment or criminal justice sources in England, 2005-2009

Molecular Pharmacology Profiling of Phenylfentanil and Its Analogues to Understand the Putative Involvement of an Adrenergic Mechanism in Fentanyl-Induced Respiratory Depression

While there are approved therapeutics to treat opioid overdoses, the need for treatments to reverse overdoses due to ultrapotent fentanyls remains unmet. This may be due in part to an adrenergic mechanism of fentanyls in addition to their stereotypical mu-opioid receptor (MOR) effects. Herein, we report our efforts to further understanding of the functions these distinct mechanisms impart. Employing the known MOR neutral antagonist phenylfentanil as a lead, 17 analogues were designed based on the concept of isosteric replacement. To probe mechanisms of action, these analogues were pharmacologically evaluated in vitro and in vivo, while in silico modeling studies were also conducted on phenylfentanil. While it did not indicate MOR involvement in vivo, phenylfentanil yielded respiratory minute volumes similar to those caused by fentanyl. Taken together with molecular modeling studies, these results indicated that respiratory effects of fentanyls may also correlate to inhibition of both α1A- and α1B-adrenergic receptors.

Opioid-related deaths and their counterpart by occurrence era, age group and coimplicated drugs: Scotland vs. England and Wales

AIMS

Compare by occurrence era and age group how opioid-related deaths (ORDs) and their counterpart evolved in Scotland vs. England and Wales during 2006-2020. For Scotland, compare coimplication rates between ORDs and non-ORDs for any benzodiazepine, cocaine or gabapentin/pregabalin, and consider whether coimplication in ORDs depended on opioid-specificity.

METHODS

Cross-tabulations of drug misuse deaths (DMDs) obtained by 3 yearly occurrence era (2006-2008 to 2018-2020) and age group (under 25, 25-34, 35-44, 45-54, 55+ years) for England and Wales and subdivided by whether at least 1 opiate was mentioned on death certificate (DMD-Os or not); and of Scotland's opioid-related deaths (ORDs vs. non-ORDs) together with (i) coimplication by any benzodiazepine, cocaine or gabapentin/pregabalin; and (ii) opioid-specificity of ORDs. ORD is defined by heroin/morphine, methadone or buprenorphine being implicated in DMD.

RESULTS

Per era between 2012-2014 and 2018-2020, Scotland's ORDs increased by 54% and non-ORDs by 34%. Increase in DMD-Os in England and Wales was more modest. Cocaine was implicated in 83% of Scotland's 2690 non-ORDs during 2006-2020; and any benzodiazepine in 53% of 8409 ORDs. However, in 2018-2020, coimplication rates in 2926 ORDs (880 non-ORDs) were 81% (33%) for any benzodiazepine, 30% (74%) for cocaine and 38% (22%) for gabapentin/pregabalin. Coimplication rate in 2018-2020 for any benzodiazepine was lowest at 70% (616/877) for heroin/morphine ORDs; and, by age group, at 66% (160/241) for ORDs aged 55+ years.

CONCLUSIONS

Drug testing to inform users, shared intelligence between police and public health for earlier detection of changes in supply and monitoring of prescribed daily-dose of methadone are urgent.

Opioid use disorder in two samples of the Lebanese population: scale validation and correlation with sleep and mood disorders

BACKGROUND

The revised Opioid Risk Tool (ORT-OUD) is a brief, self-report scale designed to provide clinicians with a simple, validated method to screen for the risk of developing an Opioid Use Disorder (OUD) in patients without a prior history of substance abuse. This study aimed to translate and validate the Arabic version of ORT-OUD in the Lebanese population and assess its clinical validity in a sample of patients with OUD.

METHODS

This cross-sectional study in the Lebanese population used several validated scales to assess the risk of OUD, including the Alcohol, Smoking, and Substance Involvement Screening Test (ASSIST). Other tools evaluated chronotype and sleep and mood disturbances. Principal component analysis with Varimax rotation was applied to assess ORT-OUD construct validity. Convergent validity with the Arabic version of ASSIST was evaluated. The ORT-OUD criterion validity was then assessed in a clinical sample of patients with OUD.

RESULTS

This study included 581 participants. The prevalence of the OUD risk in the Lebanese population using the ORT-OUD scale and the ASSIST-opioids scale was estimated at 14.5% and 6.54%, respectively. No items of the ORT-OUD were removed; all items converged over a solution of four factors with an eigenvalue > 1, explaining a total of 68.2% of the variance (Cronbach's alpha = 0.648). The correlation coefficients between the ORT-OUD total score and ASSIST subscales were as follows: ASSIST-opioids (r = 0.174; p = < 0.001), ASSIST-sedatives (r = 0.249; p < 0.001), and ASSIST-alcohol (r = 0.161; p = < 0.001). ORT-OUD clinical validation showed a correlation with ASSIST-opioids (r = 0.251; p = 0.093) and ASSIST-sedatives (r = 0.598; p < 0.001). Higher ORT-OUD scores were associated with a family and personal history of alcohol and substance consumption and higher insomnia and anxiety scores.

CONCLUSIONS

This study is the first to validate the Arabic version of ORT-OUD in the Lebanese population, an essential step towards improving the detection and management of OUD in this population.

[Bronchial diseases and heroin use. A systematic review]

INTRODUCTION

Heroin use can cause respiratory complications including asthma, chronic obstructive pulmonary disease (COPD) and bronchiectasis (BD).

OBJECTIVES

A general review of the literature presenting the data on the relationships between heroin consumption and bronchial complications, while underlining the difficulties of diagnosis and management.

DOCUMENTARY SOURCES

Medline, 1980-2022, keywords "asthma" or "bronchospasm" or "COPD" or "bronchiectasis" and "heroin" or "opiate" or "opiates", with limits pertaining to "Title/Abstract". Concerning asthma, 26 studies were included, as were 16 for COPD and 5 for BD.

RESULTS

Asthma and COPD are more prevalent among heroin addicts, who are less compliant than other patients with their treatment. The authors found a positive association between frequency of asthma exacerbations, admission to intensive care and heroin inhalation. Late diagnosis of COPD worsens the course of the disease; emphysema and BD are poor prognostic factors.

CONCLUSION

Bronchial diseases in heroin users can be identified by means of respiratory function exploration and chest CT scans. These tests should be performed frequently in view of optimizing their care, which includes their weaning themselves from addictive substances.

Overdose and suicide are different phenomena among opioid users that require different clinical management

Given the high rates of mental health comorbidity among opioid users, and increasing rates of opioid prescription for chronic pain, psychiatrists and mental health clinicians are likely to treat patients who are dependent on opioids. Among such patients, many will have histories of opioid overdose or suicide attempts. It is tempting to assume that these are related behaviours and that 'accidental' overdoses are actually suicide attempts. We provide evidence here to demonstrate that while some overdoses are intentional, most are not. More than half of deaths among opioid users are due to unintentional overdose. Suicides constitute a minority: less than 10% of heroin user deaths are estimated to be due to suicide, as are 20-30% of prescribed opioid fatalities. Moreover, suicide attempts are more commonly made using means other than opioids. Overdose and suicide among opioid dependent patients are two distinct phenomena, associated with different risk factors, that need to be separately assessed and their respective risk managed.

Mortality in the SuperMIX cohort of people who inject drugs in Melbourne, Australia: a prospective observational study

AIMS

To measure mortality rates and factors associated with mortality risk among participants in the SuperMIX study, a prospective cohort study of people who inject drugs.

DESIGN

A prospective observational study using self-reported behavioural and linked mortality data.

SETTING

Melbourne, Australia.

PARTICIPANTS/CASES

A total of 1209 people who inject drugs (67% male) followed-up between 2008 and 2019 for 6913 person-years (PY).

MEASUREMENTS

We linked participant identifiers from SuperMIX to the Australian National Death Index and estimated all-cause and drug-related mortality rates and standardized mortality ratios (SMRs). We used Cox regression to examine associations between mortality and fixed and time-varying socio-demographic, alcohol and other drug use and health service-related exposures.

FINDINGS

Between 2008 and 2019 there were 76 deaths in the SuperMIX cohort. Of those with a known cause of death (n = 68), 35 (51%) were drug-related, yielding an all-cause mortality rate of 1.1 per 100 PY [95% confidence interval (CI) = 0.88-1.37] with an estimated SMR of 16.64 (95% CI = 13.29-20.83) and overall accidental drug-induced mortality rate of 0.5 per 100 PY (95% CI = 0.36-0.71). Reports of recent use of ambulance services [adjusted hazard ratio (aHR) = 3.77, 95% CI =1.78-7.97] and four or more incarcerations (aHR = 2.78, 95% CI = 1.55-4.99) were associated with increased mortality risk.

CONCLUSIONS

In Melbourne, Australia, mortality among people who inject drugs appears to be positively associated with recent ambulance attendance and experience of incarceration.

Non-fatal overdose risk during and after opioid agonist treatment: A primary care cohort study with linked hospitalisation and mortality records

Background

The initiation and cessation of opioid agonist treatment (OAT) have both been associated with elevated risk of fatal overdose. We examined risk of non-fatal overdose during OAT initiation and cessation and specifically between methadone versus buprenorphine recipients.

Methods

We utilised primary care electronic health records from the Clinical Practice Research Datalink to delineate a study cohort of adults aged 18-64 who were prescribed OAT between Jan 1, 1998 and Dec 31, 2017. These records were linked to hospitalisation, mortality records and patient neighbourhood and practice-level Index of Multiple Deprivation quintiles. With inverse probability treatment weights applied and negative binomial regression models we estimated incidence rate ratios for hospital admissions among patients who experienced multiple overdoses.

Findings

A total of 20898 patients were prescribed methadone or buprenorphine over 83856 person-years of follow-up. Compared with periods in treatment, patients not in treatment were 51% more likely to experience a non-fatal overdose that required hospitalisation (weighted rate ratio, wRR 1·51; 95% CI 1·42, 1·60), especially during the four weeks of OAT initiation (5·59; 5·31, 5·89) and following cessation (13·39; 12·78, 14·03). The wRR of overdose during (0·37; 0·34, 0·39) and after treatment (0·36; 0·34, 0·38) favoured buprenorphine compared to methadone.

Interpretation

OAT is associated with decreased non-fatal overdose risk. Buprenorphine may act more protectively than methadone, especially during the first four weeks of treatment.

Funding

National Institute for Health and Care Research (NIHR) Greater Manchester Patient Safety Translational Research Centre (PSTRC-2016-003).

Burden and treatment of chronic obstructive pulmonary disease among people using illicit opioids: matched cohort study in England

Objective

To understand the burden of chronic obstructive pulmonary disease among people who use illicit opioids such as heroin, and evaluate inequalities in treatment.

Design

Cohort study.

Setting

Patients registered at primary care practices in England.

Participants

106 789 patients in the Clinical Practice Research Datalink with illicit opioid use recorded between 2001 and 2018, and a subcohort of 3903 patients with a diagnosis of chronic obstructive pulmonary disease. For both cohorts, the study sampled a comparison group with no history of illicit opioids that was matched by age, sex, and general practice.

Main outcome measures

In the base cohort: diagnosis of chronic obstructive pulmonary disease and death due to the disease. In the subcohort: five treatments (influenza vaccine, pneumococcal vaccine, pulmonary rehabilitation, bronchodilators or corticosteroids, and smoking cessation support) and exacerbations requiring hospital admission.

Results

680 of 106 789 participants died due to chronic obstructive pulmonary disease, representing 5.1% of all cause deaths. Illicit opioid use was associated with 14.59 times (95% confidence interval 12.28 to 17.33) the risk of death related to chronic obstructive pulmonary disease, and 5.89 times (5.62 to 6.18) the risk of a diagnosis of the disease. Among patients with a new diagnosis, comorbid illicit opioid use was associated with current smoking, underweight, worse lung function, and more severe breathlessness. After adjusting for these differences, illicit opioids were associated with 1.96 times (1.82 to 2.12) times the risk of exacerbations requiring hospital admission, but not associated with a substantially different probability of the five treatments.

Conclusions

Death due to chronic obstructive pulmonary disease is about 15 times more common among people who use illicit opioids than the general population. This inequality does not appear to be explained by differences in treatment, but late diagnosis of the disease among people who use illicit opioids might contribute.

Distinguishing clinical factors associated with unintentional overdose, suicidal ideation, and attempted suicide among opioid use disorder in-patients

Opioid and other drug-related overdoses and suicides are leading causes of injury death and represent a significant public health threat in the United States (U.S.). This study examined clinical factors of three patient groups from two inpatient addiction treatment facilities in Appalachian West Virginia (n = 66). Patients were classified as having: 1) unintentional overdose(s) (OD), 2) suicidal ideation or suicide attempt(s) (SI/SA), and 3) suicidal ideation or suicide attempt, and unintentional overdose (SI/SA/OD). Multinomial logistic regression models were used to determine whether adverse childhood experiences, self-injurious behaviors, substance use history, overdose history, and past year stressful life events were differentially associated with history of SI/SA/OD. Participants in the OD group were more likely to have used heroin in the 24-h preceding their most recent overdose compared to either the SI/SA or SI/SA/OD groups. The multivariable model found participants with history of SI/SA had higher adverse childhood experience scores and more participants with history of SI/SA endorsed childhood physical abuse and teen dating violence. Overall, there are characteristics that distinguish unintentional overdose from suicidal ideation and attempt. Patients with SI/SA/OD appear to have greater clinical severity. More thorough evaluation of drugs involved in overdose and history of self-injury may help distinguish future risk and inform treatment planning.

Longitudinal Patterns of Suicidality Among Heroin Users in Johannesburg, South Africa: A Need for Suicide Screening and Intervention

Objectives

The objective of the study was to longitudinally assess the outcomes and correlates of suicidal ideation and behavior (SIB) among heroin users who attended inpatient detoxification and psychosocial rehabilitation. SIB was assessed in 300 heroin users upon entry into inpatient detoxification (baseline) as well as 3-months (t1) (n = 252; 84%) and 9-months (t2) (n = 225; 75%) post treatment. Multivariable logistic regression was used to determine the demographic, clinical and treatment related factors that increased the risk for a high SIB score.

Results

From baseline to t1 there was a significant decrease in the proportion of those who endorsed SIB (68.7 vs. 38.9%, p < 0.0001). There was an increase in the proportion of those who endorsed SIB from t1 to t2 (38,9 vs. 47.1%, p = 0.047). There was a significant increase in the proportion of those reporting suicide likely in the near future from baseline to t1 (8.7 vs. 16.3%: p < 0.0049) and this was repeated from t1 to t2 (22.7%) (t1 vs. t2: p = 0.031). After controlling for all other variables, a comorbid mental illness (MI) at baseline was a significant independent risk factor for a high SIB score at t1(RR 1.63; 95% CL 1.30-2.03) (p < 0.0001) and a comorbid MI at t1 increased the risk for a high SIB score at t2 (RR 2.73; 95% CL 1.78-4.19) (p < 0.0001). A poorer general health score and poorer social functioning score at baseline were associated with a high SIB score at baseline (RR 1.02; 95% CL 1.01-1.04) (p = 0.001) and t2, respectively (RR 1.07; 95% CL 1.04-1.11) (p < 0.0001).

Conclusions

Among heroin users, a comorbid mental illness, poorer physical health and poorer social functioning are important factors to consider in suicide risk assessment. Although there were decreases in overall SIB 3 months after detoxification, this trend was not sustained at 9-month follow-up. After detoxification there were significant increases in the proportion of those reporting a likelihood of suicide in the following 3 months. The results suggests that the treatment exposure did not adequately mitigate suicide risk. There is a need for review of the treatment as well as targeted screening and management of SIB in heroin users attending treatment services.

Analysis of Stimulant Prescriptions and Drug-Related Poisoning Risk Among Persons Receiving Buprenorphine Treatment for Opioid Use Disorder

IMPORTANCE

Stimulant medication use is common among individuals receiving buprenorphine for opioid use disorder (OUD). Associations between prescription stimulant use and treatment outcomes in this population have been understudied.

OBJECTIVES

To investigate whether use of prescription stimulants was associated with (1) drug-related poisoning and (2) buprenorphine treatment retention.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, recurrent-event cohort study with a case-crossover design used a secondary analysis of administrative claims data from IBM MarketScan Commercial and Multi-State Medicaid databases from January 1, 2006, to December 31, 2016. Primary analyses were conducted from March 1 through August 31, 2021. Individuals aged 12 to 64 years with an OUD diagnosis and prescribed buprenorphine who experienced at least 1 drug-related poisoning were included in the analysis. Unit of observation was the person-day.

EXPOSURES

Days of active stimulant prescriptions.

MAIN OUTCOMES AND MEASURES

Primary outcomes were drug-related poisoning and buprenorphine treatment retention. Drug-related poisonings were defined using International Classification of Diseases, Ninth Revision, and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, codes; treatment retention was defined by continuous treatment claims until a 45-day gap was observed.

RESULTS

There were 13 778 567 person-days of observation time among 22 946 individuals (mean [SD] age, 32.8 [11.8] years; 50.3% men) who experienced a drug-related poisoning. Stimulant treatment days were associated with 19% increased odds of drug-related poisoning (odds ratio [OR], 1.19 [95% CI, 1.06-1.34]) compared with nontreatment days; buprenorphine treatment days were associated with 38% decreased odds of poisoning (OR, 0.62 [95% CI, 0.59-0.65]). There were no significant interaction effects between use of stimulants and buprenorphine. Stimulant treatment days were associated with decreased odds of attrition from buprenorphine treatment (OR, 0.64 [95% CI, 0.59-0.70]), indicating that stimulants were associated with 36% longer mean exposure to buprenorphine and its concomitant protection.

CONCLUSIONS AND RELEVANCE

Among persons with OUD, use of prescription stimulants was associated with a modest increase in per-day risk of drug-related poisoning, but this risk was offset by the association between stimulant use and improved retention to buprenorphine treatment, which is associated with protection against overdose.

Undetected Respiratory Depression in People with Opioid Use Disorder

BACKGROUND

Opioid-related deaths are increasing globally. Respiratory complications of opioid use and underlying respiratory disease in people with Opioid Use Disorder (OUD) are potential contributory factors. Individual variation in susceptibility to overdose is, however, incompletely understood. This study investigated the prevalence of respiratory depression (RD) in OUD treatment and compared this to patients with chronic obstructive pulmonary disease (COPD) of equivalent severity. We also explored the contribution of opioid agonist treatment (OAT) dosage, and type, to the prevalence of RD.

METHODS

There were four groups of participants: 1) OUD plus COPD ('OUD-COPD', n = 13); 2) OUD without COPD ('OUD', n = 7); 3) opioid-naïve COPD patients ('COPD'n = 13); 4) healthy controls ('HC'n = 7). Physiological indices, including pulse oximetry (SpO₂%), end-tidal CO₂ (ETCO₂), transcutaneous CO₂ (TcCO₂), respiratory airflow and second intercostal space parasternal muscle electromyography (EMG_para), were recorded continuously over 40 min whilst awake at rest. Significant RD was defined as: SpO₂%< 90% for > 10 s, ETCO₂ per breath > 6.6 kPa, TcCO₂ overall mean > 6 kPa, respiratory pauses > 10 s RESULTS: At least one indicator was observed in every participant with OUD (n = 20). This compared to RD episode occurrence in only 2/7 HC and 2/13 COPD participants (p < 0.05,Fisher's exact test). The occurrence of RD was similar in OUD participants prescribed methadone (n = 6) compared to those prescribed buprenorphine (n = 12).

CONCLUSIONS

Undetected RD is common in OUD cohorts receiving OAT and is significantly more severe than in opioid-naïve controls. RD can be assessed using simple objective measures. Further studies are required to determine the association between RD and overdose risk.

Causes of death among people who used illicit opioids in England, 2001-18: a matched cohort study

BACKGROUND

In many countries, the average age of people who use illicit opioids, such as heroin, is increasing. This has been suggested to be a reason for increasing numbers of opioid-related deaths seen in surveillance data. We aimed to describe causes of death among people who use illicit opioids in England, how causes of death have changed over time, and how they change with age.

METHODS

In this matched cohort study, we studied patients in the Clinical Practice Research Datalink with recorded illicit opioid use (defined as aged 18-64 years, with prescriptions or clinical observations that indicate use of illicit opioids) in England between Jan 1, 2001, and Oct 30, 2018. We also included a comparison group, matched (1:3) for age, sex, and general practice with no records of illicit opioid use before cohort entry. Dates and causes of death were obtained from the UK Office for National Statistics. The cohort exit date was the earliest of date of death or Oct 30, 2018. We described rates of death and calculated cause-specific standardised mortality ratios. We used Poisson regression to estimate associations between age, calendar year, and cause-specific death.

FINDINGS

We collected data for 106 789 participants with a history of illicit opioid use, with a median follow-up of 8·7 years (IQR 4·3-13·5), and 320 367 matched controls with a median follow-up of 9·5 years (5·0-14·4). 13 209 (12·4%) of 106 789 participants in the exposed cohort had died, with a standardised mortality ratio of 7·72 (95% CI 7·47-7·97). The most common causes of death were drug poisoning (4375 [33·1%] of 13 209), liver disease (1272 [9·6%]), chronic obstructive pulmonary disease (COPD; 681 [5·2%]), and suicide (645 [4·9%]). Participants with a history of illicit opioid use had higher mortality rates than the comparison group for all causes of death analysed, with highest standardised mortality ratios being seen for viral hepatitis (103·5 [95% CI 61·7-242·6]), HIV (16·7 [9·5-34·9]), and COPD (14·8 [12·6-17·6]). In the exposed cohort, at age 20 years, the rate of fatal drug poisonings was 271 (95% CI 230-313) per 100 000 person-years, accounting for 59·9% of deaths at this age, whereas the mortality rate due to non-communicable diseases was 31 (16-45) per 100 000 person-years, accounting for 6·8% of deaths at this age. Deaths due to non-communicable diseases increased more rapidly with age (1155 [95% CI 880-1431] deaths per 100 000 person-years at age 50 years; accounting for 52·0% of deaths at this age) than did deaths due to drug poisoning (507 (95% CI 452-562) per 100 000 person-years at age 50 years; accounting for 22·8% of deaths at this age). Mirroring national surveillance data, the rate of fatal drug poisonings in the exposed cohort increased from 345 (95% CI 299-391) deaths per 100 000 person-years in 2010-12 to 534 (468-600) per 100 000 person-years in 2016-18; an increase of 55%, a trend that was not explained by ageing of participants.

INTERPRETATION

People who use illicit opioids have excess risk of death across all major causes of death we analysed. Our findings suggest that population ageing is unlikely to explain the increasing number of fatal drug poisonings seen in surveillance data, but is associated with many more deaths due to non-communicable diseases.

FUNDING

National Institute for Health Research.

Why are drug-related deaths among women increasing in Scotland? A mixed-methods analysis of possible explanations

Drug-related deaths have increased significantly in Scotland in recent years, with a much greater percentage increase in deaths among women than among men. We undertook a mixed-methods project to identify explanations for this trend, comprising three parallel methodological strands: (i) an analysis of available routine data, including drug treatment data, death registrations, and surveys of people using needle exchanges; (ii) thematic analysis of interviews and focus groups with professional stakeholders and (iii) secondary analysis of interviews with women who use drugs. Results indicated that the observed trend is likely to reflect multiple, interacting causes. Potential contributors identified were: ageing; changing patterns of substance use; increasing prevalence of physical and mental health co-morbidities; changing relationships and parenting roles; changes to treatment services and wider health and social care provision; unintended consequences or poor implementation of recovery-oriented practice; and changes in the social security system. Policy responses to rising drug-related death rates require a gender-informed approach, recognising the commonalities and differences between men and women who use drugs; the diversity of experiences within each gender; and the intersections between gender and other forms of inequality, such as poverty.

Increasing drug-related mortality rates over the last decade in Scotland are not just due to an ageing cohort: A retrospective longitudinal cohort study

BACKGROUND

In Europe, North America, and Australia, mortality due to drug-related (DR) causes amongst people who inject drugs (PWID) is a major issue. Our objective was to characterise temporal trends in DR mortality rates in a large cohort of PWID in Scotland over the past decade, all of whom had been diagnosed with hepatitis C virus (HCV) infection, and to investigate factors associated with DR mortality.

METHODS

Retrospective longitudinal cohort study linking Scotland's national HCV Diagnosis Database and deaths registry. The study cohort consisted of all individuals with likely injection drug use-related route of HCV acquisition, who had been diagnosed with HCV between 1991 and 2018, and were alive and aged under 65 years on 1 January 2009. We used Lexis expansion to adjust for ageing cohort effects and calculated the mortality rate from an underlying/contributing DR cause over the period 2009-2018. We fitted Poisson regression models to estimate the temporal trend adjusting for attained age, sex, referral setting, region, and viraemic status at baseline.

RESULTS

Amongst the study population (n = 35,065; 236,914 person-years), a total of 1900 DR deaths occurred; the DR mortality rate increased from 5.6/1000 [101 deaths] in 2009 to 12.4/1000 [342] person-years in 2018. Increasing trends were observed for all age-groups except 55-64 years. The overall DR mortality rate was highest for referrals for HCV testing from prison (11.0/1000) and hospital settings (10.0/1000). Mortality increased with calendar time period, with significantly raised adjusted rate ratios (RRs) from 2015 (RR=1.40, 95% CI:1.16-1.69) to 2018 (RR=2.23, 95% CI:1.88-2.64), compared with 2011-2012, for older age (35-44: RR=1.37, 95% CI:1.20-1.56; 45-54: RR=1.32, CI:1.14-1.53) compared with <35 years, for persons diagnosed with HCV since 2009 (RR=1.34, 95% CI:1.21-1.49), and for prison and hospital referrals (RRs of 1.30, 1.37) compared with GP referrals.

CONCLUSION

Increasing DR mortality rates in Scotland over the past decade are not just due to an ageing cohort. Harm reduction services will likely need to expand and adapt to reverse the recent upward trends in DR mortality in PWID.

Musculoskeletal Disorders, Pain Medication, and in-Hospital Mortality among Patients with COVID-19 in South Korea: A Population-Based Cohort Study

We aimed to investigate whether comorbid musculoskeletal disorders (MSD)s and pain medication use was associated with in-hospital mortality among patients with coronavirus disease 2019 (COVID-19). Adult patients (≥20 years old) with a positive COVID-19 diagnosis until 5 June 2020 were included in this study, based on the National Health Insurance COVID-19 database in South Korea. MSDs included osteoarthritis, neck pain, lower back pain, rheumatoid arthritis, and others, while pain medication included paracetamol, gabapentin, pregabalin, glucocorticoid, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids (strong and weak opioids), and benzodiazepine. Primary endpoint was in-hospital mortality. A total of 7713 patients with COVID-19 were included, and in-hospital mortality was observed in 248 (3.2%) patients. In multivariate logistic regression analysis, no MSDs (p > 0.05) were significantly associated with in-hospital mortality. However, in-hospital mortality was 12.73 times higher in users of strong opioids (odds ratio: 12.73, 95% confidence interval: 2.44–16.64; p = 0.002), while use of paracetamol (p = 0.973), gabapentin or pregabalin (p = 0.424), glucocorticoid (p = 0.673), NSAIDs (p = 0.979), weak opioids (p = 0.876), and benzodiazepine (p = 0.324) was not associated with in-hospital mortality. In South Korea, underlying MSDs were not associated with increased in-hospital mortality among patients with COVID-19. However, use of strong opioids was significantly associated with increased in-hospital mortality among the patients.

Big data and predictive modelling for the opioid crisis: existing research and future potential

A need exists to accurately estimate overdose risk and improve understanding of how to deliver treatments and interventions in people with opioid use disorder in a way that reduces such risk. We consider opportunities for predictive analytics and routinely collected administrative data to evaluate how overdose could be reduced among people with opioid use disorder. Specifically, we summarise global trends in opioid use and overdoses; describe the use of big data in research into opioid overdose; consider the potential for predictive modelling, including machine learning, for prevention and monitoring of opioid overdoses; and outline the challenges and risks relating to the use of big data and machine learning in reducing harms that are related to opioid use. Future research for improving the coverage and provision of existing interventions, treatments, and resources for opioid use disorder requires collaboration of multiple agencies. Predictive modelling could transport the concept of stratified medicine to public health through novel methods, such as predictive modelling and emulated trials for evaluating diagnoses and prognoses of opioid use disorder, predicting treatment response, and providing targeted treatment recommendations.

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.

Prevalence and correlates of multiple non-fatal opioid overdoses among people who inject drugs who utilise needle syringe programs in Australia

BACKGROUND

Non-fatal overdose (NFOD) is a major cause of morbidity among people who inject drugs (PWID) and multiple NFOD is associated with increased risk of fatal overdose. Despite this, few studies have examined the prevalence and correlates of drug-specific multiple NFOD. The current study aimed to determine the prevalence and correlates of recent multiple non-fatal opioid overdose (NFOOD) among PWID who access needle syringe programs (NSPs) in Australia.

METHODS

The Australian Needle and Syringe Program Survey is conducted annually and was conducted at 46 sites across Australia in 2019. Participation involves completion of a self-administered questionnaire and a capillary dried blood spot for HIV and hepatitis C virus testing. In 2019, respondents who reported a minimum of one NFOOD in the previous 12 months (recent NFOOD) were asked to complete supplementary questions regarding their last NFOOD. Bivariate and multivariate logistic regression were used to determine factors independently associated with multiple recent NFOOD.

RESULTS

A total of 222 respondents reported recent NFOOD. Respondents were predominantly male (59%), one third (39%) were aged less than 39 years and 73% reported last injecting heroin at their last NFOOD. One in two respondents (48%, n = 107) reported multiple opioid overdoses (median 3, interquartile range 2-5). The odds of reporting multiple NFOOD were higher among respondents who reported injecting in a public location at their last NFOOD (adjusted odds ratio [AOR] 2.10, 95% CI 1.14-3.90, p = 0.018) and benzodiazepine use in the 12 h prior to NFOOD (AOR 2.74, 95% CI 1.50-4.99, p = 0.001).

CONCLUSIONS

Multiple NFOOD was prevalent among PWID who utilised NSPs who reported recent NFOOD. Public injecting and benzodiazepine use were associated with increased risk of multiple NFOOD, and there is a need for interventions specifically targeting PWID who report these high risk injecting practices.

Scotland's 2009-2015 methadone-prescription cohort: Quintiles for daily dose of prescribed methadone and risk of methadone-specific death

AIMS

As methadone clients age, their drug-related death (DRD) risks increase, more than doubling at 45+ years for methadone-specific DRDs.

METHODS

Using Community Health Index (CHI) numbers, mortality to 31 December 2015 was ascertained for 36 347 methadone-prescription clients in Scotland during 2009-2015. Cohort entry, quantity of prescribed methadone and daily dose (actual or recovered by effective, simple rules) were defined by clients' first CHI-identified methadone prescription after 30 June 2009 and used in proportional hazards analysis. As custodian of death records, National Records of Scotland identified non-DRDs from DRDs. Methadone-specific DRD means methadone was implicated but neither heroin nor buprenorphine.

RESULTS

The cohort's 192 928 person-years included 1857 non-DRDs and 1323 DRDs (42%), 546 of which were methadone specific. Actual/recovered daily dose was available for 26 533 (73%) clients who experienced 420 methadone-specific DRDs. Top quintile for daily dose at first CHI-identified methadone prescription was >90 mg. Age 45+ years at cohort-entry (hazard ratio vs 25-34 years: 3.1, 95% confidence interval: 2.4-4.2), top quintile for baseline daily dose of prescribed methadone (vs 50-70 mg: 1.9, 1.1-3.1) and being female (1.3, 1.0-1.6) significantly increased clients' risk of methadone-specific DRD.

CONCLUSION

Extra care is needed when methadone daily dose exceeds 90 mg. Females' higher risk for methadone-specific DRD is new and needs validation. Further analyses of prescribed daily dose linked to mortality for large cohorts of methadone clients are needed internationally, together with greater pharmacodynamic and pharmacokinetic understanding of methadone by age and sex. Balancing age-related risks is challenging for prescribers who manage chronic opiate dependency against additional uncertainty about the nature, strength and pharmacological characteristics of drugs from illegal markets.

Tobacco Smoking Rates in a National Cohort of People with Substance Use Disorder Receiving Treatment

BACKGROUND AND AIM

The prevalence of tobacco smoking among individuals receiving treatment for substance use disorder (SUD) remains high. Respiratory disease and other harms are of prime concern to health policy-makers, given the contributory role played by tobacco smoking in the excess rates of premature mortality seen in individuals with SUD. The aim was to use SUD treatment data to investigate tobacco smoking prevalence among subgroups of adults over the course of treatment.

METHODS

We used the English National Drug Treatment Monitoring System (NDTMS) to examine number of days tobacco had been smoked in the previous month in adults receiving SUD treatment (N = 106,472, median length of treatment 157 days).

RESULTS

At baseline (treatment start), 48.7% reported smoking tobacco; the highest rate was observed in opiate users (61%). Overall, the level of smoking at the latest assessment was 48.5%. Reductions (of between 5 and 7%) were observed among those who finished treatment but only within the final stages of treatment. A 5% increase in smoking was observed in those still in treatment within the study timeframe.

CONCLUSIONS

This study identifies the potential for a greater emphasis on reducing tobacco consumption within SUD treatment, for example, by offering all smokers within SUD treatment smoking cessation support as part of their SUD treatment programme.

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.

Opioid agonist treatment and fatal overdose risk in a state-wide US population receiving opioid use disorder services

BACKGROUND AND AIMS

Evidence from randomized controlled trials establishes that medication treatment with methadone and buprenorphine reduces opioid use and improves treatment retention. However, little is known about the role of such medications compared with non-medication treatments in mitigating overdose risk among US patient populations receiving treatment in usual care settings. This study compared overdose mortality among those in medication versus non-medication treatments in specialty care settings.

DESIGN

Retrospective cohort study using state-wide treatment data linked to death records. Survival analysis was used to analyze data in a time-to-event framework.

SETTING

Services delivered by 757 providers in publicly funded out-patient specialty treatment programs in Maryland, USA between 1 January 2015 and 31 December 2016.

PARTICIPANTS

A total of 48 274 adults admitted to out-patient specialty treatment programs in 2015-16 for primary diagnosis of opioid use disorder.

MEASUREMENTS

Main exposure was time in medication treatment (methadone/buprenorphine), time following medication treatment, time exposed to non-medication treatments and time following non-medication treatment. Main outcome was opioid overdose death during and after treatment. Hazard ratios were calculated using Cox proportional hazard regression. Propensity score weights were adjusted for patient information on sex, age, race, region of residence, marital and veteran status, employment, homelessness, primary opioid, mental health treatment, arrests and criminal justice referral.

FINDINGS

The study population experienced 371 opioid overdose deaths. Periods in medication treatment were associated with substantially reduced hazard of opioid overdose death compared with periods in non-medication treatment [adjusted hazard ratio (aHR) = 0.18, 95% confidence interval (CI) = 0.08-0.40]. Periods after discharge from non-medication treatment (aHR = 5.45, 95% CI = 2.80-9.53) and medication treatment (aHR = 5.85, 95% CI = 3.10-11.02) had similar and substantially elevated risks compared with periods in non-medication treatments.

CONCLUSIONS

Among Maryland patients in specialty opioid treatment, periods in treatment are protective against overdose compared with periods out of care. Methadone and buprenorphine are associated with significantly lower overdose death compared with non-medication treatments during care but not after treatment is discontinued.

Cost-effectiveness of the HepCATT intervention in specialist drug clinics to improve case-finding and engagement with HCV treatment for people who inject drugs in England

BACKGROUND AND AIMS

People who inject drugs (PWID) are at high risk of hepatitis C virus (HCV) infection; however, ~50% are undiagnosed in England and linkage-to-care is poor. This study investigated the cost-effectiveness of an intervention (HepCATT) to improve case-finding and referral to HCV treatment compared with standard-of-care pathways in drug treatment centres in England.

DESIGN

HCV transmission and disease progression model with cost-effectiveness analysis using a health-care perspective. Primary outcome and cost data from the HepCATT study parameterized the intervention, suggesting that HepCATT increased HCV testing in drug treatment centres 2.5-fold and engagement onto the HCV treatment pathway 10-fold. A model was used to estimate the decrease in HCV infections and HCV-related deaths from 2016, with costs and health benefits (quality-adjusted life-years or QALYs) tracked over 50 years. Univariable and probabilistic sensitivity analyses (PSA) were undertaken.

SETTING

England-specific epidemic with 40% prevalence of chronic HCV among PWID.

PARTICIPANTS

PWID attending drug treatment centres.

INTERVENTION

Nurse facilitator in drug treatment centres to improve the HCV care pathway from HCV case-finding to referral and linkage to specialist care. Comparator was the standard-of-care HCV care pathway.

MEASUREMENTS

Incremental cost-effectiveness ratio (ICER) in terms of cost per QALY gained through improved case-finding.

FINDINGS

Over 50 years per 1000 PWID, the HepCATT intervention could prevent 75 (95% central interval 37-129) deaths and 1330 (827-2040) or 51% (30-67%) of all new infections. The mean ICER was £7986 per QALY gained, with all PSA simulations being cost-effective at a £20 000 per QALY willingness-to-pay threshold. Univariable sensitivity analyses suggest the intervention would become cost-saving if the cost of HCV treatment reduces to £3900. If scaled up to all PWID in England, the intervention would cost £8.8 million and decrease incidence by 56% (33-70%) by 2030.

CONCLUSIONS

Increasing hepatitis C virus infection case-finding and treatment referral in drug treatment centres could be a highly cost-effective strategy for decreasing hepatitis C virus incidence among people who inject drugs.

Prevalence of respiratory conditions among people who use illicit opioids: a systematic review

BACKGROUND AND AIMS

There are growing concerns over the respiratory health of people who use illicit opioids due to high rates of opioid inhalation and tobacco smoking in this group. This study aimed to summarize the evidence relating illicit opioid use with poor respiratory health.

METHODS

A systematic review of the literature on the association between illicit opioid use and respiratory health was undertaken in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance (PROSPERO ID = CRD42017059953). Electronic searches of MEDLINE, Embase, PsycINFO, CINAHL and the Cochrane Library databases were undertaken (English language, published January 1980-November 2018). All study designs excluding case studies were considered. Studies were undertaken in community and hospital settings in the United States (n = 23), United Kingdom (n = 7), Australia (n = 7), the Netherlands (n = 2), Canada (n = 2), Ireland (n = 1), Spain (n = 1) and Iran (n = 1). Measurements of respiratory disease, including asthma and chronic obstructive pulmonary disease (COPD) and related symptoms were extracted. Data on respiratory-related deaths and hospital admissions were also extracted. Meta-analysis of prevalence data was undertaken using a random effects meta-analysis model with parameters estimated using Markov chain Monte Carlo simulation.

RESULTS

Meta-analyses estimated prevalence of asthma in people who inject illicit opioids as 8.5% [95% predictive interval (PrI) = 0.2%, 74.0%] and as 20.2% (95% PrI = 4.2%, 59.2%) in people who inhale illicit opioids. Prevalence of COPD in people who inject illicit opioids was estimated as 2.7% (95% PrI = 0.0%, 50.4%) and as 17.9% (95% PrI = 0.6%, 89.5%) in people who inhale illicit opioids. There was evidence of moderate to extreme heterogeneity across studies.

CONCLUSIONS

There is evidence of increased burden of respiratory diseases in people who use illicit opioids. Due to the heterogeneity of study design and samples, it is difficult to gain accurate estimates of the prevalence of respiratory disease in this population.

The epidemiology of regular opioid use and its association with mortality: Prospective cohort study of 466 486 UK biobank participants

BACKGROUND

Opioids have, at most, small benefits for non-cancer pain in the medium and long-term but there is good evidence that they cause harm. The current study describes the characteristics and clinical status of people taking regular opioids in Great Britain and determines whether use is associated with mortality risk.

METHODS

An analysis of participants in UK Biobank, a prospective population-based study. At recruitment (2006-10) participants reported medicines which they regularly used in addition to lifestyle and health-related factors. Information was available on deaths until October 2016.

FINDINGS

There were 466 486 participants (54% women) aged 40-69 years and without a prior history of cancer of whom 5.5% were regularly using opioids. Use increased with age-group, was more common in females (6.3% v. 4.6%) and 87% of persons using them reported chronic pain. The highest rates of use (~1 in 9) were in people with low household income, who left school <16 years and lived in areas with high deprivation. Amongst 15,032 people who could not work because of ill-health, 1 in 3 were regularly taking opioids. Regular users reported insomnia (88.7%), a recent major recent life event (57.3%) and were much more likely than non-users to rate their health as poor (RR 5.5, 99% CI (4.9, 6.1)). Those taking weak (4.2% of participants) or strong (1.4%) opioids were more likely to die during follow-up (6.9% and 9.1% respectively v. 3.3% in non-users) an excess which remained after adjustment for demographic, socio-economic, health and lifestyle factors (MRR 1.18 99% CI (1.06, 1.32) and 1.20 99% CI (1.01, 1.43)) respectively.

INTERPRETATION

Regular use of opioids is common in Great Britain, particularly in groups of low socio-economic status. Most users still report chronic pain, poor health generally and are at increased risk of premature death although it is not established that this relationship is causal.

FUNDING

There were no external sources of funding obtained for the current analyses.

Metabolic and Addiction Indices in Patients on Opioid Agonist Medication-Assisted Treatment: A Comparison of Buprenorphine and Methadone

Metabolic hormones stabilize brain reward and motivational circuits, whereas excessive opioid consumption counteracts this effect and may impair metabolic function. Here we addressed the role of metabolic processes in the course of the agonist medication-assisted treatment for opioid use disorder (OUD) with buprenorphine or methadone. Plasma lipids, hemoglobin A1C, body composition, the oral glucose tolerance test (oGTT) and the Sweet Taste Test (STT) were measured in buprenorphine- (n = 26) or methadone (n = 32)- treated subjects with OUD. On the whole, the subjects in both groups were overweight or obese and insulin resistant; they displayed similar oGTT and STT performance. As compared to methadone-treated subjects, those on buprenorphine had significantly lower rates of metabolic syndrome (MetS) along with better values of the high-density lipoproteins (HDL). Subjects with- vs. without MetS tended to have greater addiction severity. Correlative analyses revealed that more buprenorphine exposure duration was associated with better HDL and opioid craving values. In contrast, more methadone exposure duration was associated with worse triglycerides-, HDL-, blood pressure-, fasting glucose- and hemoglobin A1C values. Buprenorphine appears to produce beneficial HDL- and craving effects and, contrary to methadone, its role in the metabolic derangements is not obvious. Our data call for further research aimed at understanding the distinctive features of buprenorphine metabolic effects vis-à-vis those of methadone and their potential role in these drugs' unique therapeutic profiles.

Correlates of death during outpatient treatment for opioid use disorder: A national study

BACKGROUND

As the burden of opioid use disorder (OUD) increases in the United States, manifold federal and state initiatives have sought to increase access to treatment for OUD, which includes behavioral and pharmaceutical treatment modalities. Although the evidence base for outpatient treatment for OUD-including medications for opioid use disorder-is substantial, few studies have examined the risk factors for fatality during treatment for OUD.

METHODS

Treatment Episode Data Set-Discharges (TEDS-D) data were used to evaluate correlates of death during outpatient treatment for OUD in 2016. To determine the correlates of mortality during an outpatient treatment for OUD, we constructed a pooled logistic regression model, stratified by use of medication for opioid use disorder (MOUD), to control for the duration of time in treatment and to identify the independent characteristics that may lead to differences in the odds of mortality during treatment.

FINDINGS

1861 (0.8%) of 235,745 outpatient treatment episodes for OUD included in our analysis resulted in fatality. Many factors correlated with death during treatment were similar for individuals who did and did not receive MOUD. However, non-White race was only significantly associated with decreases in fatality in non-MOUD treatment episodes. Male sex and reported intravenous drug use at admission were associated with fatality only for treatment episodes that did not involve MOUD.

CONCLUSIONS

In this national study of outpatient treatment episodes for OUD, we found differences in age, sex, region, drug use history, treatment setting, and treatment history significantly affected the risk of death during treatment. As more people become engaged with treatment, facilities should work toward delivering optimal treatment for all patients regardless of personal characteristics.

Acute stressors and clinical characteristics differentiate death by suicide, accident, or natural causes among illicit and prescription opiate users

BACKGROUND

Opiate misuse has reached epidemic levels. Prevention efforts depend on distinguishing opiate users from abusers. The current study compared opioid users who died by natural cases, accidents, and suicide using psychological autopsy methods. Groups were compared on substance use characteristics, treatment history, experiences of negative life events, and circumstances at the time of death.

METHODS

Substance use and suicide risk were evaluated using psychological autopsy methods in 63 decedents with positive toxicology for opiates at death divided into three groups: adults dying by suicide (n = 19), accident (n = 19), and natural causes (n = 25). Groups were compared on several dependent measures, using chi-square analyses to examine categorical variables and one-way analyses of variance (ANOVA) to examine continuous variables.

RESULTS

Individuals who died by suicide were similar in many ways to adults who died by an accidental overdose. However, suicide completers were more likely to have struggled with severe depression, and previously attempted suicide, whereas the accidental overdose sample was more likely to display a chronic pattern of severe drug abuse.

CONCLUSIONS

The current study helps to distinguish between opiate users who are at risk for death by an accidental or intentional overdose. In the ongoing opiate crisis, clinicians must understand the risk of overdose and the nuances of accidental behaviors compared to purposeful ones. Signs of suicidal planning, relevant psychopathology, and ongoing life stress may be useful points of intervention for stopping the increasing number of deaths among opiate users.

COPD and asthma in patients with opioid dependency: a cross-sectional study in primary care

Patients treated for drug addiction have high asthma and COPD prevalence rates. The relative contributions of cigarette smoking, smoking intensity and possible smoking of other substances has not been described. We aimed to describe the prevalence and determinants of asthma and COPD in patients prescribed methadone as opioid substitution therapy (OST). In a cross-sectional study of an anonymised patient-level primary care dataset of UK inner-city general practices (n = 46), 321,395 patients aged ≥18 years were identified. A total of 676 (0.21%) had a record of a methadone ever issued in primary care. The association between respiratory disease and methadone prescribing was examined using logistic regression. Models were adjusted for potential effects of clustering by practice. A total of 97.3% of patients prescribed methadone were cigarette smokers, either current (81.2%) or ex-smokers (16.1%). The prevalences of asthma and COPD were higher in methadone patients (14.2% and 12.4%, respectively) compared to non-methadone patients (4.4% and 1.1%, respectively). Methadone was an independent determinant of asthma, adjusting for smoking status (OR 3.21; 95% CI: 2.52, 4.10) or for smoking intensity (3.08; 2.27, 4.19), and of COPD, adjusting for smoking status (6.00; 4.61, 7.80) or for smoking intensity (5.80; 4.12, 8.17). COPD and asthma prevalence were substantially higher in those prescribed methadone compared to those never prescribed methadone. Prescription of methadone was an independent predictor for both COPD and asthma, even after adjustment for smoking status and smoking intensity. Possible explanations include confounding by association with smoking of heroin or crack cocaine, both of which may have a causal association with COPD and asthma.

Opioid use disorder

Opioid use disorder (OUD) is a chronic relapsing disorder that, whilst initially driven by activation of brain reward neurocircuits, increasingly engages anti-reward neurocircuits that drive adverse emotional states and relapse. However, successful recovery is possible with appropriate treatment, although with a persisting propensity to relapse. The individual and public health burdens of OUD are immense; 26.8 million people were estimated to be living with OUD globally in 2016, with >100,000 opioid overdose deaths annually, including >47,000 in the USA in 2017. Well-conducted trials have demonstrated that long-term opioid agonist therapy with methadone and buprenorphine have great efficacy for OUD treatment and can save lives. New forms of the opioid receptor antagonist naltrexone are also being studied. Some frequently used approaches have less scientifically robust evidence but are nevertheless considered important, including community preventive strategies, harm reduction interventions to reduce adverse sequelae from ongoing use and mutual aid groups. Other commonly used approaches, such as detoxification alone, lack scientific evidence. Delivery of effective prevention and treatment responses is often complicated by coexisting comorbidities and inadequate support, as well as by conflicting public and political opinions. Science has a crucial role to play in informing public attitudes and developing fuller evidence to understand OUD and its associated harms, as well as in obtaining the evidence today that will improve the prevention and treatment interventions of tomorrow.

Screening Heroin Smokers Attending Community Drug Clinics for Change in Lung Function: A Cohort Study

Background

Heroin smokers have high rates of COPD, respiratory morbidity, hospital admission, and mortality. We assessed the natural history of symptoms and lung function in this population over time.

Methods

A cohort of heroin smokers with COPD was followed for 18 to 24 months. At baseline and follow-up, respiratory symptoms were measured by the Medical Research Council Dyspnea Scale (MRC) and the COPD Assessment Tool (CAT), and postbronchodilator spirometry was performed. Frequency of health-care-seeking episodes was extracted from routine health records. Parametric, nonparametric, and linear regression models were used to analyze the change in symptoms and lung function over time.

Results

Of 372 participants originally recruited, 161 were assessed at follow-up (mean age, 51.0 ± 5.3 years; 74 women [46%]) and 106 participants completed postbronchodilator spirometry. All participants were current or previous heroin smokers, and 122 (75.8%) had smoked crack. Symptoms increased over time (MRC score increased by 0.48 points per year, P < .001; CAT score increased by 1.60 points per year, P < .001). FEV₁ declined annually by 90 ± 190 mL (P < .001). This deterioration was not associated with change in tobacco or heroin smoking status or use of inhaled medications.

Conclusions

Heroin smokers experience a high and increasing burden of chronic respiratory symptoms and a decline in FEV₁ that exceeds the normal age-related decline observed among tobacco smokers with COPD and healthy nonsmokers. Targeted COPD diagnostic and treatment services hosted within opiate substitution services could benefit this vulnerable, relatively inaccessible, and underserved group of people.

Causes of hospital admission and mortality among 6683 people who use heroin: A cohort study comparing relative and absolute risks

BACKGROUND

Mortality in high-risk groups such as people who use illicit drugs is often expressed in relative terms such as standardised ratios. These measures are highest for diseases that are rare in the general population, such as hepatitis C, and may understate the importance of common long-term conditions.

POPULATION

6683 people in community-based treatment for heroin dependence between 2006 and 2017 in London, England, linked to national hospital and mortality databases with 55,683 years of follow-up.

METHOD

Age- and sex-specific mortality and hospital admission rates in the general population of London were used to calculate the number of expected events. We compared standardised ratios (relative risk) to excess deaths and admissions (absolute risk) across ICD-10 chapters and subcategories.

RESULTS

Drug-related diseases had the highest relative risks, with a standardised mortality ratio (SMR) of 48 (95% CI 42-54) and standardised admission ratio (SAR) of 293 (95% CI 282-304). By contrast, other diseases had an SMR of 4.4 (95% CI 4.0-4.9) and an SAR of 3.15 (95% CI 3.11-3.19). However, the majority of the 621 excess deaths (95% CI 569-676) were not drug-related (361; 58%). The largest groups were liver disease (75 excess deaths) and COPD (45). Similarly, 80% (11,790) of the 14,668 excess admissions (95% CI 14,382-14,957) were not drug-related. The largest groups were skin infections (1073 excess admissions), alcohol (1060), COPD (812) and head injury (612).

CONCLUSIONS

Although relative risks of drug-related diseases are very high, most excess morbidity and mortality in this cohort was caused by common long-term conditions.

Prevalence and correlates of suicide attempt among Chinese individuals receiving methadone maintenance treatment for heroin dependence

To date, there have been very limited studies regarding the clinical epidemiology of attempted suicide in Chinese individuals with heroin-dependence. The objective of this study was to examine the prevalence and correlates of suicide attempt in Chinese individuals receiving methadone maintenance treatment for heroin dependence. Demographic, clinical, and psychosocial data of 603 methadone-maintained patients with heroin dependence were collected with a standardized self-administered questionnaire. The presence of suicide attempt and antisocial personality disorder was assessed by using a single question and the Mini-International Neuropsychiatric Interview 5.0. The one-month and lifetime prevalence rates of suicide attempt were 9.5% and 34.2%, respectively. In multivariable logistic regression, lifetime suicide attempt was significantly associated with female gender (OR = 2.81), being 20–39 years old (OR = 2.73), an education level of primary school or lower (OR = 2.07), poor economic status (OR = 3.06), injecting heroin before methadone maintenance treatment (OR = 2.92), depressive symptoms (OR = 3.46), anxiety symptoms (OR = 1.88), and antisocial personality disorder (OR = 2.85). Suicide attempt is very prevalent among Chinese individuals receiving methadone maintenance treatment for heroin dependence. Services for patients with heroin dependence in methadone maintenance treatment clinics in China should include psychosocial supports, periodic screening for suicide attempt and other suicidal behaviors and, when needed, psychiatric treatment and crisis intervention.

Non drug-related and opioid-specific causes of 3262 deaths in Scotland's methadone-prescription clients, 2009-2015

BACKGROUND

Opioid drug use is a major cause of premature mortality, with opioid substitution therapy the leading intervention. As methadone-clients age, non-drug-related deaths (non-DRDs) predominate and DRD-risks increase differentially, quadrupling at 45+ years for methadone-specific DRDs.

METHODS

36,606 methadone-prescription-clients in Scotland during 2009-2015 were linked to mortality records to end-2015 by their Community Health Index (CHI). Cohort-entry, also baseline quantity of prescribed methadone, were defined by clients' first CHI-identified methadone-prescription during 2009-2015. National Records of Scotland identified non-DRDs from DRDs; and provided ICD10 codes for underlying and co-present causes of death. Methadone-specific DRD means methadone was implicated in DRD but neither heroin nor buprenorphine.

RESULTS

During 193,800 person-years of follow-up, 1939 non-DRDs (59%) and 1323 DRDs occurred, of which 546 were methadone-specific. Predominant underlying ICD10 chapters for non-DRDs were: neoplasm (377); external causes (341); diseases of digestive (303), circulatory (286) or respiratory (212) system. As methadone-clients aged, the non-DRD proportion of their deaths increased from 54% (717/1318) at 35-44 years to 89% (372/417) at 55+ years. After allowing for DRDs' opioid-specificity, age-group and quintile for last-prescribed methadone, there was a significant, positive interaction for co-present circulatory disease between top-quintile for prescribed methadone and 45+ years at death (p = 0.033 after Bonferroni); not for digestive or respiratory co-presence.

CONCLUSIONS

Circulatory disease is the co-morbidity most likely implicated in the quadrupling of methadone-specific DRD-risk at 45+ years; followed by digestive disease. Cultural shift is needed in treatment-services because degenerative non-DRDs predominate as methadone-clients age. Future linkage-studies should access hospitalizations and methadone-daily-dose.

The impact of opiate substitution treatment on mortality risk in drug addicts: a natural experiment study

Background

Opiate substitution treatment (OST) is the main treatment for people addicted to heroin and other opioid drugs. However, there is limited information on how the delivery of this treatment affects mortality risk.

Objectives

To investigate the associations of mortality risk with periods during treatment and following cessation of treatment, medication type, co-prescription of other medication and dosing regimens during titration and detoxification. The trends with time of prescribed medication, dose and treatment duration were also explored.

Design

Prospective longitudinal observational study.

Setting

UK primary care between 1998 and 2014.

Participants

A total of 12,780 patients receiving methadone, buprenorphine or dihydrocodeine.

Main outcome measures

All-cause mortality relating to 657 deaths and drug-related poisoning relating to 113 deaths.

Data sources

Clinical Practice Research Datalink with linked information on cause of death from the Office for National Statistics.

Results

For both outcomes, the lowest mortality risk was observed after 4 weeks of treatment and the highest risk was observed in the first 4 weeks following cessation of treatment [e.g. for drug-related poisoning, incidence rate ratio (IRR) 8.15, 95% confidence interval (CI) 5.45 to 12.19]. There was evidence that the treatment period risks varied with OST medication. The largest difference in risk was for the first 4 weeks of treatment for both outcomes, with patients on buprenorphine being at lower risk than those on methadone (e.g. for drug-related poisoning, IRR 0.08, 95% CI 0.01 to 0.48). The co-prescription of benzodiazepines was associated with linearly increasing the risk of drug-related deaths by dose (IRR 2.02, 95% CI 1.66 to 2.47), whereas z-drugs (zolpidem, zopiclone and zaleplon) were associated with increased risk of both all-cause (IRR 1.83, 95% CI 1.59 to 2.12) and drug-related (IRR 3.31, 95% CI 2.45 to 4.47) mortality. There was weak evidence that higher initial and final doses were associated with increased all-cause mortality risk. In the first 4 weeks of treatment, the risk increased by 4% for each 5-mg increment in methadone dose (1-mg increase in buprenorphine) (hazard ratio 1.04, 95% CI 1.00 to 1.09). In the first 4 weeks after treatment ceased, a similar increment in final dose increased the risk by 3% (hazard ratio 1.03, 95% CI 0.99 to 1.07). There were too few deaths to evaluate the effects on drug-related poisoning. The proportion of OST patients receiving buprenorphine increased between 1998 and 2006. Median treatment duration was consistently shorter for buprenorphine than for methadone for each year studied (overall median duration of 48 and 106 days, respectively).

Limitations

As this was an observational study, the possibility remains of bias from unmeasured factors, which covariate adjustment and inverse probability weighting can eliminate only partially.

Conclusions

Using buprenorphine as an alternative to methadone may not reduce mortality overall despite resulting in lower IRRs from shorter treatment duration. Clinical guidance needs to consider strengthening warnings about the co-prescription of a range of drugs for OST patients.

Future work

Our analyses need to be replicated using other clinical data sets in the UK and in other countries. New interventions and trials are required to investigate improving the retention of OST patients in primary care.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

Time to look beyond ageing as a factor? Alternative explanations for the continuing rise in drug related deaths in Scotland

Purpose

The purpose of this paper is to examine the reasons and risk factors that explain the threefold increase in drug-related deaths from 267 in 1996 to 934 in 2017 in Scotland. The authors explore the known links between deprivation and problem drug use (PDU) and discuss the impact of drug policy and service provision on PDU and drug-related deaths.

Design/methodology/approach

Using quantitative data sets from the National Records of Scotland (NRS) for drug-related deaths registered in 2017 and data sets from the Scottish Index of Multiple Deprivation (SIMD), we produce statistical data on mortality rates relating to areas of deprivation, gender and age.

Findings

The data highlight the disproportionate number of deaths in the most deprived areas in comparison to the least deprived areas and the national average. Findings indicate that one quarter of male and female DRD in 2017 were under 35. When examining the least deprived vingtile, drug-related deaths account for 2.84 per 100,000 population. Based on this mortality rate calculation, the amount of drug-related deaths are 23 times higher in the most deprived area than the least deprived area.

Research limitations/implications

The research design uses data obtained from the NRS and data from Scottish Multiple Index of Deprivation. Due to the limitations of available data, the research design focused on SIMD population vingtiles.

Practical implications

This research contributes to making unarguable links between entrenched structural inequality and increased drug-related death.

Social implications

This paper contributes to knowledge on the need for drug policy advisors to recognise the importance of deprivation that plays a major part in risks of problematic drug use and harms.

Originality/value

While several national data sets have published information by SIMD vingtile, no published research has sought to investigate the disproportionate number of deaths by population in the most deprived areas.

Screening Heroin Smokers Attending Community Drug Services for COPD

BACKGROUND

Heroin smoking is associated with deprivation, early onset severe emphysema, premature morbidity and mortality, and high use of health care, but individuals engage poorly with traditional health services.

METHODS

In this cross-sectional study, we screened a population of heroin smokers, prescribed opiate substitution therapy by community drug services, for airway disease. We assessed drug exposure, respiratory symptoms, health status, and COPD prevalence. Subjects completed spirometry, completed Medical Research Council (MRC) Dyspnea Scale, COPD Assessment Tool (CAT) questionnaire, recorded drug exposure, and provided feedback.

RESULTS

A total of 753 people (73% of those approached) completed screening, with 260 participants (35%) having COPD using FEV₁/FVC < 0.7 and 293 (39%) participants having COPD using the lower limit of normal. A further 112 participants (15%) had asthma-COPD overlap (ACO) with features of COPD and asthma. Compared with those with normal spirometry, participants with COPD were more breathless (MRC score 3.1 vs 1.9; P < .001) and had worse health status (CAT score 22.9 vs 13.4; P < .001), respectively. Individuals with COPD had smoked cigarettes (P < .001), heroin (P < .001), and crack (P = .03) for longer and were more likely to still be smoking heroin (P < .01). Feedback was strongly positive, with 92% of respondents happy for other health-care appointments to be colocated with drug key worker appointments.

CONCLUSIONS

Most heroin smokers had COPD or ACO, most commonly mild to moderate disease. In high-risk areas, screening this population provides an opportunity to reduce symptoms and risk. Anchoring respiratory health screening to drug center appointments delivers high completion and satisfaction and is an appropriate model for screening other hard-to-reach populations.

Causes of Death After Nonfatal Opioid Overdose

Importance

A recent increase in patients presenting with nonfatal opioid overdoses has focused clinical attention on characterizing their risks of premature mortality.

Objective

To describe all-cause mortality rates, selected cause-specific mortality rates, and standardized mortality rate ratios (SMRs) of adults during their first year after nonfatal opioid overdose.

Design, Setting, and Participants

This US national longitudinal study assesses a cohort of patients aged 18 to 64 years who were Medicaid beneficiaries and experienced nonfatal opioid overdoses. The Medicaid data set included the years 2001 through 2007. Death record information was obtained from the National Death Index. Data analysis occurred from October 2017 to January 2018.

Main Outcomes and Measures

Crude mortality rates per 100 000 person-years were determined in the first year after nonfatal opioid overdose. Standardized mortality rate ratios (SMR) were estimated for all-cause and selected cause-specific mortality standardized to the general population with respect to age, sex, and race/ethnicity.

Results

The primary cohort included 76 325 adults and 66 736 person-years of follow-up. During the first year after nonfatal opioid overdose, there were 5194 deaths, the crude death rate was 778.3 per 10 000 person-years, and the all-cause SMR was 24.2 (95% CI, 23.6-24.9). The most common immediate causes of death were substance use-associated diseases (26.2%), diseases of the circulatory system (13.2%), and cancer (10.3%). For every cause examined, SMRs were significantly elevated, especially with respect to drug use-associated diseases (SMR, 132.1; 95% CI, 125.6-140.0), HIV (SMR, 45.9; 95% CI, 39.5-53.0), chronic respiratory diseases (SMR, 41.1; 95% CI, 36.0-46.8), viral hepatitis (SMR, 30.6; 95% CI, 22.9-40.2), and suicide (SMR, 25.9; 95% CI, 22.6-29.6), particularly including suicide among females (SMR, 47.9; 95% CI, 39.8-52.3).

Conclusions and Relevance

In a US national cohort of adults who had experienced a nonfatal opioid overdose, a marked excess of deaths was attributable to a wide range of substance use-associated, mental health, and medical conditions, underscoring the importance of closely coordinating the substance use, mental health, and medical care of this patient population.

Impact of current and scaled-up levels of hepatitis C prevention and treatment interventions for people who inject drugs in three UK settings-what is required to achieve the WHO's HCV elimination targets?

AIMS

To estimate the impact of existing high-coverage needle and syringe provision (HCNSP, defined as obtaining more than one sterile needle and syringe per injection reported) and opioid substitution therapy (OST) on hepatitis C virus (HCV) transmission among people who inject drugs (PWID) in three UK settings and to determine required scale-up of interventions, including HCV treatment, needed to reach the World Health Organization (WHO) target of reducing HCV incidence by 90% by 2030.

DESIGN

HCV transmission modelling using UK empirical estimates for effect of OST and/or HCNSP on individual risk of HCV acquisition.

SETTING AND PARTICIPANTS

Three UK cities with varying chronic HCV prevalence (Bristol 45%, Dundee 26%, Walsall 19%), OST (72-81%) and HCNSP coverage (28-56%).

MEASUREMENTS

Relative change in new HCV infections throughout 2016-30 if current interventions were stopped. Scale-up of HCNSP, OST and HCV treatment required to achieve the WHO elimination target.

FINDINGS

Removing HCNSP or OST would increase the number of new HCV infections throughout 2016 to 2030 by 23-64 and 92-483%, respectively. Conversely, scaling-up these interventions to 80% coverage could achieve a 29 or 49% reduction in Bristol and Walsall, respectively, whereas Dundee may achieve a 90% decrease in incidence with current levels of intervention because of existing high levels of HCV treatment (47-58 treatments per 1000 PWID). If OST and HCNSP are scaled-up, Walsall and Bristol can achieve the same impact by treating 14 or 40 per 1000 PWID annually, respectively (currently two and nine treatments per 1000 PWID), while 18 and 43 treatments per 1000 PWID would be required if OST and HCNSP are not scaled-up.

CONCLUSIONS

Current opioid substitution therapy and high-coverage needle and syringe provision coverage is averting substantial hepatitis C transmission in the United Kingdom. Maintaining this coverage while getting current drug injectors onto treatment can reduce incidence by 90% by 2030.

Ageing opioid users' increased risk of methadone-specific death in the UK

BACKGROUND

The first evidence that the hazard ratio (HR) for methadone-specific death rises more steeply with age-group than for all drug-related deaths (DRDs) came from Scotland's cohort of 33,000 methadone-prescription clients. We aim to examine, for England, whether illicit opioid users' risk of methadone-specific death increases with age; and to pool age-related HRs for methadone-specific deaths with those for Scotland's methadone-prescription clients.

METHODS

The setting is all services in England that provide publicly-funded, structured treatment for illicit opioid users, the methodology linkage of the English National Drug Treatment Monitoring System and mortality database, and key measurements are DRDs, methadone-specific DRDs, or heroin-specific DRDs, by age-group and gender, with proportional hazards adjustment for substances used, injecting status and periods in/out of treatment.

RESULTS

Linkage was achieved for 129,979 adults receiving prescribing treatment modalities for opioid dependence during April 2005 to March 2009 and followed-up for 378,009 person-years (pys). There were 1,266 DRDs: 271 methadone-specific (7 per 10,000 pys: irrespective of gender) and 473 heroin-specific (15 per 10,000 pys for males, 7 for females). Methadone-specific DRD-rate per 10,000 person-years was 3.5 (95% CI: 2.7-4.4) at 18-34 years, 8.9 (CI: 7.3-10.5) at 35-44 years and 18 (CI: 13.8-21.2) at 45+ years; heroin-specific DRD-rate was unchanged with age. Relative to 25-34 years, pooled HRs for UK clients' methadone-specific deaths were: 0.87 at <25 years (95% CI: 0.56-1.35); 2.14 at 35-44 years (95% CI: 1.76-2.60); 3.75 at 45+ years (95% CI: 2.99-4.70).

CONCLUSION

International testing and explanation are needed of UK's sharp age-related increase in the risk of methadone-specific death. Clients should be alerted that their risk of methadone-specific death increases as they age.

Multiple Systems Estimation (or Capture-Recapture Estimation) to Inform Public Policy

Estimating population sizes has long been of interest, from the estimation of the human or ecological population size within regions or countries to the hidden number of civilian casualties in a war. Total enumeration of the population, for example, via a census, is often infeasible or simply impractical. However, a series of partial enumerations or observations of the population is often possible. This has led to the ideas of capture-recapture methods, which have been extensively used within ecology to estimate the size of wildlife populations, with an associated measure of uncertainty, and are most effectively applied when there are multiple capture occasions. Capture-recapture ideology can be more widely applied to multiple data-sources, by the linkage of individuals across the multiple lists. This is often referred to as Multiple Systems Estimation (MSE). The MSE approach has been preferred when estimating "capture-shy" or hard-to-reach populations, including those caught up in the criminal justice system; or homeless; or trafficked; or civilian casualties of war. Motivated by a range of public policy applications of MSE, each briefly introduced, we discuss practical problems with potentially substantial methodological implications. They include: "period" definition; "case" definition; when an observed count is not a true count of the population of interest but an upper bound due to mismatched definitions; exact or probabilistic matching of "cases" across different lists; demographic or other information about the "case" which may influence capture-propensities; required permissions to access extant-lists; list-creation by research-teams or interested parties; referrals (if presence on list A results - almost surely - in presence on list B); different mathematical models leading to widely different estimated population sizes; uncertainty in estimation; computational efficiency; external validation; hypothesis-generation; and additional independent external information. Returning to our motivational applications, we focus on whether the uncertainty which qualified their estimates was sufficiently narrow to orient public policy; and, if not, what options were available and/or taken to reduce the uncertainty or to seek external validation. We also consider whether MSE was hypothesis-generating: in the sense of having spawned new lines of inquiry.

Effect of initiating drug treatment on the risk of drug-related poisoning death and acquisitive crime among offending heroin users

BACKGROUND

A recent Cochrane review of randomised trials identified a lack of evidence for interventions provided to drug-using offenders. We use routine data to address whether contact with treatment services reduces heroin users' likelihood of a future acquisitive offence or drug-related poisoning (DRP) death.

METHODS

Heroin-users were identified from probation assessments and linked to drug-treatment, mortality and offending records. The study cohort was selected to ensure that the subject was not: in prison, in treatment or had recently left treatment. Subjects were classed as initiators if they attended a triage appointment within two weeks of their assessment; non-initiators otherwise. Initiator and non-initiators were compared over a maximum of one year, with respect to their risk of recorded acquisitive offence or DRP-death. Balance was sought using propensity score matching and missing data were accounted for using multiple imputation.

RESULTS

Nine percent of assessments identified for analysis were classed as initiators. Accounting for observed confounding and missing data, there was a reduction in DRPs associated with initiator assessments, however there was uncertainty around this estimate such that a null-effect could not be ruled out (HR: 0.42, 95% CI 0.17-1.04). There was no evidence of a decrease in the recidivism risk, in fact the analysis showed a small increase (HR: 1.10, 95% CI 1.02-1.18).

CONCLUSION

For heroin-using offenders, initial contact with treatment services does not appear to reduce the likelihood of a future acquisitive offence.

Effect of ageing and time since first heroin and cocaine use on mortality from external and natural causes in a Spanish cohort of drug users

BACKGROUND

We aimed to assess the effect of ageing and time since first heroin/cocaine use on cause-specific mortality risk and age disparities in excess mortality among heroin (HUs) and cocaine users (CUs) in Spain.

METHODS

A cohort of 15,305 HUs and 11,905 CUs aged 15-49 starting drug treatment during 1997-2007 in Madrid and Barcelona was followed until December 2008. Effects of ageing and time since first heroin/cocaine use were estimated using a competing risk Cox model and the relative and absolute excess mortality compared to the general population through directly age-sex standardized rate ratios (SRRs) and differences (SRDs), respectively.

RESULTS

Mortality risk from natural causes increased with time since first heroin use, whereas that from overdose declined after having peaked in the first quinquennium. Significant effects of time since first cocaine use were not identified, although fatal overdose risk seemed higher in CUs after five years. Mortality risk from natural causes (HUs and CUs), injuries (HUs), and overdoses (CUs) increased with age, the latter without reaching statistical significance. Crude mortality rates from overdoses and injuries remained very high at age 40-59 among both HUs (595 and 217 deaths/100,000 person-years, respectively) and CUs (191 and 88 deaths/100,000 person-years). SRDs from all and natural causes were much higher at age 40-59 than 15-29 in both HUs (2134 vs. 834 deaths/100,000 person-years) and CUs (927 vs. 221 deaths/100,000 person-years), while the opposite occurred with SRRs.

CONCLUSION

The high mortality risk among HUs and CUs at all ages from both external and natural causes, and increased SRDs with ageing, suggest that high-level healthcare and harm reduction services should be established early and maintained throughout the lifetime of these populations.

Association between process measures and mortality in individuals with opioid use disorders

BACKGROUND

Individuals with opioid use disorders have high rates of mortality relative to the general population. The relationship between treatment process and mortality is unknown.

AIM

To examine the association between 7 process measures and 12- and 24-month mortality.

METHODS

Retrospective cohort study of patients with opioid use disorders who received care from the Veterans Administration between October 2006 and September 2007. Logistic regression models were used to examine the association between 12 and 24-month mortality and 7 patient-level process measures, while risk-adjusting for patient characteristics. Process measures included quarterly physician visits, any opioid use disorder pharmacotherapy, continuous pharmacotherapy, psychosocial treatment, Hepatitis B/C and HIV screening, and no prescriptions for benzodiazepines or opioids. We conducted sensitivity analyses to examine the robustness of our findings to an unobserved confounder.

RESULTS

Among individuals with opioid use disorders, not being prescribed opioids or benzodiazepines, receipt of any psychosocial treatment and quarterly physician visits were significantly associated with lower mortality at both 12 and 24 months, but Hepatitis and HIV screening, and measures related to opioid use disorder pharmacotherapy were not. Sensitivity analyses indicated that the difference in the prevalence of an unobserved confounder would have to be unrealistically large given the observed data, or there would need to be a large effect of the confounder, to render these findings non-significant.

CONCLUSIONS AND RELEVANCE

This is the first study to show an association between process measures and mortality in patients with opioid use disorders and provides initial evidence for their use as quality measures.

The extent of and factors associated with self-reported overdose and self-reported receipt of naloxone among people who inject drugs (PWID) in England, Wales and Northern Ireland

BACKGROUND

Overdose is a major cause of death among PWID, and for opioid overdoses naloxone administration can reduce harm. However, globally there is limited national level data on the extent of non-fatal overdose and naloxone uptake. The first national level data on the extent of self-reported overdose and self-reported receipt of naloxone among UK PWID, providing a baseline to monitor the impact of the recent policy change regarding naloxone availability, is presented.

METHODS

Data on self-reported overdose and receipt of naloxone during the preceding year for 2013-2014 from a national survey of PWID was analysed. Participants who reported injecting during the preceding year were included.

RESULTS

Participants (3850) were predominantly male (75%); mean age was 36 years. The most commonly injected drugs were: heroin (91%), crack (45%) and amphetamine (29%). 15% (591) reported overdosing during the preceding year. There were no differences in the proportion reporting overdose by age or gender, but overdose was more common among those who: injected multiple drugs; recently ceased addiction treatment; injected with used needles/syringes; ever had transactional sex; had used a sexual health clinic or emergency department and lived in Wales or Northern Ireland. Among those reporting an overdose during the preceding year, a third reported two to four overdoses and 7.5% five or more overdoses; half reported receiving naloxone. Those reporting naloxone receipt in the preceding year were more likely to: live in Wales or Northern Ireland; ever received used needles/syringes; ever been imprisoned; and less likely to have injected two drug types.

CONCLUSION

These data provide a baseline for monitoring the impact of the 2015 UK policy change to improve take-home naloxone access. Interventions tackling overdose should promote naloxone awareness and access, and target those who; are poly-drug injectors, have ceased treatment, share needles/syringes and whose drug use links to sexual activity.