Drug use patterns in the presence of crack in downtown Montréal

Trends in toxicological findings in unintentional opioid or stimulant toxicity deaths in Québec, Canada, 2012-2021: Has Québec entered a new era of drug-related deaths?

INTRODUCTION

We aimed to describe rates and toxicological findings of unintentional opioid and stimulant toxicity deaths, 2012-2021.

METHODS

The dataset included accidental deaths determined by the Coroner to be due to opioids or stimulants. We calculated annual crude mortality rates and described combinations of drugs identified in toxicological examinations of these deaths. We described temporal trends in the detection of specific opioids, stimulants, benzodiazepines (including novel benzodiazepines), gabapentinoids and z-drugs in deaths due to opioids and stimulants.

RESULTS

Mortality rates increased over time, reaching their peak in 2020 and remaining high in 2021. In deaths due to opioids, there was a decline in the proportion of deaths involving pharmaceutical opioids after 2019, and a corresponding increase in the proportion of deaths with fentanyl detected. Benzodiazepines were often present in deaths due to opioids, with novel benzodiazepines increasing rapidly from 2019 onwards. Cocaine was the most frequently detected drug in deaths due to stimulants, but amphetamine/methamphetamine was detected in around half of all stimulant deaths from 2016 onwards.

DISCUSSION AND CONCLUSIONS

Despite availability of a multitude of overdose prevention interventions, mortality rates due to drug toxicity have increased in Québec. Toxicological findings of these deaths suggest concerning shifts in the illicit drug market, with Québec potentially having entered a new era of elevated overdose mortality. Intervention scale-up is essential, but unlikely to be sufficient, to reduce drug-related mortality. Policy reform to address the root causes of drug toxicity deaths, including an unpredictable drug supply, strained health systems and socio-economic precarity, is essential.

HIV and HCV seroincidence, associated factors and drug use in people who inject drugs, SurvUDI network, eastern central Canada, 1995-2020

BACKGROUND

The SurvUDI network is a biobehavioural survey among people who inject drugs (PWID) in Eastern Central Canada.

OBJECTIVES

The objectives were to describe HIV and HCV seroincidence trends, associated factors and changes in drug use behaviours.

METHODS

The network was initiated in 1995 and targets hard-to-reach, mostly out-of- treatment PWID. Participants were recruited mostly in harm reduction programs, completed an interviewer-administered questionnaire, provided a sample of gingival exudate for HIV and HCV antibody testing and were identified using an encrypted code allowing identification of multiple participations. Time trends were examined for HIV and HCV seroincidence, selected characteristics and behaviours. Cox proportional hazard regression was used to examine factors associated to HIV and HCV seroincidence.

RESULTS

Between January 1995 and March 2020, 15,907 individuals have completed 31,051 questionnaires. HIV seroincidence decreased significantly from 5.0 per 100 person-years (p-y) in 1995 to 0.4 per 100 p-y in 2018. HCV seroincidence also decreased significantly between 1998 and 2011. The use of syringes already used by someone else decreased significantly, from 43.4 % in 1995 to 12.4 % in 2019, as well as the use of equipment other than syringe already used by someone else. Cocaine/crack injection decreased significantly while "opioids other than heroin" injection increased, concomitant to daily injection. Injection with syringes already used by someone else and cocaine as the most often injected drug were significantly associated with HIV seroincidence (1995-2020). Injected opioid other than heroin, injected cocaine/crack, injected 100 or more times in the past month, injected for less than 3 years, injected with syringes or equipment already used by someone else, injected with someone else and reported client sex partners were significantly associated with HCV seroincidence (2004-2020).

CONCLUSION

HIV seroincidence and syringe/equipment sharing behaviour trends are encouraging, but HCV seroincidence remains high.

Recent increases in crack injection and associated risk factors among people who inject psychoactive drugs in England and Wales

BACKGROUND

Crack use is higher in the United Kingdom (UK) than other European countries. Crack is a stimulant with a short half-life, requiring frequent injection to maintain its euphoric effects, thus increasing the risk of blood borne viruses (BBVs) and skin and soft tissue infections (SSTIs). We assessed trends in the prevalence of current crack injection among people who inject drugs (PWID) and investigated harms and other factors associated with its use.

METHODS

We used data from the annual Unlinked Anonymous Monitoring Survey of PWID, which recruits people who have ever injected psychoactive drugs through specialist services. Participants provide a biological sample and self-complete a questionnaire. We included participants from England and Wales who had injected in the past month. We examined trends in crack injection over time (2011-2021) and factors associated with crack injection using multivariable logistic regression (2019-2021).

RESULTS

The proportion of people self-reporting crack injection in the past month almost doubled between 2011-2020/21, from 34 % (416/1237) to 57 % (483/850). Crack injection was more frequently reported by males than females (adjusted odds ratio 1.46, 95 % confidence interval: 1.15-1.87) and injected alongside heroin (6.67, 4.06-10.97) more frequently than alone. Crack injection was independently associated with injecting equipment sharing (1.64, 1.30-2.07), groin injection (2.03, 1.60-2.56) in the past month, overdosing in the past year (1.90, 1.42-2.53), homelessness in the past year (1.42, 1.14-1.77) and ever having hepatitis C infection (1.64, 1.31-2.06).

CONCLUSION

Crack injection has increased significantly over the past decade in England and Wales. People injecting crack are more likely to engage in behaviours that increase the risk of BBV and SSTI acquisition, such as needle/syringe sharing, groin injection and polydrug use. Harm reduction and drug treatment services should adapt to support the needs of this growing population of people injecting stimulants.

Gender, sexual orientation identity, and initiation of amphetamine injecting among people who inject drugs: Examination of an expanding drug era in Montreal, Canada, 2011-19

BACKGROUND

Amphetamine injection is expanding in North America and has been associated with male homosexuality among people who inject drugs (PWID). Applying subcultural evolution theory, we examined overall and gender-stratified trends in amphetamine injection and assessed sexual orientation as a gender-specific predictor of initiation among PWID in Montreal, Canada.

METHODS

Data were from HEPCO, an open prospective cohort of PWID. Gender and sexual orientation were self-identified at enrolment. Interviewer-administered questionnaires at three-monthly (HCV RNA-negative participants) or yearly (RNA-positive) intervals captured past three-month amphetamine injection and covariates. Annual prevalence and linear trends in amphetamine injection were estimated using GEE. Incidence was computed among naïve individuals and hazard ratios for initiation estimated using gender-stratified, time-varying Cox regression models.

RESULTS

803 participants contributed 8096 observations between March 2011 and December 2019. Annual prevalence of amphetamine injecting increased from 3.25% [95%CI: 2.06-4.43%] to 12.7% [9.50-16.0] (trend p<0.001). Bivariate Cox regression models suggested similar and divergent predictors of initiation by gender. Incidence was 3.27 per 100 person-years [95%CI: 2.51-4.18] among heterosexual men, 7.18 [3.50-13.2] among gay/bisexual men, 1.93 [0.78-4.02] among heterosexual women and 5.30 [1.69-12.8] among gay/bisexual women. Among men, gay/bisexual identity doubled risk of initiation after adjusting for age, ethnicity, calendar year (aHR 2.16 [1.07-4.36]) and additional covariates (2.56 [1.24-5.30]). Among women, evidence for an association with gay/bisexual identity was inconclusive (aHR 2.63 [0.62-11.2]) and sample size precluded further adjustment CONCLUSIONS: Prevalence of amphetamine injection among PWID increased four-fold from 2011 to 2019, with elevated risk of initiation in gay and bisexual men.

Patterns and motivations of polysubstance use: a rapid review of the qualitative evidence

INTRODUCTION

Polysubstance use-the use of substances at the same time or close in time-is a common practice among people who use drugs. The recent rise in mortality and overdose associated with polysubstance use makes understanding current motivations underlying this pattern critical. The objective of this review was to synthesize current knowledge of the reasons for combining substances in a single defined episode of drug use.

METHODS

We conducted a rapid review of the literature to identify empirical studies describing patterns and/or motivations for polysubstance use. Included studies were published between 2010 and 2021 and identified using MEDLINE, Embase, PsycINFO and Google Scholar.

RESULTS

We included 13 qualitative or mixed-method studies in our analysis. Substances were combined sequentially to alleviate withdrawal symptoms or prolong a state of euphoria ("high"). Simultaneous use was motivated by an intention to counteract or balance the effect(s) of a substance with those of another, enhance a high or reduce overall use, and to mimic the effect of another unavailable or more expensive substance. Self-medication for a pre-existing condition was also the intention behind sequential or simultaneous use.

CONCLUSION

Polysubstance use is often motivated by a desire to improve the experience based on expected effects of combinations. A better understanding of the reasons underlying substance combination are needed to mitigate the impact of the current overdose crisis.

Transition from injecting opioids to smoking fentanyl in San Francisco, California

BACKGROUND

The introduction of illicitly made fentanyl in the United States has slowly replaced heroin. New illicit drugs are often associated with changes in frequency and modes of administration. We assessed changes in injection frequency and smoking fentanyl in the new era of fentanyl availability in San Francisco.

METHODS

We used targeted sampling to recruit 395 people who inject drugs (PWID) into an observational cohort study in San Francisco 2018-2020. We assessed changes in injection frequency, opioid injection frequency and fentanyl smoking frequency in four six-month periods. We also conducted qualitative interviews with PWID asking about motivations for injecting and smoking opioids.

RESULTS

The median number of past-month injections steadily decreased by semi-annual calendar year from 92 injections in July to December 2018 to 17 injections in January to June 2020. The rate of opioid injections reduced by half (Adjusted Incidence Rate Ratio = 0.41; 95 % Confidence Interval = 0.25, 0.70; p < 0.01). The number of days smoking fentanyl was associated with fewer number of injections (X2(2) = 11.0; p < 0.01). Qualitative interviews revealed that PWID's motivation for switching from injecting tar heroin to smoking fentanyl was related to difficulties accessing veins. After switching to smoking fentanyl, they noticed many benefits including how the drug felt, improved health, fewer financial constraints, and reduced stigma.

CONCLUSION

Between 2018 and 2020, there was a shift from injecting tar heroin to smoking fentanyl in San Francisco. Reductions in injection of illicit drugs may offer public health benefit if it reduces risk of blood-borne viruses, abscesses and soft-tissue infections, and infective endocarditis.

'Resurgent', 'twin' or 'silent' epidemic? A select data overview and observations on increasing psycho-stimulant use and harms in North America

In the early 2000s, increasing prevalence of psycho-stimulant (e.g., crack/cocaine, methamphetamine) use and related harms, including severe adverse health outcomes, was observed among - mostly marginalized - populations of persons using illicit drugs in North America, underscoring an urgent need for interventions options towards improved prevention and treatment. By about 2010, however, the 'opioid crisis', featuring unprecedented use and public health burden, had accelerated into full force in North America, largely muting attention to the psycho-stimulant issue until recently. Recent surveillance data on drug use and related mortality/morbidity from the present decade has documented a marked resurgence of psycho-stimulant use and harms especially in at-risk populations, commonly in direct combination with opioids, across North America, resulting in a 'twin epidemic' comprised of opioids and psycho-stimulants We briefly review select epidemiological data indicators for these developments from the United States and Canada; in the latter jurisdiction, related evidence has been less prevalent and systematic but corroborating the same trends. Evidently, the (widely ongoing) focus on the 'opioid epidemic' as a 'mono-type' drug problem has become an anachronism that requires urgent and appropriate correction. We then briefly consider existing, evidence-based options for - prevention and treatment - interventions targeting psycho-stimulant use and harms, which are substantially more limited and/or less efficacious than those available for problematic opioid use, while presenting major gaps and challenges. The observed resurgence of psycho-stimulants may, indirectly, relate to recent efforts towards curtailing (medical) opioid availability, thereby accelerating demand and supply for both illicit opioids and psycho-stimulants. The presently unfolding 'twin epidemic' of opioids and psycho-stimulants, combined with limited intervention resources, presents an acute challenge for public health and may crucially undermine actively extensive efforts to reduce opioid-related health harms in North America.

High prevalence of Hepatitis C Virus infection among people who use crack cocaine in an important international drug trafficking route in Central-West Region Brazil

In this study, the prevalence rate, associated risk factors and genetic diversity of hepatitis C virus (HCV) infection were determined among people who use crack from an international drug trafficking route in Central-West, Brazil. Blood samples were collected from 700 users of crack from Campo Grande and two border cities of Mato Grosso do Sul State and tested for HCV infection using serological and molecular testing methodologies. Anti-HCV was detected in 31/700 (4.5%, 95% CI: 2.9-6.0%) and HCV RNA in 26/31 (83.9%) of anti-HCV positive samples. Phylogenetic analysis of three HCV sub-genomic regions (5'UTR, NS5B and HVR-1) revealed the circulation of 1a (73.9%), 1b (8.7%) and 3a (17.4%) genotypes. Next-generation sequencing and phylogenetic analysis of intra-host viral populations of HCV HVR-1 showed a significant variation in intra-host genetic diversity among infected individuals, with 58.8% composed of more than one sub-population. Bayesian analysis estimated that the most recent common HCV ancestor for strains identified here was introduced to this region after 1975 following expansion of intravenous drug use in Brazil. Multivariate analyses showed that only 'ever having injected drugs' was independently associated with HCV infection. These results indicate an increasing spread of multiple HCV strains requiring public health intervention, such as harm reduction, testing services and treatment among crack users in this important border region of Central Brazil.

Examining the Association Between Psychiatric Disorders and Cocaine Binges: Results From the COSMO Study

OBJECTIVES

Although cocaine binges and mental health problems have both been identified as significant risk factors for different health hazards, little is known about the relationship between mental health and cocaine binging. Hence, the aim of this study is to examine the association between psychiatric disorders and cocaine binge.

METHODS

Participants were part of a prospective cohort study of individuals who either smoke or inject cocaine. The dependent variable, namely a cocaine binge within the past month, was defined as the repetitive use of large quantities of cocaine until the individual was unable to access more of the drug or was physically unable to keep using. Psychiatric disorders were assessed using the Composite International Diagnostic Interview and the Diagnostic Interview Schedule questionnaires. Logistic regression models were performed to examine the association between cocaine binging and psychiatric disorders, adjusting for potential confounders.

RESULTS

Of the 492 participants, 24.4% reported at least 1 cocaine binging episode during the prior month. Among the study population, 48.0% met the criteria for antisocial personality disorder (ASPD), 45.5% for anxiety disorders, and 28.2% for mood disorders. Participants with ASPD were more likely to binge (adjusted odds ratio 1.73, 95% confidence interval 1.10-2.73), whereas those with a mood disorder were not. The association between anxiety disorders and cocaine binging was significant only in univariate analyses.

CONCLUSION

ASPD increased the odds of reporting cocaine binge in our study population. These results highlight the need for a better understanding of the specific dimensions of ASPD that contribute to the increased risk of unsafe drug use behaviors.

"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.

High hepatitis C incidence in relation to prescription opioid injection and poly-drug use: Assessing barriers to hepatitis C prevention

BACKGROUND

Prescription opioid (PO) injection and poly-drug use have been associated with hepatitis C virus (HCV) infection among people who inject drugs (PWID). Poly-drug use is often a barrier to key HCV preventive programmes including opioid agonist treatment. The contribution of specific drug combinations to high HCV incidence in poly-drug users has not been assessed previously. Addressing this knowledge gap could enhance HCV treatment and prevention efforts. We examined the association between specific drugs and number of drugs used in addition to injected POs, and HCV seroconversion.

METHODS

PWID participating in a cohort study in Montréal (HEPCO), HCV-seronegative at baseline and followed between 2004 and 2013, were included. Data were collected by interview-administered questionnaires. Blood samples were tested for HCV new infections at each 3-6 month follow-up visit. Time-varying Cox regression models were utilized.

RESULTS

Of 356 participants (81.5% males; mean age: 34.7 years), 123 (34.6%) reported injected POs in the past month at baseline. In univariate analyses, recent use of the following drugs was associated with HCV seroconversion: injected POs, injected cocaine, injected heroin, non-injected tranquilisers, and smoked crack/cocaine. The relative excess risk of HCV seroconversion due to interaction (RER1_HR) was the highest for co-use of injected POs with the following substances: injected cocaine (RER1_HR=3.44), smoked crack/cocaine (RER1_HR=1.27), and non-injected tranquilisers (RER1_HR=0.8). In addition, a significant linear trend (p<0.001) towards higher risk was observed with increasing the number of these three drugs used in combination with injected POs.

CONCLUSION

Specific drugs and number of drugs used in addition to injected POs play a modulating role in the risk of HCV primary infection. Poly-drug use among people who inject POs has to be addressed in order to improve harm reduction programmes and reduce HCV transmission in this high-risk population.

Drug use generations and patterns of injection drug use: Birth cohort differences among people who inject drugs in Los Angeles and San Francisco, California

OBJECTIVES

A robust literature documents generational trends in drug use. We examined the implications of changing national drug use patterns on drug injection histories of diverse people who inject drugs (PWID).

METHODS

Drug use histories were collected from 776 active PWID in 2011-13. Using descriptive statistics, we examine drug use initiation by year and birth cohort (BC) differences in drug first injected. A multivariate linear regression model of time to injection initiation ([TTII] (year of first injection minus year of first illicit drug use) was developed to explore BC differences.

RESULTS

The first drug injected by BC changed in tandem with national drug use trends with heroin declining from 77% for the pre-1960's BC to 58% for the 1960's BC before increasing to 71% for the 1990's BC. Multivariate linear regression modeling found that shorter TTII was associated with the 1980's/1990's BC (-3.50 years; 95% Confidence Interval [CI]=-0.79, -6.21) as compared to the 1970's BC. Longer TTII was associated with being female (1.65 years; 95% CI=0.40, 2.90), African American (1.69 years; 95% CI=0.43, 2.95), any substance use treatment prior to injection (4.22 years; 95% CI=2.65, 5.79), and prior non-injection use of drug that was first injected (3.29 years; 95% CI=2.19, 4.40).

CONCLUSION

National drug trends appear to influence injection drug use patterns. The prescription opiate drug era is associated with shorter TTII. Culturally competent, demographically and generationally-targeted prevention strategies to combat transitions to drug injection are needed to prevent or shorten upstream increases in risky drug use practices on a national level.

Examining the link between cocaine binging and individual, social and behavioral factors among street-based cocaine users

AIMS

To estimate the prevalence of cocaine binging and examine associated factors, to characterize binge episodes and to study the relationship between cocaine binging and HIV and HCV risk behaviors among street-based cocaine users.

METHODS

A prospective cohort study was conducted in Montréal, Canada. Interviewer-administered questionnaire were carried out at 3-month intervals. Cocaine binging was defined as using large quantities of cocaine, without stopping, over a limited period of time, until resources run out or until being physically incapable of consuming. Generalized Estimation Equations (GEE) analyses were used. Covariates considered included demographic, behavioral, mental health and social risk factors.

FINDINGS

In total, 605 participants were recruited. Prevalence of cocaine binging over the month prior to recruitment was 24.5%. Correlates of cocaine binging were older age (AOR 1.46), homelessness (AOR 1.44), criminal/marginal income strategies (AOR 1.61), high psychological distress (AOR 1.31), high cocaine dependence (AOR 3.71), drug overdoses (AOR 1.56) and smoking as the main route of cocaine administration (AOR 1.38). Additional GEE analyses showed that cocaine binging was significantly associated with the sharing of drug paraphernalia (AOR 1.35) and sexual relations under the influence of cocaine (AOR 1.21).

CONCLUSION

Cocaine binging is frequent among street-based cocaine users and is associated with markers of vulnerability. It is also associated with increased odds of both sexual and drug use risk behaviors. Interventions need to be tailored in order to help cocaine bingers develop personal strategies that could prevent binging. Harm reduction programs should help cocaine bingers adequately assess their drug equipment needs.

Revisão sistemática da literatura sobre crack: análise do seu uso prejudicial nas dimensões individual e contextual

RESUMO Este artigo visa investigar como se conformam, no Brasil e internacionalmente, as abordagens ao uso prejudicial do crack e outras drogas. Foi realizada uma revisão crítica da literatura acerca do padrão de consumo do crack e os fatores a ele relacionados com busca sistemática em bases eletrônicas no período de 2010 a 2016. Foram analisados 37 artigos por autor, ano, país do estudo, metodologia; padrão de consumo de crack e fatores individuais e contextuais relativos a esse uso. Conclui-se que a abordagem ao uso de drogas deve estar focada na perspectiva da redução de danos, na promoção da autonomia e dos direitos humanos, e não na utopia de eliminação do consumo e da produção de drogas.

Prescription Opioid Injection Among HIV-Positive People Who Inject Drugs in a Canadian Setting

Prescription opioids (POs) are commonly prescribed to patients living with HIV/AIDS, while the illicit use of POs remains a major public health concern throughout Canada and the United States. We sought to identify the prevalence and correlates of PO injection among HIV-positive people who inject drugs (PWID) in Vancouver, Canada, where HIV/AIDS treatment and care is offered at no cost. We examined data from 634 individuals from an ongoing prospective cohort of HIV-positive PWID. Between December 2005 and November 2013, the median prevalence of recent PO injection was 24.2 % [interquartile range (IQR): 21.5-25.8 %]. In a multivariable generalized estimating equation model, Caucasian ethnicity, heroin injection, and drug dealing were positively associated with PO injection, while older age and methadone maintenance treatment were negatively associated with PO injection (all p < 0.05). Engagement on antiretroviral therapy was inversely associated with PO injection in a bivariable analysis, but did not remain significant after adjusting for heroin injection. These findings describe a particularly vulnerable sub-group of PWID who may benefit from targeted efforts to both minimize drug-related risk behaviors and support HIV/AIDS treatment.

Epidemiology of Injection Drug Use: New Trends and Prominent Issues

After more than 30 years of research, numerous studies have shown that injection drug use is associated with a wide range of adverse health outcomes such as drug overdoses, drug-related suicidal behaviours, comorbid psychiatric disorders, bloodborne pathogens and other infectious diseases, and traumas. This review explores new trends and prominent issues associated with injection drug use. The dynamic nature of injection drug use is underlined by examining its recent trends and changing patterns in Canada and other "high-income countries." Three research topics that could further contribute to the development of comprehensive prevention and intervention strategies aimed at people who inject drugs are also discussed: risk behaviours associated with the injection of prescription opioids, binge injection drug use, and mental health problems as determinants of injection risk behaviours.

Powder and crack cocaine use among opioid users: is all cocaine the same?

OBJECTIVES

Problematic cocaine use is highly prevalent and is a significant public health concern. However, few investigations have distinguished between the 2 formulations of cocaine (ie, powder and crack cocaine) when examining the characteristics of cocaine use. Moreover, research has yet to assess the patterns of powder and crack cocaine use among opioid users, a clinical population in which problematic cocaine use is increasingly common. Using a within-subjects design, this study examined whether opioid users reported different patterns and features of powder and crack cocaine use, along with distinct trajectories and consequences of use.

METHODS

Seventy-three clients enrolled in a low-threshold methadone maintenance treatment were interviewed regarding their lifetime use of powder and crack cocaine.

RESULTS

Compared with crack cocaine, initiation and peak use of powder cocaine occurred at a significantly younger age. In relation to recent cocaine use, participants were significantly more likely to report using crack cocaine than using powder cocaine. Differences in routes of administration, polysubstance use, and criminal activity associated with cocaine use were also found between the 2 forms of cocaine.

CONCLUSIONS

Results suggest that it may not be appropriate to consider powder and crack cocaine as diagnostically and clinically equivalent. As such, researchers may wish to distinguish explicitly between powder and crack cocaine when assessing the characteristics and patterns of cocaine use among substance users and treat these 2 forms of cocaine separately in analyses.

Illicit drug use and harms, and related interventions and policy in Canada: A narrative review of select key indicators and developments since 2000

BACKGROUND

By the year 2000, Canada faced high levels of illicit drug use and related harms. Simultaneously, a fundamental tension had raisen between continuing a mainly repression-based versus shifting to a more health-oriented drug policy approach. Despite a wealth of new data and numerous individual studies that have emerged since then, no comprehensive review of key indicators and developments of illicit drug use/harm epidemiology, interventions and law/policy exist; this paper seeks to fill this gap.

METHODS

We searched and reviewed journal publications, as well as key reports, government publications, surveys, etc. reporting on data and information since 2000. Relevant data were selected and extracted for review inclusion, and subsequently grouped and narratively summarized in major topical sub-theme categories.

RESULTS

Cannabis use has remained the principal form of illicit drug use; prescription opioid misuse has arisen as a new and extensive phenomenon. While new drug-related blood-borne-virus transmissions declined, overdose deaths increased in recent years. Acceptance and proliferation of - mainly local/community-based - health measures (e.g., needle exchange, crack paraphernalia or naloxone distribution) aiming at high-risk drug users has evolved, though reach and access limitations have persisted; Vancouver's 'supervised injection site' has attracted continued attention yet remains un-replicated elsewhere in Canada. While opioid maintenance treatment utilization increased, access to treatment for key (e.g., infectious disease, psychiatric) co-morbidities among drug users remained limited. Law enforcement continued to principally focus on cannabis and specifically cannabis users. 'Drug treatment courts' were introduced but have shown limited effectiveness; several attempts cannabis control law reform have failed, except for the recent establishment of 'medical cannabis' access provisions.

CONCLUSIONS

While recent federal governments introduced several law and policy measures reinforcing a repression approach to illicit drug use, lower-level jurisdictions (e.g., provincial/municipal levels) and non-governmental organizations increasingly promoted social- and health-oriented intervention frameworks and interventions, therefore creating an increasingly bifurcated - and inherently contradictory - drug policy landscape and reality in Canada.

Exploration of a crack use setting and its impact on drug users' risky drug use and sexual behaviors: the case of piaules in a Montréal neighborhood

From July 2011, a one-year study based on ethnographic methodology was carried out in "crack houses" in the neighborhood of Hochelaga-Maisonneuve in Montréal, Canada. The study aimed to explore the operational style of a specific indoor drug use setting and its impact on users' risky sexual and drug use behaviors in a context of drug market change. A thematic analysis of observational and interview notes was conducted. This study stresses the importance to examine the role of environmental factors in relation to crack smoking's health-related risks and to complement individual-based interventions with structural strategies. The study's limitations are noted.

Estimating the size of the population of persons who inject drugs in the island of Montréal, Canada, using a six-source capture-recapture model

BACKGROUND

To plan and implement services to persons who inject drugs (PWID), knowing their number is essential. For the island of Montréal, Canada, the only estimate, of 11,700 PWID, was obtained in 1996 through a capture-recapture method. Thirteen years later, this study was undertaken to produce a new estimate.

METHODS

PWID were defined as individuals aged 14-65 years, having injected recently and living on the island of Montréal. The study period was 07/01/2009 to 06/30/2010. An estimate was produced using a six-source capture-recapture log-linear regression method. The data sources were two epidemiological studies and four drug dependence treatment centres. Model selection was conducted in two steps, the first focusing on interactions between sources and the second, on age group and gender as covariates and as modulators of interactions.

RESULTS

A total of 1480 PWID were identified in the six capture sources. They corresponded to 1132 different individuals. Based on the best-fitting model, which included age group and sex as covariates and six two-source interactions (some modulated by age), the estimated population was 3910 PWID (95% confidence intervals (CI): 3180-4900) which represents a prevalence of 2.8 (95% CI: 2.3-3.5) PWID per 1000 persons aged 14-65 years.

CONCLUSIONS

The 2009-2010 estimate represents a two-third reduction compared to the one for 1996. The multisource capture-recapture method is useful to produce estimates of the size of the PWID population. It is of particular interest when conducted at regular intervals thus allowing for close monitoring of the injection phenomenon.

Correlates of drug use cessation among participants in the Canadian HIV-HCV Co-infection Cohort

BACKGROUND

Ongoing drug use remains a barrier to HIV and HCV treatment. We examined the occurrence and correlates of drug use cessation among HIV-HCV co-infected drug users participating in HIV care.

METHODS

Participants from the Canadian Co-infection Cohort reporting drug use (injecting drugs and/or smoking crack) with at least two follow-up visits were included (n=521 (43%), 1832 visits). Socio-demographics, behavioural, and health information were collected at each six-month visit. Associations with cessation (no drug use since last visit) were examined using non-linear mixed effects logistic regression models with random intercepts.

RESULTS

During follow-up, 361 (69%) participants ceased using drugs. Having a fixed address (aOR [adjusted odds ratio] 1.73, CI [95% confidence interval] 1.02-2.96) and smoking crack without injecting drugs (aOR 3.10, CI 2.05-4.71) were positively associated. Living alone (aOR 0.47, CI 0.35-0.63), current tobacco use (aOR 0.41, CI 0.26-0.64), hazardous alcohol drinking (aOR 0.67, CI 0.49-0.91), snorting drugs (aOR 0.52, CI 0.37-0.74), having a greater exposure to addiction programmes (aOR 0.88, CI 0.81-0.94), having been recruited in Quebec or Nova Scotia (aOR 0.41, CI 0.25-0.66), and British Columbia or Alberta (aOR 0.51, CI 0.32-0.82) were negatively associated. Various socio-demographic (age, education) and health-related (HIV duration, care adherence) factors were not associated.

CONCLUSION

Drug use cessation among HIV-HCV co-infected persons is relatively common in this cohort. Stable housing and supportive living situations seem to be important facilitators for drug use cessation in this population. Greater efforts should be made to retain patients in addiction treatment programmes.

Prevalence and temporal trends of crack injection among injection drug users in eastern central Canada

BACKGROUND

Little is known about crack injection and its temporal trends in North America. This article describes the extent of crack injection and examines temporal trends among injection drug users (IDUs) recruited from 2003 to 2010 in the SurvUDI network.

METHODS

IDUs who injected recently (past 6 months) were recruited in harm reduction and health programs in eastern central Canada. Trend analyses were performed using generalized estimating equations. Some IDUs participated multiple times; first interview was retained for the descriptive analyses, while first interview per year was retained for the trend analyses.

RESULTS

Of the 4088 IDUs recruited, 15.2% (621) reported crack injection; large variations across sites were noted (range: 0.3-39.5%). Trend analyses were limited to Ottawa (449 crack injectors) and Montréal (121). For Ottawa, a significant decline was observed, from 48.3% to 36.9%, with a prevalence ratio (PR) of 0.97 per year (95% CI: 0.94-0.99). For Montréal, a significant rise was observed, from 6.0% to 18.4%, with a PR of 1.29 per year (95% CI: 1.19-1.40).

CONCLUSIONS

Strong variations in crack injection exist throughout the SurvUDI network, and reversed temporal trends have been observed in Ottawa and Montréal. These data will be useful to local harm reduction programs to evaluate the need to distribute items required by crack injectors and to develop prevention messages.

A cost-benefit/cost-effectiveness analysis of proposed supervised injection facilities in Montreal, Canada

Background

This paper will determine whether expanding Insite (North America’s first and only supervised injection facility) to more locations in Canada such as Montreal, cost less than the health care consequences of not having such expanded programs for injection drug users.

Methods

By analyzing secondary data gathered in 2012, this paper relies on mathematical models to estimate the number of new HIV and Hepatitis C (HCV) infections prevented as a result of additional SIF locations in Montreal.

Results

With very conservative estimates, it is predicted that the addition of each supervised injection facility (up-to a maximum of three) in Montreal will on average prevent 11 cases of HIV and 65 cases of HCV each year. As a result, there is a net cost saving of CDN$0.686 million (HIV) and CDN$0.8 million (HCV) for each additional supervised injection site each year. This translates into a net average benefit-cost ratio of 1.21: 1 for both HIV and HCV.

Conclusions

Funding supervised injection facilities in Montreal appears to be an efficient and effective use of financial resources in the public health domain.

Interdisciplinary mixed methods research with structurally vulnerable populations: case studies of injection drug users in San Francisco

Research with injection drug users (IDUs) benefits from interdisciplinary theoretical and methodological innovation because drug use is illegal, socially sanctioned and often hidden. Despite the increasing visibility of interdisciplinary, mixed methods research projects with IDUs, qualitative components are often subordinated to quantitative approaches and page restrictions in top addiction journals limit detailed reports of complex data collection and analysis logistics, thus minimizing the fuller scientific potential of genuine mixed methods. We present the methodological logistics and conceptual approaches of four mixed-methods research projects that our interdisciplinary team conducted in San Francisco with IDUs over the past two decades. These projects include combinations of participant-observation ethnography, in-depth qualitative interviewing, epidemiological surveys, photo-documentation, and geographic mapping. We adapted Greene et al.'s framework for combining methods in a single research project through: data triangulation, methodological complementarity, methodological initiation, and methodological expansion. We argue that: (1) flexible and self-reflexive methodological procedures allowed us to seize strategic opportunities to document unexpected and sometimes contradictory findings as they emerged to generate new research questions, (2) iteratively mixing methods increased the scope, reliability, and generalizability of our data, and (3) interdisciplinary collaboration contributed to a scientific "value added" that allowed for more robust theoretical and practical findings about drug use and risk-taking.

Injection of drug residue as a potential risk factor for HCV acquisition among Montréal young injection drug users

BACKGROUND

Preparing drugs or medications for injection may leave residues in containers and filters used by injection drug users (IDUs). Little is known about the specific practice of injecting someone else's drug residue as a possible route of HCV transmission.

METHODS

A prospective cohort study of street youth aged 14-23 years old was carried out between July 2001 and December 2005. For this analysis, youth who injected in the six months prior to interview were selected if they were HCV-negative and had completed at least one follow-up visit. Semi-annual visits involved completing an interviewer-administered questionnaire and providing a blood sample for HCV antibody testing. "Sharing behaviors" (any injection preparation behavior that could entail IDUs using injection equipment used by others) including injecting someone else's drug residue were assessed at each interview. Predictors of HCV seroconversion were identified using Cox proportional hazards regression analyses. Two multivariate models were built, one considering sharing behaviors only, and one with cocaine injection forced into it.

RESULTS

Of the 175 participants, 60% were male and their mean age was 20.7years old. In both models, residue injection was a predictor of HCV incidence, although with marginal statistical significance. The adjusted hazard ratio estimates were (2.15; 95% CI 0.99-4.67) and (2.11; 95% CI 0.97-4.62) respectively.

CONCLUSION

This epidemiological study underscores the role injection of drug residue may play in HCV transmission among IDUs. In the current context of the worldwide HCV epidemics, this question deserves further investigation.

The rising prevalence of prescription opioid injection and its association with hepatitis C incidence among street-drug users

AIMS

  To examine trends in prescription opioid (PO) injection and to assess its association with hepatitis C virus (HCV) seroconversion among injection drug users (IDUs).

DESIGN

  Prospective cohort study.

SETTING

  Montreal, Canada.

PARTICIPANTS

  HCV-negative IDUs at baseline, reporting injection in the past month.

MEASUREMENTS

  Semi-annual visits included HCV antibody testing and an interview-administered questionnaire assessing risk behaviours. HCV incidence rate was calculated using the person-time method. Time-updated Cox regression models were conducted to examine predictors of HCV incidence.

FINDINGS

  The proportion of IDUs reporting PO injection increased from 21% to 75% between 2004 and 2009 (P < 0.001). Of the 246 participants (81.6% male; mean age 34.5 years; mean follow-up time 23 months), 83 seroconverted to HCV [incidence rate: 17.9 per 100 person-years; 95% confidence interval (CI) 14.3, 22.1]. Compared to non-PO injectors, PO injectors were more likely to become infected [adjusted hazard ratio (AHR): 1.87; 95%CI:1.16, 3.03]. An effect modification was also found: PO injectors who did not inject heroin were more likely to become infected (AHR: 2.88; 95%CI: 1.52, 5.45) whereas no association was found for participants using both drugs (AHR: 1.19; 95% CI: 0.61, 2.30). Other independent predictors of HCV incidence were: cocaine injection, recent incarceration and >30 injections per month.

CONCLUSIONS

  Prescription opioid injectors who do not inject heroin are at greater risk for HCV seroconversion than are those injecting both heroin and prescription opioids. Important differences in age, behaviour and social context suggest a need for targeted outreach strategies to this population.