Health outcomes associated with illicit prescription opioid injection: A systematic review

Buprenorphine versus methadone for the treatment of opioid dependence: a systematic review and meta-analysis of randomised and observational studies

BACKGROUND

Opioid dependence is associated with substantial health and social burdens, and opioid agonist treatment (OAT) is highly effective in improving multiple outcomes for people who receive this treatment. Methadone and buprenorphine are common medications provided as OAT. We aimed to examine buprenorphine compared with methadone in the treatment of opioid dependence across a wide range of primary and secondary outcomes.

METHODS

We did a systematic review and meta-analysis in accordance with GATHER and PRISMA guidelines. We searched Embase, MEDLINE, CENTRAL, and PsycINFO from database inception to Aug 1, 2022; clinical trial registries and previous relevant Cochrane reviews were also reviewed. We included all RCTs and observational studies of adults (aged ≥18 years) with opioid dependence comparing treatment with buprenorphine or methadone. Primary outcomes were retention in treatment at 1, 3, 6, 12, and 24 months, treatment adherence (measured through doses taken as prescribed, dosing visits attended, and biological measures), or extra-medical opioid use (measured by urinalysis and self-report). Secondary outcomes were use of benzodiazepines, cannabis, cocaine, amphetamines, and alcohol; withdrawal; craving; criminal activity and engagement with the criminal justice system; overdose; mental and physical health; sleep; pain; global functioning; suicidality and self-harm; and adverse events. Single-arm cohort studies and RCTs that collected data on buprenorphine retention alone were also reviewed. Data on study, participant, and treatment characteristics were extracted. Study authors were contacted to obtain additional data when required. Comparative estimates were pooled with use of random-effects meta-analyses. The proportion of individuals retained in treatment across multiple timepoints was pooled for each drug. This study is registered with PROSPERO (CRD42020205109).

FINDINGS

We identified 32 eligible RCTs (N=5808 participants) and 69 observational studies (N=323 340) comparing buprenorphine and methadone, in addition to 51 RCTs (N=11 644) and 124 observational studies (N=700 035) that reported on treatment retention with buprenorphine. Overall, 61 studies were done in western Europe, 162 in North America, 14 in north Africa and the Middle East, 20 in Australasia, five in southeast Asia, seven in south Asia, two in eastern Europe, three in central Europe, one in east Asia, and one in central Asia. 1 040 827 participants were included in these primary studies; however, gender was only reported for 572 111 participants, of whom 377 991 (66·1%) were male and 194 120 (33·9%) were female. Mean age was 37·1 years (SD 6·0). At timepoints beyond 1 month, retention was better for methadone than for buprenorphine: for example, at 6 months, the pooled effect favoured methadone in RCTs (risk ratio 0·76 [95% CI 0·67-0·85]; I·=74·2%; 16 studies, N=3151) and in observational studies (0·77 [0·68-0·86]; I·=98·5%; 21 studies, N=155 111). Retention was generally higher in RCTs than observational studies. There was no evidence suggesting that adherence to treatment differed with buprenorphine compared with methadone. There was some evidence that extra-medical opioid use was lower in those receiving buprenorphine in RCTs that measured this outcome by urinalysis and reported proportion of positive urine samples (over various time frames; standardised mean difference -0·20 [-0·29 to -0·11]; I·=0·0%; three studies, N=841), but no differences were found when using other measures. Some statistically significant differences were found between buprenorphine and methadone among secondary outcomes. There was evidence of reduced cocaine use, cravings, anxiety, and cardiac dysfunction, as well as increased treatment satisfaction among people receiving buprenorphine compared with methadone; and evidence of reduced hospitalisation and alcohol use in people receiving methadone. These differences in secondary outcomes were based on small numbers of studies (maximum five), and were often not consistent across study types or different measures of the same constructs (eg, cocaine use).

INTERPRETATION

Evidence from trials and observational studies suggest that treatment retention is better for methadone than for sublingual buprenorphine. Comparative evidence on other outcomes examined showed few statistically significant differences and was generally based on small numbers of studies. These findings highlight the imperative for interventions to improve retention, consideration of client-centred factors (such as client preference) when selecting between methadone and buprenorphine, and harmonisation of data collection and reporting to strengthen future syntheses.

FUNDING

Australian National Health and Medical Research Council.

Intimate partner violence, substance use, and health comorbidities among women: A narrative review

Exposure to intimate partner violence (IPV), including physical, sexual, and psychological violence, aggression, and/or stalking, impacts overall health and can have lasting mental and physical health consequences. Substance misuse is common among individuals exposed to IPV, and IPV-exposed women (IPV-EW) are at-risk for transitioning from substance misuse to substance use disorder (SUD) and demonstrate greater SUD symptom severity; this too can have lasting mental and physical health consequences. Moreover, brain injury is highly prevalent in IPV-EW and is also associated with risk of substance misuse and SUD. Substance misuse, mental health diagnoses, and brain injury, which are highly comorbid, can increase risk of revictimization. Determining the interaction between these factors on the health outcomes and quality of life of IPV-EW remains a critical need. This narrative review uses a multidisciplinary perspective to foster further discussion and research in this area by examining how substance use patterns can cloud identification of and treatment for brain injury and IPV. We draw on past research and the knowledge of our multidisciplinary team of researchers to provide recommendations to facilitate access to resources and treatment strategies and highlight intervention strategies capable of addressing the varied and complex needs of IPV-EW.

Suboptimal nonmedical qualities of primary care linked with care avoidance among people who use drugs in a Canadian setting amid an integrated health care reform

BACKGROUND

People who use unregulated drugs (PWUD) often face significant barriers to-and thereby avoid seeking-health care. In Vancouver, Canada, a neighborhood-wide health care system reform began in 2016 to improve health care delivery and quality. In the wake of this reform, we sought to determine the prevalence of health care avoidance and its association with emergency department use among PWUD in this setting and examine patient-reported nonmedical qualities of health care ("responsiveness").

METHODS

The study derived data from two prospective cohort studies of community-recruited PWUD in Vancouver in 2017-18. Responsiveness was ascertained by the World Health Organizations' standardized measurements and we evaluated seven domains of responsiveness (dignity, autonomy, communication, confidentiality, prompt attention, choice of provider, and quality of basic amenities). The study used Pearson chi-squared test to examine differences in responsiveness between those who did and did not avoid care. The study team used multivariable logistic regression to determine the relationship between care avoidance due to past mistreatment and emergency department use, adjusting for potential confounders.

RESULTS

Among 889 participants, 520 (58.5%) were male, 204 (22.9%) reported avoiding health care, most commonly for chronic pain (47.4%). Overall, 6.6% to 36.2% reported suboptimal levels (i.e., not always meeting the expected quality) across all seven measured domain of responsiveness. Proportions reporting suboptimal qualities were significantly higher among those who avoided care than those who did not across all domains, including care as soon as wanted (51.0% vs. 31.8%), listened to carefully (44.1% vs. 20.4%), and involved in health care decision-making (27.9% vs. 12.7%) (all p < 0.05). In multivariable analyses, avoidance of health care was independently associated with self-reported emergency department use (adjusted odds ratio = 1.49; 95% confidence interval:1.01-2.19).

CONCLUSION

We found that almost a quarter of our sample of PWUD avoided seeking health care due to past mistreatment, and all seven measured domains of responsiveness were suboptimal and linked with avoidance. Individuals who reported avoidance of health care were significantly more likely to report emergency department use. Multi-level interventions are needed to remedy the suboptimal qualities of health care and thereby reduce care avoidance.

Mortality and negative outcomes of opioid use and opioid use disorder: a 6-year follow-up study

BACKGROUND AND AIMS

There is a paucity of data on outcomes of opioid use disorder (OUD) from low- and middle-income countries. We aimed to investigate the mortality as well as negative social and health outcomes in a 6-year follow-up study of a cohort of individuals with opioid use, including those with OUD, in Iran.

DESIGN AND SETTING

Participants with opioid use initially interviewed in late 2011 in the Iranian National Mental Health Survey (IranMHS)-a household survey of 15-64-year-old population-were followed-up in early 2018.

PARTICIPANTS

All respondents (n = 236) who had reported use of any opioids at least five times during the 12-month period prior to the index interview were included in the study.

MEASUREMENTS

Composite International Diagnostic Interview (CIDI) version 2.1 was used for assessment of opioid use and OUD at baseline. Vital status in the follow-up was ascertained through contact with participants/informants, primarily via telephone calls and also through the death registration systems. Weighted incidence rates of negative consequences of opioid use (e.g. incarceration, suicide attempts, violent behavior) were estimated for those who were interviewed.

FINDINGS

Seven (3.3%) of the 236 participants with opioid use including four (3.1%) of the 136 with OUD had died by the time of the follow-up interview, resulting in death rates of 0.49 [95% confidence interval (CI) = 0.21-1.38] and 0.53 (95% CI = 0.16-2.62) per 100 person-years, respectively. Overall, 35.0% of participants with opioid use and 44.0% of those with OUD among the 145 individuals interviewed at follow-up experienced non-fatal serious adverse outcomes.

CONCLUSIONS

In Iran, opioid use and opioid use disorder are associated with increased mortality and other adverse outcomes.

Positive associations between cannabis and alcohol use polygenic risk scores and phenotypic opioid misuse among African-Americans

BACKGROUND

This study examined whether polygenic risk scores (PRS) for lifetime cannabis and alcohol use were associated with misusing opioids, and whether sex differences existed in these relations in an urban, African-American sample.

METHODS

Data were drawn from three cohorts of participants (N = 1,103; 45% male) who were recruited in first grade as part of a series of elementary school-based, universal preventive intervention trials conducted in a Mid-Atlantic region of the U.S. In young adulthood, participants provided a DNA sample and reported on whether they had used heroin or misused prescription opioids in their lifetime. Three substance use PRS were computed based on prior GWAS: lifetime cannabis use from Pasman et al. (2018), heavy drinking indexed via maximum number of drinks from Gelernter et al. (2019), and alcohol consumption from Kranzler et al. (2019).

RESULTS

Higher PRS for lifetime cannabis use, greater heavy drinking, and greater alcohol consumption were associated with heightened risk for misusing opioids among the whole sample. Significant sex by PRS interactions were also observed such that higher PRS for heavy drinking and alcohol consumption were associated with a greater likelihood of opioid misuse among males, but not females.

CONCLUSION

Our findings further elucidate the genetic contributions to misusing opioids by showing that the genetics of cannabis and alcohol consumption are associated with lifetime opioid misuse among young adults, though replication of our findings is needed.

Using administrative data to predict cessation risk and identify novel predictors among new entrants to opioid agonist treatment

BACKGROUND

Longer retention in opioid agonist treatment (OAT) is associated with improved treatment outcomes but 12-month retention rates are often low. Innovative approaches are needed to strengthen retention in OAT. We develop and compare traditional and deep learning-extensions of Cox regression to examine the potential for predicting time in OAT at individuals' first episode entry.

METHODS

Retrospective cohort study in New South Wales, Australia including 16,576 people entering OAT for the first time between January 2006 and December 2017. We develop 12-month OAT cessation prediction models using traditional and deep learning-extensions of the Cox regression algorithm with predictors evaluated from linked administrative datasets. Proportion of explained variation, calibration, and discrimination are compared using 5 × 2 cross-validation.

RESULTS

Twelve-month cessation rate was 58.4%. The largest hazard ratios for earlier cessation from the deep learning model were observed for treatment factors, including private dosing points (HR=1.54, 95% CI=1.49-1.60) and buprenorphine medication (HR=1.43, 95% CI=1.39-1.46). Diagnostic codes for homelessness (HR=1.09, 95% CI=1.04-1.13), outpatient treatment for drug use disorders (HR=1.10, 95% CI=1.06-1.15), and occupant of vehicle accident (HR=1.04, 95% CI=1.01-1.07) from past-year health service presentations were identified as significant predictors of retention. We observed no improvement in performance of the deep learning model over traditional Cox regression.

CONCLUSIONS

Deep learning may be more useful in identifying novel risk factors of OAT retention from administrative data than evaluating individual-level risk. An increased focus on addressing structural issues at the population level and considering alternate models of care may be more effective at improving retention than delivering fully personalised OAT.

Deconstructing the 'cheque effect': short-term changes in injection drug use after receiving income assistance and associated factors

BACKGROUND AND AIMS

Disbursement of income assistance has been temporally associated with intensified drug use and related harms (coined the 'cheque effect'). However, relationships to injection drug use (IDU) remain understudied. We examined short-term 'cheque effects' and associated factors among people who inject drugs (PWID).

DESIGN

Cross-sectional analysis nested within a cohort study.

SETTING

Montreal, Quebec, Canada.

PARTICIPANTS

PWID receiving income assistance, with no employment income. A total of 613 PWID (median age 41, 83% male) contributed 3269 observations from 2011 to 2017.

MEASUREMENTS AND METHODS

At each cohort visit, an interviewer-administered questionnaire captured retrospective reports of injection-related behaviour during the 2-day periods (i) before and (ii) including/after receiving last month's income assistance payment (number of injections; drugs injected; any receptive syringe-sharing). The relative likelihood (odds) and magnitude (rate) of an increase in injection frequency ('cheque effect') were estimated in relation to social and behavioural factors using logistic and negative binomial regression in a covariate-adjusted two-part model.

FINDINGS

Prevalence of IDU and syringe-sharing were, respectively, 1.80 and 2.50 times higher in the days following versus preceding cheque receipt (P < 0.001). Among people with past-month IDU, most observations showed increased injection frequency (52%) or no change in injection frequency (44%). The likelihood of a 'cheque effect' was positively associated with cocaine injection [versus injection of other substances, odds ratio (OR) = 2.639, 95% confidence interval (CI) = 2.04-3.41], unstable housing (OR = 1.272, 95% CI = 1.03-1.57) and receiving opioid agonist therapy (OR =1.597, 95% CI = 1.27-2.00) during the same month. Magnitude of the 'cheque effect' was positively associated with cocaine injection [rate ratio (RR) = 1.795, 95% CI = 1.43-2.16], unstable housing (RR = 1.198, 95% CI = 1.02-1.38) and frequent injection (RR = 2.938, 95% CI = 2.43-3.44), but inversely associated with opioid agonist therapy (RR = 0.817, 95% CI = 0.68-0.95) and prescription opioid injection (RR = 0.794, 95% CI = 0.66-0.93).

CONCLUSION

Among people who inject drugs in Montreal, Canada, injection drug use and receptive syringe-sharing appear to be more prevalent in the 2 days after versus before receiving income assistance. The odds and rate of individual-level increases in injection frequency appear to be positively associated with cocaine injection (versus injection of other substances) and unstable housing.

Risk factors of infective endocarditis in persons who inject drugs

BACKGROUND

The rising incidence of infective endocarditis (IE) among people who inject drugs (PWID) has been a major concern across North America. The coincident rise in IE and change of drug preference to hydromorphone controlled-release (CR) among our PWID population in London, Ontario intrigued us to study the details of injection practices leading to IE, which have not been well characterized in literature.

METHODS

A case-control study, using one-on-one interviews to understand risk factors and injection practices associated with IE among PWID was conducted. Eligible participants included those who had injected drugs within the last 3 months, were > 18  years old and either never had or were currently admitted for an IE episode. Cases were recruited from the tertiary care centers and controls without IE were recruited from outpatient clinics and addiction clinics in London, Ontario.

RESULTS

Thirty three cases (PWID IE+) and 102 controls (PWID but IE-) were interviewed. Multivariable logistic regressions showed that the odds of having IE were 4.65 times higher among females (95% CI 1.85, 12.28; p = 0.001) and 5.76 times higher among PWID who did not use clean injection equipment from the provincial distribution networks (95% CI 2.37, 14.91; p < 0.001). Injecting into multiple sites and heating hydromorphone-CR prior to injection were not found to be significantly associated with IE. Hydromorphone-CR was the most commonly injected drug in both groups (90.9% cases; 81.4% controls; p = 0.197).

DISCUSSION

Our study highlights the importance of distributing clean injection materials for IE prevention. Furthermore, our study showcases that females are at higher risk of IE, which is contrary to the reported literature. Gender differences in injection techniques, which may place women at higher risk of IE, require further study. We suspect that the very high prevalence of hydromorphone-CR use made our sample size too small to identify a significant association between its use and IE, which has been established in the literature.

Drug Misuse and Hepatitis C Virus Infection Profiles for Three Generations of Patients Being Monitored for Prescription Drug Adherence

Objectives:

Two epidemics in the United States are related: opioid drug injection and hepatitis C virus (HCV) infection. This study quantifies the relationship between illicit/prescription drug misuse and HCV infection in 3 population generations: baby boomers (born 1945–1965, inclusive), pre-baby boomers, and post-baby boomers.

Methods:

This retrospective study included prescription drug consistency (March–December 2015) and HCV (2011–2015) patient test results performed at a large national clinical reference laboratory. HCV positivity, drug use consistency/inconsistency with prescribed drug information, type of inconsistent use, and inconsistent use of individual drug classes were assessed.

Results:

This study evaluated 39,231 prescription drug monitoring and HCV sets of test results from 18,410 patients. Of these patients, 25.1% tested positive for HCV and 57.3% demonstrated drug test results that were inconsistent with the prescribed medication(s). The types of drug test inconsistency differed substantially between HCV-positive and -negative patients, particularly testing positive for both non-prescribed drugs and prescribed drugs. Specimens from HCV-positive baby boomer and post-baby boomers demonstrated non-prescribed use of opioids and many other drug classes more often than from HCV-negative patients.

Conclusions:

The rates of inconsistent drug test results and types of drugs misused suggest that HCV-positive patients are more likely than HCV-negative patients to display high-risk behavior, even beyond opioid use. This difference is most pronounced in the post-baby boomer generation. Healthcare professionals should consider these patterns and how they differ by generation when monitoring for both prescription and illicit drugs, the results of which can impact treatment decisions including prescribing analgesics.

Prescription opioid injection among young people who inject drugs in New York City: a mixed-methods description and associations with hepatitis C virus infection and overdose

Aim

Evidence is emerging that prescription opioid (PO) injection is associated with increased health risks. This mixed-methods study compares the mechanics of PO and heroin injection and examines the demographic and drug-related correlates of lifetime PO injection in a sample of young people who inject drugs (PWID) in New York City (NYC).

Methods

Qualitative analysis of 46 semi-structured interviews with young adult opioid users ages 18–32. Interview segments describing PO injection were analyzed for common themes. Quantitative analysis of structured interviews with 539 young adult opioid users ages 18–29 recruited via respondent-driven sampling (RDS). Analyses are based on the subsample of 353 participants (65%) who reported having ever injected drugs. All variables were assessed via self-report, except hepatitis C virus status, which was established via rapid antibody testing.

Results

Participants described injecting POs and reported that preparing abuse-deterrent pills for injection is especially cumbersome, requiring extended manipulation and large amounts of water. Injecting POs, in contrast to injecting heroin, requires repeated injections per injection episode. Among RDS-recruited participants, the majority of injectors reported injecting POs, sporadically (33%) or regularly (26%), but often infrequently (≤ 7 days/month). In separate multivariable analyses controlling for syringe- and cooker-sharing, ever injecting POs was a significant predictor of testing HCV antibody-positive (AOR = 2.97) and lifetime experience of non-fatal overdose (AOR = 2.51). Ever injecting POs was independently associated with lifetime homelessness (AOR = 2.93) and having grown up in a middle-income ($51,000–100,000/year vs. ≤ $50,000/year; AOR = 1.86) or a high-income household (> $100,000/year vs. ≤ $50,000/year; AOR = 2.54).

Conclusions

Even in an urban environment like NYC with widespread heroin access, most young PWID have injected POs, although less frequently than heroin. PO injection involves practices that are known to increase risk for blood-borne viral infection (e.g., repeated injections) and predicted testing HCV-positive, as well as overdose. PO injection may also serve as a marker for a subgroup of PWID at elevated risk for multiple drug use-related comorbidities. Programs that provide prevention services to PWID need to tailor harm reduction measures and messaging to the specific practices and harms associated with the injection of POs.

Examining Social-Ecological Factors in Developing the Louisville Metro Department of Public Health and Wellness Syringe Exchange Program

Amid an opioid epidemic and increasing HIV and hepatitis C virus (HCV) concerns, the Louisville Metro Department of Public Health and Wellness developed syringe exchange programming (SEP) to reduce HIV and HCV transmission, increase linkage to health care, and provide health education to clients in Louisville, Kentucky. We describe organizational, community, and policy factors contributing to SEP development. Approximately 8000 clients received SEP services from June 2015 to December 2016. Coalition building, timely advocacy, and media engagement are integral to successful SEP development and uptake.

Drug-related mortality after discharge from treatment: A record-linkage study of substance abuse clients in Texas, 2006-2012

BACKGROUND

Patients have higher mortality immediately after substance abuse treatment discharge, but there are few data on post-discharge mortality differences across treatment modalities.

METHODS

A retrospective cohort study examined individuals discharged from substance abuse treatment during 2006-2012 and probabilistically matched treatment records to death records. Logistic regression examined associations between drug-related death (DRD) and demographics; route, frequency, and classes of drugs abused; and treatment. Primary outcome was DRD during post-discharge days 0-28; secondary outcomes examined DRD during days 29-90 and 91-365.

RESULTS

We examined 178,749 patients discharged from 254,814 treatment episodes. There were 97 DRD during days 0-28 (4.1/1000 person-years), 115 DRD during days 29-90 (2.6/1000 person-years; IRR 0.6 [95% CI 0.5-0.8]), and 293 DRD during days 91-365 (1.9/1000 person-years; IRR 0.5 [0.4-0.6]). Higher 28-day DRD was associated with abuse of opioids (aOR 2.5 [1.4-4.4]), depressants (aOR 2.0 [1.2-3.4]), or alcohol (aOR 1.7 [1.1-2.6]); and opioid injection (aOR 2.2 [1.3-3.7]). Lower DRD was associated with treatment completion (aOR 0.6 [0.4-0.9]), female sex (aOR 0.6 [0.4-0.8]), and employment (aOR 0.5 [0.3-0.9]). Among all patients, DRD rates were higher following residential (IRR 2.6, [1.6-4.2]) and detoxification (IRR 2.9, [1.7-4.9]) treatment compared to outpatient. Patients with prior opioid abuse had higher 28-day DRD after outpatient (6.7/1000 person-years; IRR 4.1 [1.8-9.1]), residential (13.6/1000 person-years; IRR 4.2 [2.2-8.2]), and detoxification (8.8/1000 person-years; IRR 3.2 [1.2, 8.5]) compared to those without.

CONCLUSIONS

Drug-related mortality is highest during days 0-28 after discharge, especially following residential and detoxification treatment. Opioid abuse is strongly associated with early post-discharge mortality.

Global patterns of opioid use and dependence: harms to populations, interventions, and future action

We summarise the evidence for medicinal uses of opioids, harms related to the extramedical use of, and dependence on, these drugs, and a wide range of interventions used to address these harms. The Global Burden of Diseases, Injuries, and Risk Factors Study estimated that in 2017, 40·5 million people were dependent on opioids (95% uncertainty interval 34·3-47·9 million) and 109 500 people (105 800-113 600) died from opioid overdose. Opioid agonist treatment (OAT) can be highly effective in reducing illicit opioid use and improving multiple health and social outcomes-eg, by reducing overall mortality and key causes of death, including overdose, suicide, HIV, hepatitis C virus, and other injuries. Mathematical modelling suggests that scaling up the use of OAT and retaining people in treatment, including in prison, could avert a median of 7·7% of deaths in Kentucky, 10·7% in Kiev, and 25·9% in Tehran over 20 years (compared with no OAT), with the greater effects in Tehran and Kiev being due to reductions in HIV mortality, given the higher prevalence of HIV among people who inject drugs in those settings. Other interventions have varied evidence for effectiveness and patient acceptability, and typically affect a narrower set of outcomes than OAT does. Other effective interventions focus on preventing harm related to opioids. Despite strong evidence for the effectiveness of a range of interventions to improve the health and wellbeing of people who are dependent on opioids, coverage is low, even in high-income countries. Treatment quality might be less than desirable, and considerable harm might be caused to individuals, society, and the economy by the criminalisation of extramedical opioid use and dependence. Alternative policy frameworks are recommended that adopt an approach based on human rights and public health, do not make drug use a criminal behaviour, and seek to reduce drug-related harm at the population level.

Causes of Excess Mortality in Veterans Treated for Posttraumatic Stress Disorder

INTRODUCTION

Published research indicates that posttraumatic stress disorder (PTSD) is associated with increased mortality. However, causes of death among treatment-seeking patients with PTSD remain poorly characterized. The study objective was to describe causes of death among Veterans with PTSD to inform preventive interventions for this treatment population.

METHODS

A retrospective cohort study was conducted for all Veterans who initiated PTSD treatment at any Department of Veterans Affairs Medical Center from fiscal year 2008 to 2013. The primary outcome was mortality within the first year after treatment initiation. In 2018, collected data were analyzed to determine leading causes of death. For the top ten causes, standardized mortality ratios (SMRs) were calculated from age- and sex-matched mortality tables of the U.S. general population.

RESULTS

A total of 491,040 Veterans were identified who initiated PTSD treatment. Mean age was 48.5 (±16.0) years, 90.7% were male, and 63.5% were of white race. In the year following treatment initiation, 1.1% (5,215/491,040) died. All-cause mortality was significantly higher for Veterans with PTSD compared with the U.S. population (SMR=1.05, 95% CI=1.02, 1.08, p<0.001). Veterans with PTSD had a significant increase in mortality from suicide (SMR=2.52, 95% CI=2.24, 2.82, p<0.001), accidental injury (SMR=1.99, 95% CI=1.83, 2.16, p<0.001), and viral hepatitis (SMR=2.26, 95% CI=1.68, 2.93, p<0.001) versus the U.S.

POPULATION

Of those dying from accidental injury, more than half died of poisoning (52.3%, 325/622).

CONCLUSIONS

Veterans with PTSD have an elevated risk of death from suicide, accidental injury, and viral hepatitis. Preventive interventions should target these important causes of death.

Structure-Based Approach for the Prediction of Mu-opioid Binding Affinity of Unclassified Designer Fentanyl-Like Molecules

Three quantitative structure-activity relationship (QSAR) models for predicting the affinity of mu-opioid receptor (μOR) ligands have been developed. The resulted models, exploiting the accessibility of the QSAR modeling, generate a useful tool for the investigation and identification of unclassified fentanyl-like structures. The models have been built using a set of 115 molecules using Forge as a software, and the quality was confirmed by statistical analysis, resulting in being effective for their predictive and descriptive capabilities. The three different approaches were then combined to produce a consensus model and were exploited to explore the chemical landscape of 3000 fentanyl-like structures, generated by a theoretical scaffold-hopping approach. The findings of this study should facilitate the identification and classification of new μOR ligands with fentanyl-like structures.

The effect of forensic events on health status and housing stability among homeless and vulnerably housed individuals: A cohort study

We sought to characterize the association between a forensic event (arrest or incarceration) with housing vulnerability and mental and physical health status over a four-year follow-up among a cohort of homeless and vulnerably housed individuals in Vancouver, Toronto and Ottawa. Data were obtained from the Health and Housing in Transition Study, a prospective cohort study of homeless and vulnerably housed individuals between 2009 and 2012. Participants were interviewed in-person at baseline (N = 1190) and at four annual follow-up time points. We used generalized estimating equations to characterize the independent associations between a forensic event and the number of residential moves and SF-12 physical and mental health component scores over the four-year follow-up period. We analyzed data from 1173 homeless and vulnerably housed participants. Forensic events were reported by 446 participants at baseline. In multivariate analyses, a history of forensic event in the preceding twelve months was independently associated with an increased number of residential moves over the four-year follow-up period (ARR 1.24; 95% CI 1.19–1.3). It was not, however, independently associated with a change in physical or mental health status (respective ß-estimates; 95% CI: -0.34; -1.02, 0.34, and -0.69; -1.5, 0.2). Female gender and a history of problematic substance use were significantly associated with all three primary outcomes. This suggests arrest or incarceration is associated with increased housing vulnerability. The results underline the importance of supporting individuals experiencing arrest or incarceration with post-release planning in order to obtain stable housing after discharge.

Reprint of Trends and key correlates of prescription opioid injection misuse in the United States

BACKGROUND

Despite concerns over increasing harms associated with prescription opioid injection misuse, there is a paucity of research on the magnitude, characteristics, injection practices, and syringe sources for people who inject prescription opioids; limiting the implementation of targeted policy and programmatic initiatives.

MATERIALS AND METHODS

Data from the 2003 through 2014 National Surveys on Drug Use and Health were used to estimate prescription opioid injection trends and examine risky injection practices and syringe sources for people who inject prescription opioids. Multivariable logistic regression was used to identify characteristics associated with prescription opioid injection.

RESULTS

Among people 12years or older, the rate of prescription opioid injection misuse increased from 1.6 per 1000 in 2003-2005 to 2.7 per 1000 in 2012-2014 (p value for trend <0.05). Groups with increased odds of prescription opioid injection included: males, non-Hispanic whites, having an annual household income <$50,000, the uninsured, people with Medicaid, and people with past-year use disorders for cocaine, heroin, or prescription opioids. Risky injection practices such as reusing a needle and sharing needles were common among people with a history of prescription opioid injection misuse.

CONCLUSION

This study found significant increases in prescription opioid injection misuse trends in the U.S. These findings underscore the need to bring to scale evidence-based interventions to increase the provision of medication-assisted treatment for opioid use disorders and expand access to comprehensive risk-reduction services for people who inject drugs.

Empirical Studies Addressing the Opioid Epidemic: An Urgent Call for Research

Opioid misuse has become one of the most pressing public health problems facing the country. In this article, we briefly review literature regarding the opioid epidemic in the United States and the negative consequences of opioid use disorder. We provide information regarding treatment and relapse using a variety of intervention approaches. We call for research on people with opioid use disorder that can contribute to a variety of areas: improving medication-assisted treatment, addressing chronic pain, examination of adjunctive behavioral interventions, overdose, high risk behaviors and infections, pregnancy, diverse populations, and other psychological factors. Collectively addressing these crucial areas of research will advance the field and help alleviate suffering and prevent death from opioid use disorder.

Trends and key correlates of prescription opioid injection misuse in the United States

BACKGROUND

Despite concerns over increasing harms associated with prescription opioid injection misuse, there is a paucity of research on the magnitude, characteristics, injection practices, and syringe sources for people who inject prescription opioids; limiting the implementation of targeted policy and programmatic initiatives.

MATERIALS AND METHODS

Data from the 2003 through 2014 National Surveys on Drug Use and Health were used to estimate prescription opioid injection trends and examine risky injection practices and syringe sources for people who inject prescription opioids. Multivariable logistic regression was used to identify characteristics associated with prescription opioid injection.

RESULTS

Among people 12years or older, the rate of prescription opioid injection misuse increased from 1.6 per 1000 in 2003-2005 to 2.7 per 1000 in 2012-2014 (p value for trend <0.05). Groups with increased odds of prescription opioid injection included: males, non-Hispanic whites, having an annual household income <$50,000, the uninsured, people with Medicaid, and people with past-year use disorders for cocaine, heroin, or prescription opioids. Risky injection practices such as reusing a needle and sharing needles were common among people with a history of prescription opioid injection misuse.

CONCLUSION

This study found significant increases in prescription opioid injection misuse trends in the U.S. These findings underscore the need to bring to scale evidence-based interventions to increase the provision of medication-assisted treatment for opioid use disorders and expand access to comprehensive risk-reduction services for people who inject drugs.

Characteristics of persons who inject drugs and who witness opioid overdoses in Vietnam: a cross-sectional analysis to inform future overdose prevention programs

BACKGROUND

Persons who use opioids have a high risk of overdose and associated mortality. In Vietnam, little is known about the characteristics of this population and the persons who are witness to those overdoses. One approach to combatting fatal overdose has been the use of peer interventions in which a friend or injecting partner administers overdose reversal medication, but availability in Vietnam of these medications is limited to pilot programs with aims to expand in the future (Le Minh and V.F. Go, Personal Communication, 2016). The primary objective of this paper is to explore the characteristics associated with witnessing three or more overdoses in a lifetime.

METHODS

This cross-sectional analysis used baseline data from a four-arm randomized control trial conducted in Thai Nguyen, Vietnam, known as the Prevention for Positives project. One thousand six hundred seventy-three PWID were included in the analysis. We conducted bivariable and multivariable logistic regression to identify characteristics associated with witnessing three or more overdoses in a lifetime. Characteristics explored included education, employment, marital status, risky drug use behaviors, locations for accessing syringes, recent overdose, history of incarceration, drug treatment, and having slept outside in the past 3 months.

RESULTS

Seventy-two percent (n = 1203) of participants had witnessed at least one overdose in their lifetime, and 46% had witnessed three or more overdoses (n = 765). In the multivariable model, having less than secondary education (AOR 0.70; 95% CI 0.57, 0.86), having slept outside in the past 3 months (AOR 1.77; 95% CI 1.31, 2.40), having a history of incarceration (AOR 1.33; 95% CI 1.07, 1.65), having a history of drug treatment (AOR 1.41; 95% CI 1.12, 1.77), experiencing a recent non-fatal overdose (AOR 3.84; 95% CI 2.36, 6.25), injecting drugs daily (AOR 1.79; 95% CI 1.45, 2.20), receptive needle sharing (AOR 1.30; 95% CI 1.04, 1.63), and number of years injecting (AOR 1.04; 95% CI 1.02, 1.07) were significantly associated with witnessing three or more overdoses.

CONCLUSIONS

Targeted interventions are needed to train persons witnessing an overdose to administer overdose-reversal medication. This includes targeting persons prior to release from prisons, drug treatment centers, and those accessing syringe exchange programs. Additional research should assess the burden of witnessing an overdose as well as locations for medication distribution. Assessments of the training capacity and needs for implementing these programs among drug using peers in Vietnam are of the utmost importance.

"I love having benzos after my coke shot": The use of psychotropic medication among cocaine users in downtown Montreal

BACKGROUND

Cocaine abuse is a major public health issue due to its role in the HIV and hepatitis C virus (HCV) epidemics in North America. A significant area of concern among people who use cocaine (PWUC), injected or smoked, is their frequent misuse of prescription drugs, particularly psychotropic medication (PM), such as tranquilizers, sedatives, stimulants, and antipsychotics. This paper aims to describe and understand practices of PM use among PWUC in downtown Montreal.

METHOD

Ethnographic methods including participant observation and semi-structured interviews were used in an iterative manner.

RESULTS

Two thirds of the 50 participants were male. They ranged in age from 20 to 60 and most were homeless. A significant proportion of them reported polydrug use patterns that included frequent concomitant opioid use (heroin and/or prescription opioids (PO)). Benzodiazepine-based tranquilizers and the atypical antipsychotic quetiapine were the most frequently used PM. Routes of PM administration were oral, nasal and, to a lesser degree, intravenous. Five main PM use practices were identified: 1) "downers" from cocaine high (benzodiazepines and quetiapine); 2) enhancers of heroin/PO effects (benzodiazepines); 3) reducers or suppressors of heroin/PO withdrawal symptoms (benzodiazepines); 4) enablers of a different type of "trip" (benzodiazepines); and 5) treatment for mental and physical problems (benzodiazepines and quetiapine).

CONCLUSION

PM use practices showed several complementary functions that PM fulfill in a context of polydrug use. The soothing and stimulating effects of PM reinforce the patterns of drug use among participants, posing various risks including overdose, HIV/HCV transmission, PM dependence and accidents. The results highlight the need for clinicians to assess clients' substance use patterns when prescribing PM and to question PWUC about PM use. The findings also underline certain unmet service needs in relation to overdose, HIV/HCV and mental health prevention/treatment among cocaine users.

Increases in prescription opioid injection abuse among treatment admissions in the United States, 2004-2013

BACKGROUND

The 2015 HIV outbreak in Indiana associated with prescription opioid injection coupled with rising rates of hepatitis C, especially in areas with long-standing opioid abuse, have raised concerns about prescription opioid injection. However, research on this topic is limited. We assessed trends in treatment admissions reporting injection, smoking, and inhalation abuse of prescription opioids and examined characteristics associated with non-oral routes of prescription opioid abuse in the U.S.

METHODS

Prescription opioid abuse treatment admissions in the 2004-2013 Treatment Episode Data Set were used to calculate counts and percentages of prescription opioid treatment admissions reporting oral, injection, or smoking/inhalation abuse overall, by sex, age, and race/ethnicity. Multivariable multinomial logistic regression was used to identify demographic and substance use characteristics associated with injection or smoking/inhalation abuse.

RESULTS

From 2004-2013, oral abuse decreased from 73.1% to 58.9%; injection abuse increased from 11.7% to 18.1%; and smoking/inhalation abuse increased from 15.3% of admissions to 23.0%. Among treatment admissions, the following were associated with injection abuse: male sex, 18-54 year-olds, non-Hispanic whites, non-Hispanic other, homeless or dependent living, less than full-time work, living in the Midwest or South, ≥1 prior treatment episodes, younger age of first opioid use, and reporting use of cocaine/crack, marijuana, heroin, or methamphetamine.

CONCLUSIONS

The proportion of treatment admissions reporting prescription opioid injection and smoking/inhalation abuse increased significantly in the U.S. between 2004 and 2013. Expanding prevention efforts as well as access to medication-assisted treatment and risk reduction services for people who inject drugs is urgently needed.

Trends in Opioid Use Disorder Diagnoses and Medication Treatment Among Veterans With Posttraumatic Stress Disorder

OBJECTIVE

Despite long-standing interest in posttraumatic stress disorder (PTSD) and opioid use disorder comorbidity, there is a paucity of data on the prevalence of opioid use disorder in patients with PTSD. Therefore, there is limited understanding of the use of medications for opioid use disorder in this population. We determined the prevalence of diagnosed opioid use disorder and use of medications for opioid use disorder in a large cohort of patients with PTSD.

METHODS

We obtained administrative and pharmacy data for veterans who initiated PTSD treatment in the Department of Veterans Affairs (VA) between 2004 and 2013 (N = 731,520). We identified those with a comorbid opioid use disorder diagnosis (2.7%; n = 19,998) and determined whether they received a medication for opioid use disorder in the year following their initial clinical PTSD diagnosis (29.6%; n = 5,913). Using logistic regression, we determined the predictors of receipt of opioid use disorder medications.

RESULTS

Comorbid opioid use disorder diagnoses increased from 2.5% in 2004 to 3.4% in 2013. Patients with comorbid opioid use disorder used more health services and had more comorbidities than other patients with PTSD. Among patients with PTSD and comorbid opioid use disorder, use of medications for opioid use disorder increased from 22.6% to 35.1% during the same time period. Growth in the use of buprenorphine (2.0% to 22.7%) was accompanied by relative decline in use of methadone (19.3% to 12.7%). Patients who received buprenorphine were younger and more likely to be rural, White, and married. Patients who received methadone were older, urban, unmarried, from racial and ethnic minorities, and more likely to see substance abuse specialists. While use of naltrexone increased (2.8% to 8.6%), most (87%) patients who received naltrexone also had an alcohol use disorder. Controlling for patient factors, there was a substantial increase in the use of buprenorphine, a substantial decrease in the use of methadone, and no change in use of naltrexone across years.

CONCLUSIONS

Opioid use disorder is an uncommon but increasing comorbidity among patients with PTSD. Patients entering VA treatment for PTSD have their opioid use disorder treated with opioid agonist treatments in large and increasing numbers. There is a need for research both on the epidemiology of opioid use disorder among patients with PTSD and on screening for opioid use disorder.

Willingness to use a supervised injection facility among young adults who use prescription opioids non-medically: a cross-sectional study

Background

Supervised injection facilities (SIFs) are legally sanctioned environments for people to inject drugs under medical supervision. SIFs currently operate in ten countries, but to date, no SIF has been opened in the USA. In light of increasing overdose mortality in the USA, this study evaluated willingness to use a SIF among youth who report non-medical prescription opioid (NMPO) use.

Methods

Between January 2015 and February 2016, youth with recent NMPO use were recruited to participate in the Rhode Island Young Adult Prescription Drug Study (RAPiDS). We explored factors associated with willingness to use a SIF among participants who had injected drugs or were at risk of initiating injection drug use (defined as having a sex partner who injects drugs or having a close friend who injects).

Results

Among 54 eligible participants, the median age was 26 (IQR = 24–28), 70.4% were male, and 74.1% were white. Among all participants, when asked if they would use a SIF, 63.0% answered “Yes”, 31.5% answered “No”, and 5.6% were unsure. Among the 31 participants reporting injection drug use in the last six months, 27 (87.1%) reported willingness to use a SIF; 15 of the 19 (78.9%) who injected less than daily reported willingness, while all 12 (100.0%) of the participants who injected daily reported willingness. Compared to participants who were unwilling or were unsure, participants willing to use a SIF were also more likely to have been homeless in the last six months, have accidentally overdosed, have used heroin, have used fentanyl non-medically, and typically use prescription opioids alone.

Conclusions

Among young adults who use prescription opioids non-medically and inject drugs or are at risk of initiating injection drug use, more than six in ten reported willingness to use a SIF. Established risk factors for overdose, including homelessness, history of overdose, daily injection drug use, heroin use, and fentanyl misuse, were associated with higher SIF acceptability, indicating that young people at the highest risk of overdose might ultimately be the same individuals to use the facility. Supervised injection facilities merit consideration to reduce overdose mortality in the USA.

Electronic supplementary material

The online version of this article (doi:10.1186/s12954-017-0139-0) contains supplementary material, which is available to authorized users.

High risk injecting behaviour among people who inject pharmaceutical opioids in Australia

BACKGROUND

Use of opioid analgesic medicines has doubled globally over the past decade, with a concomitant increase in prevalence of injection of pharmaceutical opioids (PO), including in Australia. This study investigates types of PO injected, methods used to prepare PO for injection and correlates of recent (last 6 months) PO injection among a large national sample of people who inject drugs (PWID).

METHODS

The Australian NSP Survey (ANSPS), conducted annually at ∼50 NSP services across Australia, consists of a brief self-administered questionnaire and provision of a capillary dried blood spot for HIV and hepatitis C antibody testing. Data from 2014 were used to conduct univariable and multivariable logistic regression analysis to determine factors independently associated with recent injection of PO.

RESULTS

Among 1488 ANSPS respondents who were identified as opioid injectors, 57% (n=848) reported injection of PO in the previous six months. The majority of PO injectors (85%) reported filtering PO prior to injection, although use of efficacious wheel filters was relatively rare (11%). Correlates of POs injection included daily injection (AOR=1.65, 95% CI 1.31-2.08), receptive sharing of syringes (AOR=2.00, 95% CI 1.43-2.78), receptive sharing of drug preparation equipment (AOR=1.55, 95% CI 1.19-2.01), drug overdose in the previous year (AOR=1.81, 95% CI 1.36-2.42) and residence in inner regional (AOR=3.27, 95% CI 2.21-5.23) or outer regional/remote (AOR=5.50, 95% CI 3.42-8.84) areas of Australia.

CONCLUSION

PO injection is geographically widespread among Australian PWID and takes place in the context of poly-drug use. People who inject POs are at high risk of overdose, injection related injury and disease and blood borne viral infections. Harm reduction services that target this group, including in non-urban areas, should deliver health education regarding PO-specific overdose risks, the requirement to adequately filter PO before injection and to ensure that both naloxone and specialist pill filters are readily accessible.

The role of living context in prescription opioid injection and the associated risk of hepatitis C infection

BACKGROUND AND AIMS

Prescription opioid injection (POI) is a leading risk factor for hepatitis C virus (HCV). Residential context relates to high‐risk injection behaviour. This study assessed whether residence in the inner city (versus surrounding areas in Montréal Island) modified the effects of correlates of POI or the relationship between POI and HCV incidence.

DESIGN

Prospective cohort study.

SETTING

Montréal, Canada.

PARTICIPANTS

A total of 854 people who inject drugs (18% female, 25% age < 30 years), living on Montréal Island, were interviewed every 3–6 months from 2004 to 2012.

MEASUREMENTS

Study visits included HCV antibody testing and an interviewer‐administered questionnaire. Generalized estimating equations were used to test whether place of residence modified the effects of correlates of POI. Cox regression was used to test whether place of residence modified the relationship between POI and HCV incidence.

FINDINGS

At baseline, inner‐city participants were more likely to report POI in the past month (40 versus 25%, P < 0.001). The association between POI and heroin injection, syringe sharing and sharing of injecting equipment varied according to place of residence and was greater in the inner city. The hazard of HCV infection associated with POI was greater among inner‐city participants compared to those in the surrounding areas [adjusted hazard ratio (HR) = 3.38, 95% confidence interval (CI) = 1.88–6.07 versus HR = 1.26, 95% CI = 0.65–2.42, P = 0.025].

CONCLUSIONS

Among people who inject prescription opioids in Montréal, Canada, those who live in inner‐city areas are more likely to engage in injecting‐related risk behaviours and have a higher risk of hepatitis C virus infection than those who live in the suburbs.