Active Injection Drug Users Research Articles

Should active injecting drug users receive treatment for chronic hepatitis C?

Accumulating data propose that active injecting drug users might not differ from the general population in terms of sustained virological response when adherent to therapy for chronic hepatitis C. However, current guidelines contain restrictive recommendations for therapy in this group of patients. Therefore, we evaluated a cohort of chronic hepatitis C patients regarding the potent influence of active drug using on initial informed consent, compliance and sustained virological response to treatment. For that purpose, 162 consecutive patients (of which 62 active injecting drug users), who had been evaluated during the last 6 years in our center for chronic hepatitis C and proposed to receive treatment with pegylated interferon alpha and ribavirin, were enrolled. Initial informed consent, compliance, and sustained virological response as well as data regarding age, gender, body mass index, genotype, viral load, coinfection with HBV/HDV/HIV, administered interferon alpha (2a or 2b), liver function tests, liver histology, urban residence, ethnicity, and concomitant use of alcohol were collected and analyzed in respect with injecting drug using. Injecting drug using was positively correlated with male gender (P<0.001), young age (P<0.001), native origin (P = 0.043), and concomitant use of alcohol (P<0.001). Comparable initial informed consent (P = 0.836), compliance (P = 0.879), and sustained virological response (P = 0.132) were observed between injecting drug users and non- injecting drug users. The results were confirmed using a multiple regression model. Our data further support that active injecting drug users do not constitute a distinct chronic hepatitis C patient group in terms of initial informed consent, compliance, or sustained virological response. Therefore, injecting drug using should not be a major determinant influencing the decision for treatment of chronic hepatitis C in eligible patients.

P70 Can antiviral therapy for hepatitis C reduce the prevalence of HCV among injecting drug user populations? A modelling analysis of its prevention utility

IntroductionHCV antiviral treatment (peginterferon and ribavirin) is effective for individual patients, but few active injecting drug users (IDUs) are treated.AimWe considered the utility of antiviral treatment for reducing HCV transmission...

Sexual Mixing and Condom Use with Different Types of Sex Partners among Non-Institutionalized Sexually Active Female Injecting Drug Users in Sichuan, China

Behavioral surveillance data of 1422 sexually active female injecting drug users (IDU) in Sichuan China were analyzed. The prevalence of syringe-sharing was 43.5%. Respectively, 59.0%, 38.5% and 55.7% had regular, non-regular, and commercial sex-partner (RP, NRP, and CSP); 44.3% had multiple types of sex partners; 23.6 and 36.2% of those with RP had NRP and CSP. The prevalence of unprotected sex (last episode) with RP, NRP and CSP were respectively 75.4%, 50.7% and 39.3%; these three variables were associated with each other and with syringe sharing (univariate OR = 1.58-30.13). About 85% of the participants had attempted quitting drug use; the experience was not associated with condom use. HIV voluntary counseling and testing was associated with lower likelihood of unprotected sex with RP, NRP and CSP (multivariate OR= 0.44-0.60); the coverage was only 40.7%. Potential bridging of HIV transmission from IDU to non-IDU populations is a serious concern.

Antiretroviral Use Among Active Injection-Drug Users: The Role of Patient–Provider Engagement and Structural Factors

HIV-seropositive, active injection-drug users (IDUs), compared with other HIV populations, continue to have low rates of highly active antiretroviral therapy (HAART) use, contributing to disparities in their HIV health outcomes. We sought to identify individual-level, interpersonal, and structural factors associated with HAART use among active IDUs to inform comprehensive, contextually tailored intervention to improve the HAART use of IDUs. Prospective data from three semiannual assessments were combined, and logistic general estimating equations were used to identify variables associated with taking HAART 6 months later. Participants were a community sample of HIV-seropositive, active IDUs enrolled in the INSPIRE study, a U.S. multisite (Baltimore, Miami, New York, San Francisco) prevention intervention. The analytic sample included 1,225 observations, and comprised 62% males, 75% active drug users, 75% non-Hispanic blacks, and 55% with a CD4 count <350; 48% reported HAART use. Adjusted analyses indicated that the later HAART use of IDUs was independently predicted by patient-provider engagement, stable housing, medical coverage, and more HIV primary care visits. Significant individual factors included not currently using drugs and a positive attitude about HAART benefits even if using illicit drugs. Those who reported patient-centered interactions with their HIV primary care provider had a 45% greater odds of later HAART use, and those with stable housing had twofold greater odds. These findings suggest that interventions to improve the HIV treatment of IDUs and to reduce their HIV health disparities should be comprehensive, promoting better patient-provider engagement, stable housing, HAART education with regard to illicit drug use, and integration of drug-abuse treatment with HIV primary care.

Ongoing drug use and outcomes from highly active antiretroviral therapy among injection drug users in a Canadian setting

The effect of ongoing illicit drug use on HIV treatment remains controversial, especially in countries where access to HIV treatment for active injection drug users (IDUs) is limited because of presumed non-adherence. We sought to investigate the influence of drug use patterns on adherence to antiretroviral therapy and virological suppression among IDUs. Using generalized estimating equation logistic regression, we explored the effect of abstinence versus ongoing drug use on adherence and virological suppression using data from a community-recruited cohort of IDUs in Vancouver (BC, Canada). A total of 381 HIV-positive IDUs were included in this analysis, among whom the median follow-up time was 30 months. In a multivariate model, no relationship was found between abstinence (reference) and active injection (adjusted odds ratio [AOR] 0.88, 95% confidence interval [CI] 0.65-1.17) and non-injection (AOR 0.97, 95% CI 0.67-1.41) drug use with adherence. In subanalyses, ongoing injection drug use was associated with a lower odds of virological suppression in comparison to abstinence (AOR 0.74, 95% CI 0.57-0.97; P=0.026) and both active IDUs and active non-IDUs had lower odds of virological suppression compared with abstinent participants when longer periods of virological suppression were considered. Given the absence of a strong relationship between abstinence and ongoing drug use and adherence among HIV-positive IDUs, programmes that restrict antiretrovirals to abstinent individuals should be re-examined. The lower rates of virological suppression associated with ongoing drug use nevertheless highlight the importance of comprehensive systems of care and addiction treatment for active drug users.

Temporal Trends in Highly Active Antiretroviral Therapy Initiation among Injection Drug Users in Baltimore, Maryland, 1996–2008

We characterized temporal trends in highly active antiretroviral therapy (HAART) initiation (1996-2008) among treatment-eligible persons in a community-based cohort of current and former injection drug users (IDUs) in Baltimore, Maryland. The AIDS Linked to the IntraVenous Experience (ALIVE) cohort has been observing human immunodeficiency virus (HIV)-positive IDUs since 1988. HAART eligibility was defined as the first visit after 1 January 1996 at which the patient's CD4(+) cell count was <350 cells/microL. Temporal trends and predictors of HAART initiation were examined using chi(2) tests for trend and lognormal survival models. The median age of 582 HAART-eligible IDUs was 41 years; 75% of the subjects were male, 97% were African American, and 60% were active IDUs. Of these 582 individuals, 345 initiated HAART over 1803 person-years (19.2 subjects per 100 person-years; 95% confidence interval, 17.2-21.3 subjects per 100 person-years); there was no statistically significant temporal trend in HAART initiation. Independent predictors of delayed initiation included heavy injection drug use; having a prior AIDS diagnosis, having a lower CD4(+) cell count, having a usual source of care, and having health insurance were predictors of more-rapid initiation. The delay between eligibility and initiation decreased among those who became eligible most recently (2003-2007), compared with those in earlier periods (1996-2002); however, a substantial number of patients who became eligible in recent years either initiated HAART after a substantial delay or did not initiate HAART at all. We failed to observe substantial improvement in HAART initiation among current and former IDUs over a 12-year period; heavy use of injection drugs remains the major barrier to HAART initiation and to consistent HIV care. The fact that many IDUs initiate HAART after a significant delay or do not initiate it at all raises concern that disparities in HIV care for IDUs remain at a time of simplified antiretroviral regimens and increasing adoption of earlier treatment.

HIV prevalence among female sex workers, drug users and men who have sex with men in Brazil: A Systematic Review and Meta-analysis

BackgroundThe Brazilian response towards AIDS epidemic is well known, but the absence of a systematic review of vulnerable populations ─ men who have sex with men (MSM), female sex workers (FSW), and drug users (DU) remains a main gap in the available literature. Our goal was to conduct a systematic review and meta-analysis of studies assessing HIV prevalence among MSM, FSW and DU, calculating a combined pooled prevalence and summarizing factors associated the pooled prevalence for each group.MethodsNine electronic databases (MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE, AMED, CINAHL, TOXNET, SciELO, and ISI-Web of Science) were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1999 to 2009. To be included in the review, studies had to measure HIV prevalence and/or incidence as the primary outcome among at least one specific population under analysis.ResultsThe studies targeting the three populations analyzed mostly young participants aged 30 years or less. Among FSW, eight studies were selected (3,625 participants), consistently identifying higher condom use with sexual clients than with occasional and stable partners. The combined HIV prevalence for FSW was 6.2 (95% CI: 4.4-8.3). Ten studies targeting MSM were identified (6,475 participants). Unprotected anal intercourse was commonly reported on those studies, but with great variability according to the nature of the relationship - stable vs. occasional sex partners - and sexual practice - receptive vs. insertive anal sex. Pooled HIV prevalence for MSM was 13.6 (95% CI: 8.2-20.2). Twenty nine studies targeting DU were identified (13,063 participants). Those studies consistently identified injection drug use and syringe/needle sharing as key predictors of HIV-infection, as well as engagement in sex work and male-to-male sex. The combined HIV prevalence across studies targeting DU was 23.1 (95% CI: 16.7-30.2).ConclusionsFSW, MSM and DU from Brazil have a much risk of acquiring HIV infection compared to the general population, among which HIV prevalence has been relatively low (~0.6%). Those vulnerable populations should be targeted by focused prevention strategies that provide accurate information, counseling and testing, as well as concrete means to foster behavior change (e.g. access to condoms, drug abuse treatment, and clean syringes in the case of active injecting drug users), tailored to gender and culture-specific needs. Programs that provide these services need to be implemented on public health services throughout the country, in order to decrease the vulnerability of those populations to HIV infection.

Prevalence of HIV/HCV/HBV infections and drug-related risk behaviours amongst IDUs recruited through peer-driven sampling in Iran

Background The control of blood-borne infections including HIV and hepatitis C (HCV) amongst injecting drug users (IDUs) is a challenge for health authorities in Iran. Hence, more reliable estimates of the levels of blood-borne infections and their associated factors are critically needed. Methods Active IDUs were recruited using peer-driven sampling in a bio-behavioural survey in 2008. Over 8 weeks, data were collected from adults living in a city in Isfahan Province who had injected drugs in the past month. Participants provided a whole blood sample and answered questions on sexual and drug-related risk characteristics. Participants were provided post-test counselling and a non-monetary incentive for their participation. Excluding two inactive cases, the initial recruits resulted in 2–8 waves of recruitment. Results Overall, 118 IDUs including three females participated. The estimated population proportions of HIV, hepatitis B, and HCV infections were 0.7% (95% CI, 0.6–2.3), 0.7% (95% CI, 0.1–2.1), and 59.4% (95% CI, 47.4–68.7), respectively. Responses indicated that 31% (95% CI, 20–44.5) of the IDUs ever shared a needle/syringe for drug injection, and 77% (95% CI, 65–84) had ever injected an addictive solution marketed widely as Temgesic. Multivariate analyses revealed that the high prevalence of HCV infection amongst IDUs is associated with the lifetime duration of drug injection (AOR, 1.17; 95% CI, 1.01–1.34) and with having injected Temgesic (AOR, 4.73; 95% CI, 1.52–14.69). Conclusion Our experience in Iran indicates that IDUs can be recruited effectively in a bio-behavioural survey through peer-driven sampling and using only a single primary incentive. The high prevalence of HCV associated with injecting Temgesic is important evidence for harm-reduction policies in Iran.

Recent Incarceration Linked to Cutaneous Injection-Related Infections Among Active Injection Drug Users in a Canadian Setting

Cutaneous injection-related infections (CIRI), such as abscesses and cellulitis, are the cause of a substantial burden of morbidity and mortality among injection drug users (IDU). The possible contribution of exposure to correctional environments to CIRI risk has not been fully investigated. Thus, we sought to test the possible relationship between incarceration and CIRI using data from a community-based sample of IDU. Data for these analyses was from the Scientific Evaluation of Supervised Injecting (SEOSI) cohort, linked with administrative records of a local ED in Vancouver, Canada. Using longitudinal analysis we assessed the relationship between the number of ED visits for CIRI care and recent incarceration in a multivariate model including information on possible confounders. Between June 2004 and December 2006, 901 individuals were eligible for our analysis. Of these, 214 (9.6%) visited the ED for CIRI care at least once during the study period. The incidence of ED care for CIRI was 72.9 per 100 person years. In a multivariate model, recent incarceration was associated with a greater number of ED visits for CIRI care (adjusted relative rate = 1.56, 95% confidence interval: 1.31-1.85, P < 0.001). The need for ED treatment for CIRI was common among a sample of local IDU. Exposure to correctional environments was an independent risk factor for visiting the ED for CIRI care, suggesting improvements in infection control in local prisons is urgently needed.

Utility of the Beck Depression Inventory to screen for and track depression in injection drug users seeking hepatitis C treatment

Objective Treating acute hepatitis C (HCV) in injection drug users (IDUs) is complicated by a high prevalence of psychiatric comorbidities that may lead to increased risk for depressive complications of interferon treatment. Effective screening strategies are needed to help non-psychiatric clinicians identify depressive disorders. Methods Thirty IDUs with acute HCV completed the Beck Depression Inventory (BDI), underwent a psychiatric examination, and were randomized to 24 weeks of pegylated interferon treatment (IFA) or observation (OBS). Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of the BDI for diagnosing depression (with a cutoff >10) were calculated. The psychiatrist's diagnosis was used as the gold standard. Depression severity was assessed over time with the BDI. Results Forty-seven percent of individuals met criteria for a depressive disorder. Sensitivity (91%) and NPV (92%) were high for the BDI; specificity (58%) and PPV (56%) were low. BDI worsened in 2 patients completing the study (one IFA, one OBS); two IFA patients were discontinued for possible depression-related complications. At baseline, subject-rated fatigue was associated with alanine aminotransferase level. Conclusion The BDI is an adequate tool for ruling out depressive disorders in active IDUs with acute HCV, but specificity is low. Psychiatric consultation is recommended for all active IDUs being considered for acute HCV treatment.

Factors Associated with Recruiting an HIV Seropositive Risk Network Member Among Injection Drug Users

Using a social network approach to recruitment, we analyzed the factors that predicted recruitment of an HIV seropositive network member by active injection drug users (IDUs). IDUs were asked to bring in drug and sex network members, whom they delineated on a social network inventory. The 297 index participants recruited 425 networks, of whom 17.3% were seropositive. The majority of seropositive members were recruited by IDUs who reported no seropositive risk network members. The strongest predictor of recruiting seropositives was ethnicity, with African American indexes more than 3 times more likely than others to recruit seropositives as compared to other ethnic groups. Those African American indexes who reported that they had no seropositive network members were over 10 times more likely to recruit a seropositive. These results suggest the feasibility to target active drug users to recruit seropositives and emphasize the public health importance of focusing network approaches on the networks of African American IDUs.

Risk Practices Associated with Bacterial Infections among Injection Drug Users in Denver, Colorado

Background: There has been limited research on bacterial infections (e.g., skin and soft tissue abscesses, endocarditis) among injection drug users (IDUs), despite these infections often resulting in serious morbidity and costly medical care. Although high-risk practices that contribute to bacterial infections are not entirely clear, certain injection practices have been found to increase risk in past studies. Objectives: The objectives of this study are to examine rates of bacterial infections among IDUs in Denver, Colorado, and high-risk practices that predict skin infections. Methods: Structured interviews were conducted with 51 active heroin, cocaine, and methamphetamine IDUs (over 18 years). Results: Among all participants, 55% reported a lifetime history of at least one skin infection, and 29% reported having an infection in the last year. Those with a skin infection in the last year were significantly more likely to inject intramuscularly (OR = 1.57) and to report greater heroin injection frequency (OR = 1.08) compared to IDUs with no history of skin infections. Heroin and speedball injectors reported a higher number of past abscesses compared to methamphetamine and cocaine injectors. Conclusion: Intervention strategies to reduce bacterial infections should focus on high-risk injection practices. Scientific Significance: Learning about rates of bacterial infections and high-risk practices associated with these infections can benefit researchers developing risk reduction interventions for IDUs.

Spontaneous Control of Primary Hepatitis C Virus Infection and Immunity Against Persistent Reinfection

We followed patients with ongoing hepatitis C virus (HCV) exposure following control of an initial HCV infection to determine whether primary control conferred protection against future persistent infections. Twenty-two active injection drug users (IDU) who had cleared a primary hepatitis C viremia for at least 60 days were monitored monthly. Reinfection was defined as the detection of a new HCV infection. Protection was assessed based on the magnitude and duration of viremia following reinfection and generation of T-cell and neutralizing antibody (nAb) responses. Reinfection occurred in 11 IDU (50%) who previously spontaneously controlled primary HCV infection. Although viral clearance occurs in approximately 25% of patients with primary infections, spontaneous viral clearance was observed in 83% of reinfected patients. The duration and maximum level of viremia during subsequent episodes of reinfection were significantly decreased compared with those of the primary infection in the same subjects. In contrast to chronic infection, reinfection was associated with a significant increase in the breadth of T-cell responses. During acute infection, nAbs against heterologous viral pseudoparticles were detected in 60% of reinfected subjects; cross-reactive nAbs are rarely detected in patients who progress to chronic infection. HCV reinfection is associated with a reduction in the magnitude and duration of viremia (compared with the initial infection), broadened cellular immune responses, and generation of cross-reactive humoral responses. These findings are consistent with development of adaptive immunity that is not sterilizing but protects against chronic disease.

Characterization of the Emerging HIV Type 1 and HCV Epidemics among Injecting Drug Users in Dushanbe, Tajikistan

This study aimed to determine HIV, HCV, and syphilis prevalence and correlates, and to characterize the molecular epidemiology of HIV-1 among injecting drug users (IDUs) in Dushanbe, Tajikistan. A cross-sectional study assessing risk factors for HIV and HCV through an interview administered survey was conducted. A total of 491 active adult IDUs were recruited from May to November 2004 in Dushanbe, Tajikistan. HIV-1 antibody status was determined with rapid testing and confirmed with ELISA. HCV antibody testing was conducted using a BIOELISA HCV kit. HIV-1 subtyping was done on a subset with full-length sequencing. Correlates of HIV and HCV infection were assessed using logistic regression. Overall prevalence of HIV was 12.1%, HCV was 61.3%, and syphilis was 15.7%. In a multivariate logistic regression model controlling for gender and ethnicity, daily injection of narcotics [odds ratio (OR) OR 3.22] and Tajik nationality (OR 7.06) were significantly associated with HIV status. Tajik nationality (OR 1.91), history of arrest (OR 2.37), living/working outside Tajikistan in the past 10 years (OR 2.43), and daily injection of narcotics (OR 3.26) were significantly associated with HCV infection whereas being female (OR 0.53) and always using a sterile needle (OR 0.47) were inversely associated with HCV infection. Among 20 HIV-1-positive IDU with specimens available for typing, 10 were subtype A, 9 were CRF02_AG, and one was an A-CRF02_AG recombinant. Epidemics of HIV-1, HCV, and drug use are underway in Dushanbe. The molecular epidemiology is distinctive, with West African variants accounting for roughly 50% of prevalent infections. Targeted prevention programs offering both needle exchange programs and opiate substitution therapies are urgently called for to prevent the further spread of HIV and HCV in Tajikistan.

Factors associated with treatment failure of patients with psychiatric diseases and injecting drug users in the treatment of genotype 2 or 3 hepatitis C chronic infection

Genotype 2/3 hepatitis C virus (HCV) has a good response to treatment with peginterferon and ribavirin. Patients with psychiatric disorders and injecting drug users (IDUs) are considered 'difficult to treat' and are often excluded from treatment despite the lack of evidence supporting this decision. To investigate the outcome and factors associated with treatment failure in these groups. This is an observational study of a cohort of patients infected by genotype 2/3 HCV. IDUs and patients with psychiatric diseases were not excluded from treatment. We performed an intention-to-treat analysis to evaluate factors related to treatment failure. A sustained virological response (SVR) was achieved in 91 of the 125 patients treated (72.8%). Patients with chronic psychotic disorders or former IDUs had SVR rates similar to other groups. After multivariate analysis, independent factors associated with treatment failure were liver cirrhosis [odds ratio (OR) 3.4, 95% confidence interval (CI) 1.1-10.4], a history of depression and not being on antidepressants at the commencement of HCV treatment (OR 4.4, 95% CI 1.2-16) and active IDUs (OR 7.3, 95% CI 1.77-30.4). Patients with a history of depression who were not receiving antidepressants and active IDUs are more likely to fail treatment for genotype 2/3 HCV and will need additional support.

High prevalence of unprotected sex among Finnish HIV-positive and HIV-negative injecting drug users

To study the prevalence of sexual risk behaviour and to identify factors associated with inconsistent condom use of Finnish injecting drug users (IDUs), and thus to examine the potential of sexual transmission of HIV within and from this population. HIV-positive (n = 89) and HIV-negative (n = 207) IDUs from the Helsinki metropolitan area were interviewed using a standardized questionnaire. Determinants of inconsistent condom use in the past 6 months were analyzed with logistic regression. Inconsistent condom use was reported by 63% (39) of HIV-positive and 80% (144) of HIV-negative sexually active IDUs. Unprotected sex was more common in steady relationships (OR 5.6, CI 2.4-13.4). Inconsistent condom use was also associated with recent inpatient addiction treatment especially in the HIV-positive group (OR 15.7, 95% CI 1.7-143.0). Inpatient or outpatient addiction treatment was reported by 72% of the participants. Inconsistent condom use was not associated with age, gender, drug use frequency or markers of marginalization (unstable living, unemployment). Inconsistent condom use allows for the spread of HIV and other sexually transmitted infections among Finnish IDUs. Addiction treatment programmes should include interventions focused on sexual behaviour to all of their clients. Partners of IDUs should be actively offered HIV counselling and testing.

Pilot Trial of an Intervention Aimed at Modifying Drug Preparation Practices Among Injection Drug Users in Puerto Rico

Injection drug users (IDUs) contaminate preparation materials with blood-borne pathogens by using syringes as measuring and dispensing devices. In collaboration with IDUs, we developed a preventive intervention consisting of four new preparation practices aimed at avoiding the use of syringes in the preparation, and reducing the contamination of the materials. This report describes the results of a pilot trial introducing the new practices to ascertain their adoption potential and their potential efficacy in reducing contamination. Participants comprised 37 active IDUs among whom the new practices were promoted during 16 weeks. In addition to self-reported behaviors, the study collected cookers and plastic caps from shooting galleries and tested them for the presence of blood residues. Adoption rates were: (1) cleaning of skin area with hand sanitizer--65.6%; (2) directly pouring water with a dropper into the cooker--56.3%; (3) drawing drug solution with a preparation syringe and syringe filter--34.4%; and, (4) backload rinsing syringes--53.1%. Rates of blood residues detected in cookers and plastic caps were 41.7% prior to the trial, 28.6% at week 8, 24.6% at week 14, and 12.0% at week 18. We believe the results of the pilot trial are compelling and suggest that this intervention merits further formal testing.

Association between neighbourhood socioeconomic characteristics and high-risk injection behaviour amongst injection drug users living in inner and other city areas in Montréal, Canada

Background Area-level socioeconomic conditions are associated with epidemic rates of viral hepatitis and HIV amongst urban injection drug users (IDUs), but whether specific socioeconomic markers are uniformly related to IDU outcomes across different urban environments is unclear. We evaluated whether injection behaviour is differentially related to neighbourhood socioeconomic characteristics for IDUs in inner city vs. surrounding urban areas. Methods The study population was 468 active IDUs on the Island of Montréal. Neighbourhoods were represented as 500 m radius buffers around individual IDU dwelling places. High-risk injection behaviour (HRIB) was defined dichotomously. Relations between neighbourhood socioeconomic disadvantage (percentage households below low-income cutoff), neighbourhood educational attainment (percentage adults with university degree), and HRIB were assessed using multivariate logistic regression. Stratified analyses were conducted for inner city IDUs ( n = 219), and those in surrounding areas ( n = 249). Results Similar proportions of IDUs in inner city and surrounding areas reported HRIB. Neighbourhood socioeconomic characteristics were not associated with HRIB for IDUs in surrounding areas. For inner city IDUs, those in socioeconomically disadvantaged neighbourhoods were more likely to practice HRIB (OR 4.34; 95% CI 1.15–16.35). Conversely, inner city IDUs residing in lower educational attainment neighbourhoods had a lower odds of HRIB (OR 0.41; 95% CI 0.21–0.80). Conclusion HRIB did not vary according to urban environment but for inner-city IDUs was differentially related to socioeconomic markers. Associations between HRIB and neighbourhood socioeconomic disadvantage and lower educational attainment, positive and negative, respectively, indicate that adverse socioeconomic circumstances are not related to a uniformly greater likelihood of HRIB.

Predictors of Sharing Injection Equipment by HIV-Seropositive Injection Drug Users

Among HIV-positive injection drug users (IDUs), we examined baseline predictors of lending needles and syringes and sharing cookers, cotton, and rinse water in the prior 3 months at follow-up. Participants were enrolled in Intervention for Seropositive Injectors-Research and Evaluation, a secondary prevention intervention for sexually active HIV-positive IDUs in 4 US cities during 2001-2005. The analyses involved 357 participants who reported injecting drugs in the prior 6 months at either the 6- or 12-month follow-up visit. About half (49%) reported at least 1 sharing episode. In adjusted analyses, peer norms supporting safer injection practices and having primary HIV medical care visits in the prior 6 months were associated with reporting no sharing of injection equipment. Higher levels of psychological distress were associated with a greater likelihood of reporting drug paraphernalia sharing. These findings suggest that intervention approaches for reducing HIV-seropositive IDUs' transmission of blood-borne infections should include peer-focused interventions to alter norms of drug paraphernalia sharing and promoting primary HIV care and mental health services.

Social injecting and other correlates of high-risk sexual activity among injecting drug users in northern Vietnam

Background Sexual risk and STDs are relatively high among injecting drug users (IDUs) in Vietnam. We sought to determine characteristics of sexually active IDUs and correlates of high-risk sexual practices among IDUs in Bac Ninh province in northern Vietnam. Methods We used data collected for a community-based cross-sectional pilot study to identify correlates of recent high-risk sex (>1 sex partner and inconsistent/no condom use in the past year). Factors associated with high-risk sex were identified using logistic regression. Results Among 216 sexually active male IDUs, one third ( n = 72) had engaged in high-risk sex within the last year. IDUs who reported injecting with others more frequently, having someone else inject their drugs at last injection, sharing needles or sharing any injection equipment were more likely to have reported recent high-risk sex. Factors independently associated with high-risk sexual activity were not injecting oneself [AOR: 2.22; 95% CI (1.09–4.51)], and sharing needles in the past 12 months [AOR: 2.57; 95% CI (1.10–5.99)]. Conclusions IDUs who inject socially and IDUs who share needles are likely to engage in high-risk sexual behaviours and may serve as an important bridge group for epidemic HIV transmission in Vietnam. In addition to messages regarding the dangers of sharing needles and other injection equipment, preventive interventions among newly initiated IDUs should also focus on reducing sexual risk.