Warren Michelow

A 'standard joint'? the role of quantity in predicting cannabis-related problems

The ‘standard drink’ concept is widely used as a standardized measure of alcohol consumption. There is no equivalent measure of cannabis consumption, perhaps due to challenges such as varied joint size, tetrahydrocannabinol content, and means of delivery. This study introduces a new measure of cannabis quantity and examines whether it predicts cannabis-related social problems with and without controlling for frequency of use. Cannabis-related problems, measured by the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), were predicted from cannabis use frequency (days in past month) and quantity (one joint = 0.5 g, five bong or pipe hits, 10 puffs), controlling for age and gender. The sample consisted of 665 participants aged 15–67 (mean = 28.2, SD = 11.8) from the British Columbia Alcohol and Other Drug Monitoring Project, High Risk Group Surveys, 2008 to 2009. Cannabis use frequency and quantity were positively associated with cannabis-related problems. Individuals who consumed cannabis daily and consumed more than one joint per day were at the greatest risk of problems. Controlling for frequency, the effect of quantity remained significant for failure to do what is expected due to cannabis use. This study suggests that quantity, above and beyond frequency, is an important predictor of cannabis problems. We discuss the potential usefulness and validity of this new measure in harm reduction.

HIV Incidence and Prevalence Among Aboriginal Peoples in Canada

We examined incidence, prevalence, and correlates of HIV infection in Aboriginal peoples in Canada and found that among most risk groups both Aboriginal and non-Aboriginal participants showed similar levels of HIV prevalence. Aboriginal peoples who use illicit drugs were found to have higher HIV incidence and prevalence when compared to their non-Aboriginal drug-using peers. Aboriginal street youth and female sex workers were also found to have higher HIV prevalence. Among Aboriginal populations, correlates of HIV-positive sero-status include syringe sharing and frequently injecting drugs, as well as geographic and social factors such as living in Vancouver or having a history of non-consensual sex. This study is relevant to Canada and elsewhere, as Indigenous populations are disproportionately represented in the HIV epidemic worldwide.

Community mapping and respondent-driven sampling of gay and bisexual men's communities in Vancouver, Canada

Literature suggests formative research is vital for those using respondent-driven sampling (RDS) to study hidden populations of interest. However, few authors have described in detail how different qualitative methodologies can address the objectives of formative research for understanding the social network properties of the study population, selecting seeds and adapting survey logistics to best fit the population. In this paper we describe the use of community mapping exercises as a tool within focus groups to collect data on social and sexual network characteristics of gay and bisexual men in the metropolitan area of Vancouver, Canada. Three key themes emerged from analysing community maps along with other formative research data: (1) connections between physical spaces and social networks of gay and bisexual men, (2) diversity in communities and (3) substance use linked to formation of sub-communities. We discuss how these themes informed the planning and operations of a longitudinal epidemiological cohort study recruited by RDS. We argue that using community mapping within formative research is a valuable qualitative tool for characterising network structures of a diverse and differentiated population of gay and bisexual men in a highly developed urban setting.

Impact of Statistical Adjustment for Frequency of Venue Attendance in a Venue-based Survey of Men Who Have Sex With Men

Venue sampling is a common sampling method for populations of men who have sex with men (MSM); however, men who visit venues frequently are more likely to be recruited. While statistical adjustment methods are recommended, these have received scant attention in the literature. We developed a novel approach to adjust for frequency of venue attendance (FVA) and assess the impact of associated bias in the ManCount Study, a venue-based survey of MSM conducted in Vancouver, British Columbia, Canada, in 2008-2009 to measure the prevalence of human immunodeficiency virus and other infections and associated behaviors. Sampling weights were determined from an abbreviated list of questions on venue attendance and were used to adjust estimates of prevalence for health and behavioral indicators using a Bayesian, model-based approach. We found little effect of FVA adjustment on biological or sexual behavior indicators (primary outcomes); however, adjustment for FVA did result in differences in the prevalence of demographic indicators, testing behaviors, and a small number of additional variables. While these findings are reassuring and lend credence to unadjusted prevalence estimates from this venue-based survey, adjustment for FVA did shed important insights on MSM subpopulations that were not well represented in the sample.

Sexual identity and drug use harm among high-risk, active substance users

Research shows that sexual minorities are at greater risk for illicit substance use and related harm than their heterosexual counterparts. This study examines a group of active drug users to assess whether sexual identity predicts increased risk of substance use and harm from ecstasy, ketamine, alcohol, marijuana, cocaine and crack. Structured interviews were conducted with participants aged 15 years and older in Vancouver and Victoria, BC, Canada, during 2008–2012. Harm was measured with the World Health Organizations AUDIT and ASSIST tools. Regression analysis controlling for age, gender, education, housing and employment revealed lesbian, gay or bisexual individuals were significantly more likely to have used ecstasy, ketamine and alcohol in the past 30 days compared to heterosexual participants. Inadequate housing increased the likelihood of crack use among both lesbian, gay and bisexuals and heterosexuals, but with considerably higher odds for the lesbian, gay and bisexual group. Lesbian, gay and bisexual participants reported less alcohol harm but greater ecstasy and ketamine harm, the latter two categorised by the ASSIST as amphetamine and hallucinogen harms. Results suggest encouraging harm reduction among sexual minority, high-risk drug users, emphasising ecstasy and ketamine. The impact of stable housing on drug use should also be considered.

Relationship between disclosure of same-sex sexual activity to providers, HIV diagnosis and sexual health services for men who have sex with men in Vancouver, Canada.

OBJECTIVES: Men who have sex with men (MSM) report challenges to accessing appropriate health care. We sought to understand the relationship between disclosure of same-sex sexual activity to a health care practitioner (HCP), sexual behaviour and measures of sexual health care.METHODS: Participants recruited through community venues and events completed a questionnaire and provided a blood sample. This analysis includes only individuals with self-reported HIV negative or unknown serostatus. We compared participants who had disclosed having same-sex partners with those who had not using chi-square, Wilcoxon Rank Sum and Fisher’s exact tests and used logistic regression to examine those variables associated with receiving an HIV test.RESULTS: Participants who had disclosed were more likely to have a higher level of education (p<0.001) and higher income (p<0.001), and to define themselves as “gay” or “queer” (p<0.001). Those who had not disclosed were less likely to report having risky sex (p=0.023) and to have been tested for HIV in the previous two years (adjusted odds ratio 0.23, 95% confidence interval: 0.16–0.34). There was no difference in undiagnosed HIV infection (3.9% versus 2.6%, p=0.34). Individuals who had disclosed were also more likely to have been tested for gonorrhea and syphilis, and more likely to have ever been vaccinated against hepatitis A and hepatitis B (p<0.001 for all).CONCLUSIONS: While generally reporting lower risk behaviour, MSM who did not disclose same-sex sexual activity to their HCP did have undiagnosed HIV infections and were less likely to have been tested or vaccinated. Strategies to improve access to appropriate sexual health care for MSM are needed.RésuméOBJECTIFS: Les hommes ayant des relations sexuelles avec des hommes (HARSAH) disent avoir du mal à accéder à des soins de santé appropriés. Nous avons cherché à comprendre le lien entre la divulgation des relations homosexuelles à un professionnel de la santé (PS), le comportement sexuel et les indicateurs de soins de santé sexuelle.MÉTHODE: Les participants, recrutés dans des lieux et lors d’activités communautaires, ont rempli un questionnaire et fourni un échantillon de sang. Notre analyse n’a porté que sur les sujets ayant déclaré être séronégatifs pour le VIH ou ignorer leur état sérologique. À l’aide du test du khi-carré, du test de Wilcoxon et de la méthode exacte de Fisher, nous avons comparé les participants ayant divulgué le fait d’avoir des relations sexuelles avec d’autres hommes à ceux qui n’avaient pas divulgué leurs relations homosexuelles à un PS; au moyen d’une analyse de régression logistique, nous avons examiné les variables associées au fait d’avoir reçu un test de dépistage du VIH.RÉSULTATS: Les participants ayant divulgué leurs relations homosexuelles étaient plus susceptibles d’avoir un niveau de scolarité plus élevé (p<0,001) et un revenu plus élevé (p<0,001) et de se définir comme étant «gais» ou «queer» (p<0,001). Ceux qui n’avaient pas divulgué leurs pratiques homosexuelles à leur PS étaient moins susceptibles d’avoir eu des relations sexuelles à risque (p=0,023) et d’avoir été dépistés pour le VIH au cours des deux années antérieures (rapport de cotes ajusté de 0,23, intervalle de confiance de 95 %: 0,16–0,34). Il n’y avait pas de différence dans les infections à VIH non diagnostiquées (3,9 % c. 2,6 %, p=0,34). Les sujets ayant divulgué leurs relations homosexuelles étaient aussi plus susceptibles d’avoir été dépistés pour la gonorrhée et la syphilis et d’avoir été vaccinés contre l’hépatite A et l’hépatite B (p<0,001 pour tous).CONCLUSIONS: Bien qu’ils déclarent en général des comportements à moindre risque, les HARSAH qui n’avaient pas divulgué leurs relations homosexuelles à leur PS avaient parfois des infections à VIH non diagnostiquées, et ils étaient moins susceptibles d’avoir été dépistés ou vaccinés. Des stratégies pour améliorer l’accès aux soins de santé sexuelle adaptés aux HARSAH sont nécessaires.

The Canadian Recreational Drug Use Survey: Aims, Methods and First Results

In late 2006, pilot research was initiated in two western Canadian sites (Vancouver and Victoria) to systematically monitor patterns and trends in three specific illicit drug user populations: club and rave party attendees, adolescent street involved injection and non-injection drug users, and adult injection drug users. These sentinel groups were selected because of elevated rates of alcohol and other drug use within these populations and contexts, and the high levels of associated risks and harms. Drawing from international monitoring and surveillance systems, novel research instruments were developed for each population and were administered in face-to-face interviews at each study site. This paper presents an overview of the broad research methodology for the “high risk” monitoring research as well as select findings for the “club drug” sample. The piloted research design yielded high quality data, particularly in relation to recent patterns of drug use behaviour (items on drug use “yesterday” and “last weekend”). The success of these novel items highlights the value of the present study and its relevance for similar studies across the country.

An examination of injection drug use trends in Victoria and Vancouver, BC after the closure of Victoria's only fixed-site needle and syringe programme.

BACKGROUND Needle and syringe programmes (NSPs) have been established as effective harm reduction initiatives to reduce injection drug use (IDU)-related risk behaviours, including sharing needles. On May 31, 2008, Victoria, BCs only fixed site NSP was shut down due to community and political pressure. This study examines and compares IDU trends in Victoria with those in Vancouver, BC, a city which has not experienced any similar disruption of IDU-related public health measures. METHODS Quantitative and qualitative data were collected by interviewer-administered questionnaires conducted with injection drug users (n=579) in Victoria and Vancouver between late 2007 and late 2010. RESULTS Needle sharing increased in Victoria from under 10% in early 2008 to 20% in late 2010, whilst rates remained relatively low in Vancouver. Participants in Victoria were significantly more likely to share needles than participants in Vancouver. Qualitative data collected in Victoria highlight the difficulty participants have experienced obtaining clean needles since the NSP closed. Recent injection of crack cocaine was independently associated with needle sharing. CONCLUSIONS The closure of Victorias fixed site NSP has likely resulted in increased engagement in high-risk behaviours, specifically needle sharing. Our findings highlight the contribution of NSPs as an essential public health measure.

HIV testing behaviour and use of risk reduction strategies by HIV risk category among MSM in Vancouver.

We carried out an analysis of a serobehavioural study of men who have sex with men >19 years of age in Vancouver, Canada to examine HIV testing behaviour and use of risk reduction strategies by HIV risk category, as defined by routinely gathered clinical data. We restricted our analysis to those who self-identified as HIV-negative, completed a questionnaire, and provided a dried blood spot sample. Of 842 participants, 365 (43.3%) were categorised as lower-risk, 245 (29.1%) as medium-risk and 232 (27.6%) as higher-risk. The prevalence of undiagnosed HIV infection was low (lower 0.8%, medium 3.3%, higher 3.9%; p = 0.032). Participants differed by risk category in terms of having had an HIV test in the previous year (lower 46.5%, medium 54.6%, higher 67.0%; p < 0.001) and in their use of serosorting (lower 23.3%, medium 48.3%, higher 43.1%; p < 0.001) and only having sex with HIV-positive men if those men had low viral loads or were taking HIV medication (lower 5.1%, medium 4.8%, higher 10.9%; p = 0.021) as risk reduction strategies. These findings speak to the need to consider segmented health promotion services for men who have sex with men with differing risk profiles. Risk stratification could be used to determine who might benefit from tailored multiple health promotion interventions, including HIV pre-exposure prophylaxis.

The British Columbia Alcohol and Other Drug Monitoring System: Overview and Early Progress

This pilot project is a province-wide and nationally=supported collaboration intended to add value to existing monitoring and surveillance exercises that currently exist and are being developed in Canada. The fundamental aim is to create a system that generates a timely flow of data on hazardous patterns of substance use and related harms so as to inform public debate, to support effective policy, and to facilitate policy-relevant epidemiological research. Pilot and feasibility exercises have been conducted in relation to developing consistent questions in surveys of general and special populations, treatment system data, data on the contents of drugs seized by police, interviews with police, rates of alcohol and other drug mortality and morbidity, alcohol sales data, and data from the emergency departments. Wherever possible, links with the equivalent national data collection processes have been established to create consistencies. This article provides a general overview of the BC pilot monitoring system and discusses some potential advantages of planning and designing a comprehensive system with built-in consistencies across data collection elements.