Impact de la consommation de cannabis chez les utilisateurs de drogues intraveineuses

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Cannabis use correlates of syringe sharing among injection drug users

Ce manuscrit est une pré-publication d'un article paru dans The American Journal on Addictions 2010; 19(3): 231-237 url: http://onlinelibrary.wiley.com/doi/10.1111/ajad.2010.19.issue-3/issuetocIRSC et FRSQ - Réseau SIDA et maladies infectieuse

Neurobiologie de la toxicomanie : avancées récentes et nouvelles stratégies d’intervention

Pendant longtemps, la toxicomanie a été associée sur le plan neurobiologique à la modulation à court terme de différents systèmes de neurotransmission. Les stratégies de traitement ciblaient conséquemment les récepteurs auxquels se lie directement la substance étant source d’abus. Ces approches ont contribué à améliorer le soulagement des symptômes d’intoxication et de sevrage, tout en favorisant l’accès à des services psychosociaux adaptés. Toutefois, les données soulignent, chez certains sous-groupes d’individus, l’efficacité parfois mitigée de ces interventions visant à diminuer de façon soutenue la consommation et les symptômes associés à la toxicomanie, particulièrement le craving. Les avancées récentes en neurosciences ont permis de mieux comprendre les mécanismes neurobiologiques expliquant la vulnérabilité à la rechute. D’une conception essentiellement dopaminergique et striatale, les théories biologiques de la toxicomanie intègrent maintenant la contribution des systèmes glutamatergique, opioïde et endocannabinoïde, de même que l’interaction entre ces différentes composantes au sein des structures corticales et sous-corticales. L’intérêt semble avoir migré des phénomènes neurobiologiques à court terme vers la modulation prolongée du fonctionnement des structures en jeu dans la toxicomanie. Ce changement de paradigmes a mené à l’émergence de plusieurs stratégies thérapeutiques visant à diminuer les risques de rechute en modulant de façon plus spécifique les circuits neuronaux dont le fonctionnement est altéré par la prise chronique de substances. Les systèmes endocannabinoïde et glutamatergique, notamment, apparaissent comme une cible de choix pour le traitement du craving et la prévention de la rechute. Le présent article a pour objectif de résumer certains des plus récents courants en matière de conceptualisation neurobiologique de la toxicomanie de même que les nouvelles pistes de traitement en découlant.For years, the neurobiology of drug addiction was characterized by the short-term modulation of different neurotransmission systems, therapeutic strategies directly targeting the receptors that are bound by substances. These approaches have helped to improve the treatment of drug intoxication and withdrawal, while promoting access to a broad array of psychosocial services. However, the data highlight the mixed effectiveness of these interventions to induce a sustained decrease in consumption and other symptoms of addiction, especially craving, among subgroups of individuals. Recent advances in neuroscience have led to a growing understanding of the neurobiological mechanisms underlying the vulnerability to relapse and other behaviors associated with addiction. The primarily dopaminergic and striatal hypothesis of these phenomena has been replaced by a theory incorporating the contribution of the glutamatergic, endocannabinoid and opioid systems, as well as the interaction between these various components within cortical and sub-cortical structures. The focus has moved from the short-term neurobiological changes to the long-lasting modulation of the structures involved in addiction. This paradigm shift led to the emergence of several therapeutic strategies that aim at reducing the risk of relapse by modulating specific neural circuits whose functions are altered by chronic substance use. The endocannabinoid and glutamate systems, in particular, are promising targets for the treatment of craving and relapse. This article aims to summarize some of the latest trends in the neurobiology of addiction as well as new avenues of treatment.Durante mucho tiempo la toxicomanía estuvo asociada en el plano neurobiológico con la modulación a corto plazo de diferentes sistemas de neurotransmisión. Las estrategias de tratamiento apuntaban, por consiguiente, a los receptores que se vinculan directamente con la sustancia que es el origen del abuso. Estos enfoques contribuyeron a mejorar el alivio de los síntomas de intoxicación y abstinencia, favoreciendo al mismo tiempo el acceso a servicios psicosociales adaptados. Sin embargo, en ciertos grupos de individuos, los datos destacan la eficacia a veces mitigada de estas intervenciones destinadas a disminuir de manera continua el consumo y los síntomas relacionados con la toxicomanía, particularmente el craving. Los recientes progresos de la neurociencia permitieron comprender mejor los mecanismos neurobiológicos que explican la vulnerabilidad ante la recaída. De concepción esencialmente dopaminérgica y estratial, las teorías biológicas de la toxicomanía integran ahora la contribución de los sistemas glutamatérgico, opiáceo y endocanabinoide, así como la interacción entre estos diferentes componentes dentro de las estructuras corticales y subcorticales. El interés parece haberse desplazado de los fenómenos neurobiológicos de corto plazo hacia la modulación prolongada del funcionamiento de las estructuras que están en juego en la toxicomanía. Este cambio de paradigmas condujo al surgimiento de numerosas estratégicas terapéuticas destinadas a disminuir los riesgos de recaída al modular más específicamente los circuitos neuronales cuyo funcionamiento está alterado por el consumo crónico de drogas. Los sistemas endocanabinoide y glutamatérgico, principalmente, aparecen como un objetivo a privilegiar para el tratamiento del craving y la prevención de la recaída. El presente artículo está destinado a resumir algunas de las más recientes corrientes en materia de conceptualización neurobiológica de la toxicomanía y las nuevas vías de tratamiento a las que dichas corrientes dan origen

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

Ce manuscrit est une pré-publication d'un article paru dans Addiction 2012; 107(7): 1318-1327 url: http://www.addictionjournal.org/IRSC et FRSQ - Réseau SIDA et maladies infectieuse

A systematic review of technology-based psychotherapeutic interventions for decreasing cannabis use in patients with psychosis

Persistent use of cannabis in persons with psychosis is associated with poor symptomatic and functional outcomes and increased healthcare costs. Face-to-face psychological interventions (e.g., Cognitive Behavioral Therapy- [CBT], Motivation Enhancement Therapy- [MET]) are widely used in treating problematic cannabis use. We aimed to comprehensively review the efficacy of technologybased psychological interventions (TBPIs) in decreasing cannabis use, the design of TBPIs, and TBPIrelated preferences in individuals with psychosis. For the systematic review, we searched six major databases from their inception to November 27, 2019. We included empirical articles of quantitative and qualitative methodologies related to TBPIs in individuals with psychosis and cannabis misuse and used narrative synthesis to report results. Only eight articles were found showing that technology-based motivational and psycho-education interventions and cognitive enhancement therapy were minimally efficient in achieving cannabis abstinence or decreasing frequency of use. Qualitative exploratory methods and participatory action research were used to elicit patient and clinician preferences and TBPIs were tailored accordingly to improve cannabis use related outcomes. Research on TBPIs in individuals with psychosis and cannabis misuse is in its early phases. A significant research effort is needed for the development of adapted interventions of CUD to capitalize on the potential of webbased applications

Improving the self-efficacy, knowledge, and attitude of nurses regarding concurrent disorder care : results from a prospective cohort study of an interprofessional, videoconference-based programme using the ECHO model

Several challenges have been identified for patients with concurrent disorders to access adequate services and for nurses to care for them. These challenges contribute to a pressing need for continuing educational interventions, particularly within the mental health nursing workforce. To address this issue, an innovative interprofessional videoconferencing programme based on the ECHO model (Extension for Community Healthcare Outcomes) was implemented in Quebec, Canada to support and build capacity among healthcare professionals for CD management. The aim of this prospective cohort study was to examine nurses’ self-efficacy, knowledge, and attitude scores over a 12-month period. All nurses who registered in the programme between 2018 and 2020 were invited to participate in the study (N = 65). The data were collected online using a self-administered survey at baseline, after 6 months, and then 12 months following entry-to-programme. Twenty-eight nurses participated in the study (96.4% women), with a mean age of 39.1 (SD = 6.2). Compared to other professions (n = 146/174), the group of nurses also showed significant improvements in their knowledge and attitude scores, with respective effect sizes of 0.72 and 0.44 at 6 months, and 0.94 and 0.59 at 12 months. However, significant changes in self-efficacy were only found at the 12-month follow-up (P = 0.0213), among the nurses who attended more than 25% of the 20-session curriculum. ECHO is a promising intervention to improve the accessibility of evidence-based practice and to support nurses in suitably managing concurrent disorders. Further research is needed to establish the effectiveness of this educational intervention on clinical nursing practice and patient outcomes

Associations of substance use patterns with attempted suicide among persons who inject drugs: Can distinct use patterns play a role?

Background: While the elevated risk of suicide attempt among persons who inject drugs (PWID) is well documented, whether use of different substances is associated with varying degrees of risk remains unclear. We sought to examine the associations between substance use patterns and attempted suicide in a prospective cohort of PWID in Montreal, Canada. Methods: Between 2004 and 2011, participants completed an interviewer-administered questionnaire eliciting information on socio-demographic, substance use patterns, related behaviors, and mental health markers. Generalized estimating equations were used to model the relationship between self-reported use of six common substances (cocaine, amphetamine, opioids, sedative-hypnotics, cannabis and alcohol), associated patterns of use (chronic, occasional and none), and a recent (past six-month) suicide attempt. Results: At baseline, of 1,240 participants (median age: 39.1, 83.7% male), 71 (5.7%) reported a recent suicide attempt. Among 5,621 observations collected during follow-up, 221 attempts were reported by 143 (11.5%) participants. In multivariate analyses adjusting for socio-demographic and psychosocial stressors, among primary drugs of abuse, chronic [Adjusted Odds Ratio (AOR): 1.97] and occasional (AOR: 1.92) cocaine use, and chronic amphetamine use (AOR: 1.96) were independently associated with attempted suicide. Among co-used substances, chronic sedative-hypnotic use was independently associated with an attempt (AOR: 2.29). No statistically significant association was found for the remaining substances. Conclusion: Among PWID at high risk of attempted suicide, stimulant users appear to constitute a particularly vulnerable sub-group. While the mechanisms underlying these associations remain to be elucidated, findings suggest that stimulant-using PWID should constitute a prime focus of suicide prevention efforts

Portraying persons who inject drugs recently infected with hepatitis C accessing antiviral treatment : a cluster analysis

Objectives. To empirically determine a categorization of people who inject drug (PWIDs) recently infected with hepatitis C virus (HCV), in order to identify profiles most likely associated with early HCV treatment uptake. Methods.The study population was composed of HIV-negative PWIDs with a documented recent HCV infection. Eligibility criteria included being 18 years old or over, and having injected drugs in the previous 6 months preceding the estimated date of HCV exposure. Participant classification was carried out using a TwoStep cluster analysis. Results. FromSeptember 2007 to December 2011, 76 participants were included in the study. 60 participants were eligible for HCV treatment. Twenty-one participants initiated HCV treatment.The cluster analysis yielded 4 classes: class 1: Lukewarm health seekers dismissing HCV treatment offer; class 2: multisubstance users willing to shake off the hell; class 3: PWIDs unlinked to health service use; class 4: health seeker PWIDs willing to reverse the fate. Conclusion. Profiles generated by our analysis suggest that prior health care utilization, a key element for treatment uptake, differs between older and younger PWIDs. Such profiles could inform the development of targeted strategies to improve health outcomes and reduce HCV infection among PWIDs

Visits to primary care physicians among persons who inject drugs at high risk of hepatitis C virus infection: room for improvement

The role of primary care physicians (PCP) in hepatitis C virus (HCV) prevention is increasingly emphasized. Yet, little is known about the patterns of contacts with PCP among persons who inject drugs (PWID). We sought to assess the 6-month prevalence of PCP visiting among PWID at risk of HCV infection and to explore the associated factors. Baseline data were collected from HCV-seronegative PWID recruited in HEPCO, an observational Hepatitis Cohort study (2004-2011) in Montreal, Canada. An interviewer-administered questionnaire elicited information on socio-demographic factors, drug use patterns and healthcare services utilization. Blood samples were tested for HCV antibodies. Using the Gelberg-Andersen Behavioral Model, hierarchical logistic regression analyses were conducted to identify predisposing, need and enabling factors associated with PCP visiting. Of the 349 participants (mean age = 34; 80.8% male), 32.1% reported visiting a PCP. In the multivariate model, among predisposing factors, male gender [adjusted odds ratio (AOR) = 0.45 (0.25-0.83)], chronic homelessness [AOR = 0.08 (0.01-0.67)], cocaine injection [AOR = 0.46 (0.28-0.76)] and reporting greater illegal or semi-legal income [AOR = 0.48 (0.27-0.85)] were negatively associated with PCP visits. Markers of need were not associated with the outcome. Among enabling factors, contact with street nurses [AOR = 3.86 (1.49-9.90)] and food banks [AOR = 2.01 (1.20-3.37)] was positively associated with PCP visiting. Only one third of participating PWID reported a recent visit to a PCP. While a host of predisposing factors seems to hamper timely contacts with PCP among high-risk PWID, community-based support services may play an important role in initiating dialogue with primary healthcare services in this population

Discrete time measures versus trajectories of drinking frequency across adolescence as predictors of binge drinking in young adulthood: a longitudinal investigation

OBJECTIVES: We compared discrete time measures with trajectories of adolescent drinking frequency as predictors of sustained binge drinking in young adulthood. DESIGN: Prospective longitudinal study. SETTING: 10 high schools in Montreal, Canada. PARTICIPANTS: 1293 high-school students followed from mean (SD) age 12 (0.6) to 24 (0.7) years. PRIMARY OUTCOME MEASURES: Patterns of drinking frequency (self-reports every 3 months from ages 12 to 17) identified using group-based trajectory modelling. Sustained binge drinking was defined as binging monthly or more often at both ages 20 and 24. ANALYSES: Using logistic regression, sustained binge drinking was regressed on trajectory group membership and on four discrete time measures (frequency of drinking at age 12; frequency of drinking at age 17; age at drinking onset; age at onset of drinking monthly or more often). RESULTS: We identified seven drinking trajectories: late triers (15.2%), decreasers (9.5%), late escalators (10.4%), early slow escalators (16.5%), steady drinkers (14.4%), early rapid escalators (15.8%) and early frequent drinkers (18.2%). Sustained binge drinking was reported by 260 of 787 participants (33.0%) with complete data at both ages 20 and 24. Decreasers did not differ from late triers; all other patterns were associated with higher odds of sustained binge drinking (adjusted ORs: AORs=1.4-17.0). All discrete time measures were associated with sustained binge drinking, notably frequency at age 12 (a bit to try and drinking monthly: (AORs=2.6 (1.7; 3.9) and 2.8 (1.3; 6.1), respectively), age of drinking onset \u3c 13 years (AOR=7.6 (3.0; 24.1)), and any age of onset of drinking monthly or more often (AORs=5.1-8.2). CONCLUSION: Youth at risk of sustained binge drinking as young adults can be identified with indicators of early drinking as early as 7th grade (aged 12-13 years). Identification of easy-to-obtain indicators can facilitate screening and intervention efforts