Ekaterina Nosova

Knowledge of hepatitis C and treatment willingness amongst people who inject drugs in an era of direct acting antivirals

BACKGROUNDnKnowledge of hepatitis C virus (HCV) is believed to be important in altering risk behaviour, improving engagement in care, and promoting willingness to initiate HCV treatment. We assessed factors associated with HCV knowledge and treatment willingness amongst people who inject drugs (PWID) in an era of direct acting antivirals.nnnMETHODSnData were derived from three prospective cohort studies of PWID in Vancouver, Canada, between June 2014 and May 2015. HCV knowledge and treatment willingness were assessed using a Likert scale. Multivariable linear regression identified factors associated with higher HCV knowledge and treatment willingness.nnnRESULTSnAmongst 630 participants, mean scores for HCV knowledge and treatment willingness were 25.41 (standard deviation [SD]: 2.52) out of 30, and 6.83 (SD: 1.83) out of 10, respectively. In multivariable analyses, Caucasian ancestry (adjusted linear regression model estimate [β] 0.50; 95% confidence interval [CI] 0.17, 0.82), employment (β 0.76; 95% CI: 0.38, 1.13), diagnosed mental health disorder (β 0.44; 95% CI: 0.11, 0.78) and previous HCV treatment (β 0.94; 95% CI: 0.46, 1.43) were independently associated with higher knowledge. Downtown Eastside (DTES) residence (i.e., epicenter of Vancouvers drug scene) was independently associated with lower knowledge (β -0.48; 95% CI: -0.81, -0.15). Greater HCV knowledge (β 0.12; 95% CI: 0.07, 0.17) was independently associated with higher HCV treatment willingness. DTES residence (β -0.31; 95% CI: -0.56, -0.06) and daily crack cocaine smoking (β -0.52; 95% CI: -0.92, -0.13) were independently associated with lower treatment willingness.nnnCONCLUSIONnSocioeconomic factors, such as neighborhood residence and employment, were associated with HCV knowledge. Higher HCV knowledge was associated with more HCV treatment willingness. Our findings suggest that increasing HCV knowledge amongst PWID may be an integral component of the HCV cascade of care and that efforts might be best targeted to individuals with greater socioeconomic disadvantage.

Substance use patterns associated with recent exposure to fentanyl among people who inject drugs in Vancouver, Canada: A cross-sectional urine toxicology screening study

INTRODUCTIONnVancouver, Canada is experiencing an opioid overdose crisis where fentanyl, a potent, synthetic opioid contaminating the illicit drug supply, has been detected in the majority of fatal overdose cases. Despite its growing presence throughout North America, few studies have characterized exposure to fentanyl among people who use illicit drugs (PWUD). We sought to identify the prevalence and correlates of fentanyl exposure among PWUD in Vancouver.nnnMETHODSnData were derived from cohort studies of PWUD in Vancouver. In June-October 2016, we administered multi-panel urine drug screens (UDS) to detect recent exposure to fentanyl and eight other substances. Multivariable logistic regression was used to identify substance use patterns associated with recent fentanyl exposure among participants who injected drugs in the past six months (PWID).nnnRESULTSnAmong 669 PWUD including 250 (37.4%) females and 452 (67.6%) PWID, 97 (14.5%) tested positive for fentanyl. All these individuals also tested positive for other substances, most commonly for morphine/heroin (89.9%), amphetamine/methamphetamine (75.3%) and cocaine (74.2%). A fentanyl detection rate was significantly higher among PWID (19.7%) compared to non-injection drug users (3.9%) (p<0.001). In multivariable analyses, younger age (adjusted odds ratio [AOR]: 0.96) and testing positive for morphine/heroin (AOR: 6.73), buprenorphine (AOR: 4.25), amphetamine/methamphetamine (AOR: 3.26), cocaine (AOR: 2.92) and cannabis (AOR: 0.52) remained independently associated with fentanyl exposure (all p<0.05).nnnCONCLUSIONnWith one in five PWID being exposed to fentanyl, there is an urgent need to design and scale up interventions to reduce overdose risk, including a range of opioid agonist therapies.

Cessation of Injecting and Preceding Drug Use Patterns Among a Prospective Cohort of Street-Involved Youth

PURPOSEnInjection drug use is prevalent among street-involved youth, but patterns of cessation are poorly described. We identified drug use patterns preceding injection cessation among street-involved youth.nnnMETHODSnFrom September 2005 to May 2015, we collected data from the At-Risk Youth Study, a prospective cohort of street-involved youth in Vancouver, Canada, and limited the sample to actively injecting youth. The primary outcome was cessation of injecting self-reported at semiannual follow-up visits. We used Cox regression to identify drug use patterns preceding cessation.nnnRESULTSnAmong 383 youth, 65% were male, mean age was 22.3 (standard deviation, 2.5; range, 15-30) years, and 171 (45%) ceased injecting for 6xa0months or more (crude incidence density 22 per 100 person-years; 95% confidence interval [CI], 19-26). Youth who ceased were less likely to have injected daily (adjusted hazard ratio [AHR], .40; 95% CI, .28-.56), injected heroin (AHR, .40; 95% CI, .29-.56), or injected crystal methamphetamine (AHR, .43; 95% CI, .31-.59) before cessation. Noninjection heroin use was positively associated with injection cessation (AHR, 1.52; 95 CI, 1.12-2.08). Addiction treatment was not associated with cessation. At the time of cessation, 101 (59%) youth continued to use hard noninjection drugs such as heroin and crystal methamphetamine.nnnCONCLUSIONSnPeriods of injection cessation were common but frequently accompanied by ongoing noninjection drug use. Findings indicate that trajectories of injection drug use among youth are complex and highlight the need to further explore relationships between ongoing noninjection drug use and injection cessation.

Knowledge and possession of take-home naloxone kits among street-involved youth in a Canadian setting: a cohort study

BackgroundThe distribution of take-home naloxone (THN) kits has been an important strategy in reducing overdose fatalities among people who use drugs. However, little is known about the use of THN among youth who are street-involved. The present study explores knowledge and possession of THN among street-involved youth in a Canadian setting.MethodsData were derived from the At-Risk Youth Study (ARYS), a prospective cohort of street-involved youth age 14–28 at enrollment in Vancouver, Canada. Participants completed a standardized questionnaire, which included items related to knowledge and possession of THN, sociodemographic characteristics, and substance use-related factors. Multivariable logistic regression models were used to identify factors independently associated with knowledge and possession of THN.ResultsBetween December 2014 and November 2016, 177 youth were interviewed, including 68 females (38.4%). While 126 (71.2%) participants reported knowledge of THN, only 40 (22.6%) possessed a THN kit. Caucasian/white ethnicity was found to be positively associated with both knowledge and possession of THN (both pu2009<u20090.05). Public injection drug use in the last 6xa0months was found to be positively associated with knowledge of THN, while daily heroin use and daily methamphetamine use were associated with possession of THN (all pu2009<u20090.05). Male gender was negatively associated with possession of THN (pu2009<u20090.05).ConclusionsThese findings highlight important gaps between knowledge and possession of THN among youth and the need to increase participation in THN programs among specific populations including non-white and male youth. Further research is needed to gain a better understanding of the barriers that may prevent certain youth from acquiring THN kits.

Major depressive disorder and access to health services among people who use illicit drugs in Vancouver, Canada

BackgroundPeople who use illicit drugs (PWUD) are commonly diagnosed with major depressive disorder (MDD). However, little is known about whether PWUD living with MDD experience additional barriers to accessing health services compared to those without MDD. We sought to identify whether MDD symptoms were associated with perceived barriers to accessing health services among people who use illicit drugs (PWUD) in Vancouver, Canada.MethodsData were collected through prospective cohorts of PWUD in Vancouver, Canada between 2005 and 2016. Using multiple logistic regression, we examined the relationship between MDD symptoms, defined as a Centre for Epidemiologic Studies Depression (CES-D) scale total score of ≥16, and barriers to access health services. We also used descriptive statistics to examine common barriers among participants who reported any barriers.ResultsAmong a total of 1529 PWUD, including 521 (34.1%) females, 415 (27.1%) reported barriers to accessing health services, and 956 (62.5%) reported MDD symptoms at baseline. In multiple logistic regression analyses, after adjusting for a range of potential confounders, MDD symptoms (adjusted odds ratio [AOR]u2009=u20091.40; 95% confidence interval [CI]: 1.03–1.92) were positively and significantly associated with barriers to accessing health services. Among those who reported MDD symptoms and barriers to access, commonly reported barriers included: long wait lists/times (38.1%); and treated poorly by health care professionals (30.0%).ConclusionThese findings show that the likelihood of experiencing barriers to accessing health services was higher among PWUD with MDD symptoms compared to their counterparts. Policies and interventions tailored to address these barriers are urgently needed for this subpopulation of PWUD.

Criminalizing Sex Work Clients and Rushed Negotiations among Sex Workers Who Use Drugs in a Canadian Setting

Previous research indicates that criminalization of sex work is associated with harms among sex workers. In 2013, the Vancouver Police Department changed their sex work policy to no longer target sex workers while continuing to target clients and third parties in an effort to increase the safety of sex workers (similar to “end-demand sex work” approaches being adopted in a number of countries globally). We sought to investigate the trends and correlates of rushing negotiations with clients due to police presence among 359 sex workers who use drugs in Vancouver before and after the guideline change. Data were derived from three prospective cohort studies of people who use drugs in Vancouver between 2008 and 2014. We used sex-stratified multivariable generalized estimating equation models. The crude percentages of sex workers who use drugs reporting rushing client negotiations changed from 8.9% before the guideline change to 14.8% after the guideline change among 259 women, and from 8.6 to 7.1% among 100 men. In multivariable analyses, there was a significant increase in reports of rushing client negotiation after the guideline change among women (pxa0=xa00.04). Other variables that were independently associated with increased odds of rushing client negotiation included experiencing client-perpetrated violence (among both men and women) and non-heterosexual orientation (among women) (all pxa0<xa00.05). These findings indicate that despite the policing guideline change, rushed client negotiation due to police presence appeared to have increased among our sample of female sex workers who use drugs. It was also associated with client-perpetrated violence and other markers of vulnerability. These findings lend further evidence that criminalizing the purchase of sexual services does not protect the health and safety of sex workers.

Patterns of Transmitted Drug Resistance and Virological Response to First-line Antiretroviral Treatment Among Human Immunodeficiency Virus–Infected People Who Use Illicit Drugs in a Canadian Setting

BackgroundnTransmitted drug resistance (TDR) may compromise response to antiretroviral therapy (ART). However, there are limited data on TDR patterns and impacts among people who use illicit drugs (PWUD).nnnMethodsnData were drawn from 2 prospective cohorts of PWUD in Vancouver, Canada. We characterized patterns of TDR among human immunodeficiency virus (HIV)-infected PWUD, and assessed its impacts on first-line ART virological outcomes.nnnResultsnBetween 1996 and 2015, among 573 ART-naive PWUD (18% with recent HIV infection), the overall TDR prevalence was 9.8% (95% confidence interval [CI], 7.3%-12.2%), with an increasing trend over time, from 8.5% in 1996-1999 to 21.1% in 2010-2015 (P = .003), mainly driven by resistance to nonnucleoside reverse transcriptase inhibitors (NNRTIs). TDR-associated mutations were more common for NNRTIs (5.4%), followed by nucleoside reverse transcriptase inhibitors (3.0%) and protease inhibitors (1.9%). TDR prevalence was lower among recently infected PWUD (adjusted odds ratio, 0.39 [95% CI, .15-.87]). Participants with TDR had higher risk of virological failure than those without TDR (log-rank P = .037) in the first year of ART.nnnConclusionsnBetween 1996 and 2015, TDR prevalence increased significantly among PWUD in Vancouver. Higher risk of virological failure among PWUD with TDR may be explained by some inappropriate ART prescribing, as well as undetected minority resistant variants in participants with chronic HIV infection. Our findings support baseline resistance testing early in the course of HIV infection to guide ART selection among PWUD in our setting.

The relationship between parental heavy drinking and non-fatal overdose among people who inject drugs in Vancouver, Canada

BACKGROUNDnDespite the acute drug-related and behavioural risk factors for experiencing a drug overdose, few remote childhood experiences have been examined as risk factors for subsequent later life overdose risk. Parental heavy drinking has been associated with some later life negative outcomes, but little is known regarding the impact on drug overdoses, especially among people who inject drugs. Given the current overdose crisis in North America, we sought to evaluate the impact of parental heavy drinking on later life non-fatal overdose among people who inject drugs in Vancouver, Canada.nnnMETHODSnData were derived from two prospective cohort studies of community-recruited people who inject drugs in Vancouver between December 2012 and May 2016. We employed multivariable generalized estimating equations to examine the relationship between parental heavy drinking and non-fatal overdose in the past six months.nnnRESULTSnAmong 327 eligible participants, 111 (33.9%) reported parental heavy drinking and 95 (29.1%) reported a non-fatal overdose at least once during the study period. In a multivariable analysis, experiencing parental heavy drinking remained independently associated with non-fatal overdose (adjusted odds ratio: 1.69; 95% confidence interval: 1.07-2.66) after adjustment for a range of socio-demographic and drug using confounders.nnnCONCLUSIONSnThese findings suggest long-term negative impacts of parental heavy drinking, on subsequent risk taking or other mechanisms associated with overdose. Current overdose prevention efforts may benefit from the evaluation of life course vulnerabilities that may be amenable to earlier interventions.

Prevalence of Heavy Alcohol Use Among People Receiving Methadone Following Change to Methadose

ABSTRACT Background: A recent switch in methadone formulation from methadone (1 mg/mL) to Methadose (10 mg/mL) in British Columbia (BC), Canada, was associated with increased reports of opioid withdrawal and increases in illicit opioid use. Impacts on other forms of drug use have not been assessed. Since alcohol use is common among people receiving Medication-Assisted Treatment (MAT), we assessed if switch was associated with increased prevalence of heavy alcohol use. Methods: Drawing on data from two open prospective cohort studies of people who inject drugs in Vancouver, BC, generalized estimating equations (GEE) model examined relationship between methadone formulation change and heavy alcohol use, defined by National Institute for Alcohol Abuse and Alcoholism (NIAAA). A sub-analysis examined relationship with heavier drinking defined as at least eight drinks per day on average in last six months. Results: Between June 2013 and May 2015, a total of 787 participants on methadone were eligible for the present analysis, of which 123 (15.6%) reported heavy drinking at least once in last six months. In an unadjusted GEE model, Methadose use was not significantly associated with an increased likelihood of heavy drinking [Odds Ratio (OR) = 1.03; 95% Confidence interval (CI) = 0.87–1.21]. Methadose use was not significantly associated with an increased likelihood of drinking at least eight drinks daily on average (OR = 1.09, 95% CI = 0.72–1.65). Conclusions: Despite reported changes in opioid use patterns coinciding with the change, there appeared to be no effect of the methadone formulation change on heavy drinking in this setting.

Use of withdrawal management services among people who use illicit drugs in Vancouver, Canada

BackgroundFor many individuals with substance use disorders, the entry point for addiction treatment can be through withdrawal management (e.g. detoxification) services. However, little is known about the factors that predict withdrawal management service use among people who use illicit drugs (PWUD). Using data derived from two prospective cohorts of PWUD, we conducted a longitudinal data analysis of factors associated with use of withdrawal management services.MethodsIndividuals participating in two cohorts of PWUD were prospectively followed between December 2005 and May 2016 in Vancouver, Canada. Bivariate and multivariate generalized estimating equations were used to examine factors associated with use of withdrawal management services.ResultsOut of a total of 2001 participants, 339 (16.9%) individuals reported having been to a withdrawal management centre in the previous 6 months at some point during the study period. In multivariate analyses, male sex (adjusted odds ratio [AOR]: 1.62, 95% Confidence Interval [CI]: 1.17–2.24), homelessness (AOR: 1.86, 95% CI: 1.45–2.38), binge use of any substance (AOR: 1.34, 95% CI: 1.08–1.67), having attended a supervised injection facility (AOR: 1.66, 95% CI: 1.3–2.11), and having accessed other addiction medicine treatment or supports (other than withdrawal management services or opioid agonist therapy; AOR: 3.34, 95% CI: 2.64–4.22) were positively associated with having accessed withdrawal management services, whereas older age (AOR: 0.81, 95% CI: 0.7–0.94) was negatively associated with the outcome.ConclusionsThis study identified specific factors associated with accessing withdrawal management services. Current evidence suggests a need to re-examine the provision of withdrawal management services. Consideration needs to be given to redesigning access to care and bridging to evidence-based addiction treatment, particularly for highly vulnerable subpopulations, identified in this study as females and older people.