Kanna Hayashi

Residential eviction and exposure to violence among people who inject drugs in Vancouver, Canada

BACKGROUNDnPeople who inject drugs (PWID) experience markedly elevated rates of physical and sexual violence, as well as housing instability. While previous studies have demonstrated an association between homelessness and increased exposure to violence among PWID, the relationship between residential eviction and violence is unknown. We therefore sought to examine the association between residential eviction and experiencing violence among PWID in Vancouver, Canada.nnnMETHODSnData were derived from two open prospective cohort studies of PWID: the Vancouver Injection Drug Users Study (VIDUS) and the AIDS Care Cohort to evaluate Exposure to Survival Services (ACCESS). We used generalized estimating equations (GEE) to estimate the relationship between residential eviction and experiencing violence among male and female PWID, respectively.nnnRESULTSnBetween June 2007 and May 2014, 1689 participants were eligible for the analysis, contributing a median of 5.5 years of follow-up. Of these, 567 (33.6%) were female. In total, 259 (45.7%) of females and 566 (50.4%) of males experienced at least one incident of violence over the study period. In multivariable GEE models, residential eviction was independently associated with greater odds of experiencing violence among both females (Adjusted Odds Ratio [AOR]=2.09; 95% confidence interval [CI]: 1.39-3.13) and males (AOR=1.95; 95% CI=1.49-2.55), after adjustment for potential confounders.nnnCONCLUSIONnResidential eviction was independently associated with an increased likelihood of experiencing violence among both male and female PWID. These findings point to the need for evidence-based social-structural interventions to mitigate housing instability and violence among PWID in this setting.

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.

High prevalence of quasi-legal psychoactive substance use among male patients in HIV care in Japan: a cross-sectional study

BackgroundSyndemics of illicit drug use and HIV remain as significant public health issues around the world. There has been increasing concern regarding the rapidly growing market of new psychoactive substances, particularly in Asia. In response, the Japanese government has increasingly banned such substances in recent years. We sought to identify the prevalence and correlates of use of quasi-legal psychoactive substances among people living with HIV/AIDS (PLHIV) in Japan.MethodsData were derived from a nationwide survey of PLHIV conducted at nine leading HIV/AIDS care hospitals between July and December 2013. The prevalence and correlates of the use of quasi-legal psychoactive substances (e.g., synthetic cannabinoids, cathinone derivatives, etc. that had not been prohibited from using at the time of survey) among male participants were examined using multivariate survey logistic regression.ResultsAmong 963 study participants, the majority (95.3%) were male. The most commonly used drug among men was quasi-legal psychoactive substances (55.3% ever and 12.8% in the previous year). In multivariate analysis, the lifetime use of tryptamine-type derivatives (i.e., 5-MeO-DIPT or N,N-diisopropyl-5-methoxytryptamine) (adjusted odds ratio [AOR]: 2.42; 95% confidence interval [CI]: 1.36–4.28) and methamphetamine/amphetamine (AOR: 3.59; 95% CI: 2.13–6.04) were independently associated with recent quasi-legal psychoactive substance use.ConclusionsIn our sample of male PLHIV in Japan, quasi-legal psychoactive substances were the most commonly used drugs. Individuals who had ever used tryptamine-type derivatives or methamphetamine/amphetamine were more likely to report recent quasi-legal psychoactive substance use, suggesting a potential shift in drug use patterns from regulated to unregulated substances among this population. These findings indicate a need for further research to examine implications for HIV care.

Declining rates of health problems associated with crack smoking during the expansion of crack pipe distribution in Vancouver, Canada

BackgroundCrack cocaine smoking is associated with an array of negative health consequences, including cuts and burns from unsafe pipes, and infectious diseases such as HIV. Despite the well-established and researched harm reduction programs for injection drug users, little is known regarding the potential for harm reduction programs targeting crack smoking to reduce health problems from crack smoking. In the wake of recent crack pipe distribution services expansion, we utilized data from long running cohort studies to estimate the impact of crack pipe distribution services on the rates of health problems associated with crack smoking in Vancouver, Canada.MethodsData were derived from two prospective cohort studies of community-recruited people who inject drugs in Vancouver between December 2005 and November 2014. We employed multivariable generalized estimating equations to examine the relationship between crack pipe acquisition sources and self-reported health problems associated with crack smoking (e.g., cut fingers/sores, coughing blood) among people reported smoking crack.ResultsAmong 1718 eligible participants, proportions of those obtaining crack pipes only through health service points have significantly increased from 7.2% in 2005 to 62.3% in 2014 (pu2009<u20090.001), while the rates of reporting health problems associated with crack smoking have significantly declined (pu2009<u20090.001). In multivariable analysis, compared to those obtaining pipes only through other sources (e.g., on the street, self-made), those acquiring pipes through health service points only were significantly less likely to report health problems from smoking crack (adjusted odds ratio: 0.82; 95% confidence interval: 0.73–0.93).ConclusionsThese findings suggest that the expansion of crack pipe distribution services has likely served to reduce health problems from smoking crack in this setting. They provide evidence supporting crack pipe distribution programs as a harm reduction service for crack smokers.

Declining Mortality Rates in HIV-Infected People Who Inject Drugs During a Seek-and-Treat Initiative in Vancouver, Canada, 1996–2014: A Prospective Cohort Study

We estimated rates and predictors of death among a community-recruited prospective cohort of 961 human immunodeficiency virus (HIV)-infected people who inject drugs in Vancouver, Canada, between 1996 and 2014. The results demonstrated significant declines in age-adjusted all-cause and HIV-related mortality rates since 2010, coincident with the scale-up of a community-wide seek-and-treat campaign.

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.

High-intensity cannabis use is associated with retention in opioid agonist treatment: a longitudinal analysis: Cannabis use and opioid agonist treatment

BACKGROUND AND AIMSnCannabis use is common among people on opioid agonist treatment (OAT), causing concern for some care providers. However, there is limited and conflicting evidence on the impact of cannabis use on OAT outcomes. Given the critical role of retention in OAT in reducing opioid-related morbidity and mortality, we aimed to estimate the association of at least daily cannabis use on the likelihood of retention in treatment among people initiating OAT. As a secondary aim we tested the impacts of less frequent cannabis use.nnnDESIGNnData were drawn from two community-recruited prospective cohorts of people who use illicit drugs (PWUD). Participants were followed for a median of 81xa0months (interquartile rangexa0=xa037-130).nnnSETTINGnVancouver, Canada.nnnPARTICIPANTSnThis study comprised a total of 820 PWUD (57.8% men, 59.4% of Caucasian ethnicity, 32.2% HIV-positive) initiating OAT between December 1996 and May 2016. The proportion of women was higher among HIV-negative participants, with no other significant differences.nnnMEASUREMENTSnThe primary outcome was retention in OAT, defined as remaining in OAT (methadone or buprenorphine/naloxone-based) for two consecutive 6-month follow-up periods. The primary explanatory variable was cannabis use (at least daily versus less than daily) during the same 6-month period. Confounders assessed included: socio-demographic characteristics, substance use patterns and social-structural exposures.nnnFINDINGSnIn adjusted analysis, at least daily cannabis use was positively associated with retention in OAT [adjusted odds ratio (aOR)xa0=xa01.21, 95% confidence interval (CI)xa0=xa01.04-1.41]. Our secondary analysis showed that compared with non-cannabis users, at least daily users had increased odds of retention in OAT (aORxa0=xa01.20, 95% CIxa0=xa01.02-1.43), but not less than daily users (aORxa0=xa01.00, 95% CIxa0=xa00.87-1.14).nnnCONCLUSIONSnAmong people who use illicit drugs initiating opioid agonist treatment in Vancouver, at least daily cannabis use was associated with approximately 21% greater odds of retention in treatment compared with less than daily consumption.

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.