Correlates of injecting in an HIV incidence hotspot among substance users in Tijuana, Mexico

WaSH insecurity and anxiety among people who inject drugs in the Tijuana-San Diego border region

BACKGROUND

Water, sanitation, and hygiene (WaSH) insecurity increases the risk of water-related diseases. However, limited research has been conducted on psychosocial distress as it relates to WaSH insecurity, especially among people who inject drugs (PWID). We examined the relationship between WaSH insecurity and related anxiety among PWID living in different housing conditions along the US-Mexico border region.

METHODS

From 2020-2021, a cross-sectional study was conducted among 585 people who injected drugs within the last month in Tijuana (N = 202), San Diego (N = 182), and in both Tijuana and San Diego (N = 201). Participants underwent interviewer-administered surveys related to WaSH access, substance use, and generalized anxiety disorder (GAD-7). Quasi-Poisson regressions were used to assess associations between WaSH insecurity and anxiety in the prior 6-months.

RESULTS

Participants were 75% male, 42% were unhoused and 91% experienced WaSH insecurity in the prior 6-months. After adjusting for housing status, gender, and age, lack of access to basic drinking water (Adj RR: 1.28; 95% CI: 1.02-1.58), sanitation (Adj RR:1.28; 95% CI: 1.07-1.55), and a daily bath/shower (Adj RR: 1.38; 95% CI: 1.15-1.66) were associated with mild-severe anxiety. The number of WaSH insecurities was independently associated with a 20% increased risk of experiencing anxiety per every additional insecurity experienced (Adj RR: 1.20; CI: 1.12-1.27). We also found a significant interaction between gender and housing status (p = 0.003), indicating that among people experiencing sheltered/unsheltered homelessness, women had a higher risk of mild-severe anxiety compared to men (Adj RR: 1.55; 95% CI: 1.27-1.89). At the same time, among women, those who are unhoused have 37% increased risk of anxiety than those who live in stable housing conditions (Adj RR: 1.37; 95% CI: 1.01-1.89).

CONCLUSION

The lack of specific WaSH services, particularly lack of drinking water, toilets, and daily showers were associated with higher levels of anxiety among PWID in the Tijuana-San Diego border region. Women experiencing homelessness were especially vulnerable. WaSH interventions that provide safe, 24-h access may help to reduce anxiety and health risks associated with WaSH insecurity.

Latent polydrug use patterns and the provision of injection initiation assistance among people who inject drugs in three North American settings

INTRODUCTION

We sought to identify latent profiles of polysubstance use patterns among people who inject drugs in three distinct North American settings, and then determine whether profile membership was associated with providing injection initiation assistance to injection-naïve persons.

METHODS

Cross-sectional data from three linked cohorts in Vancouver, Canada; Tijuana, Mexico; and San Diego, USA were used to conduct separate latent profile analyses based on recent (i.e., past 6 months) injection and non-injection drug use frequency. We then assessed the association between polysubstance use patterns and recent injection initiation assistance provision using logistic regression analyses.

RESULTS

A 6-class model for Vancouver participants, a 4-class model for Tijuana participants and a 4-class model for San Diego participants were selected based on statistical indices of fit and interpretability. In all settings, at least one profile included high-frequency polysubstance use of crystal methamphetamine and heroin. In Vancouver, several profiles were associated with a greater likelihood of providing recent injection initiation assistance compared to the referent profile (low-frequency use of all drugs) in unadjusted and adjusted analyses, however, the inclusion of latent profile membership in the multivariable model did not significantly improve model fit.

DISCUSSION AND CONCLUSIONS

We identified commonalities and differences in polysubstance use patterns among people who inject drugs in three settings disproportionately impacted by injection drug use. Our results also suggest that other factors may be of greater priority when tailoring interventions to reduce the incidence of injection initiation. These findings can aid in efforts to identify and support specific higher-risk subpopulations of people who inject drugs.

HIV and Substance Use in Latin America: A Scoping Review

This scoping review aims to explore the interplay between substance use (SU) and HIV in Latin America (LA). Database searches yielded 3481 references; 196 were included. HIV prevalence among people who used substances (PWUS) ranged from 2.8–15.2%. SU definitions were variable throughout studies, and thus data were not easily comparable. In 2019, only 2% of new HIV infections were attributed to injection drug use (IDU) in LA. Factors associated with HIV among PWUS included being female, IDU and homelessness, and PWUS were likely to engage in risky sexual behaviors, start antiretroviral treatment late, have poor adherence, have treatment failure, be lost to follow-up, have comorbidities, and experience higher mortality rates and lower quality of life, as has been reported in PLWH with SU in other regions. Five intervention studies were identified, and only one was effective at reducing HIV incidence in PWUS. Interventions in other regions have varying success depending on context-specific characteristics, highlighting the need to conduct more research in the LA region. Though progress has been made in establishing SU as a major concern in people living with HIV (PLWH), much more is yet to be done to reduce the burden of HIV and SU in LA.

Drugs, discipline and death: Causes and predictors of mortality among people who inject drugs in Tijuana, 2011-2018

BACKGROUND

People who inject drugs (PWID) experience multiple risk factors for mortality; yet, we know little about causes of death among PWID in Tijuana, Mexico, an area with high levels of injecting and changes in policy/law enforcement responses to substance use. This study examines rates, causes, and predictors of mortality among Tijuana PWID.

METHODS

Data come from a community-based cohort of PWID aged ≥18 who injected drugs in the past month. Mortality was confirmed by death certificate over 78 months during 2011-2018. Predictors of mortality were identified using time-updated Cox regression, controlling for age.

RESULTS

Among 734 participants, there were 130 deaths (54 confirmed, 76 unconfirmed), with an incidence rate of 17.74 deaths per 1000 person-years for confirmed deaths (95% Confidence Interval (CI)=13.01, 22.48) and 39.52 for unconfirmed deaths (CI=32.72, 46.31). Confirmed deaths resulted from homicide/trauma (26%), overdose (26%), septic shock (18%) and HIV-related causes (9%). In multivariable analysis of confirmed deaths, baseline HIV seropositivity (adjusted Hazard Ratio [aHR]=6.77, CI=1.98, 23.17), incident HIV infection (aHR=3.19, CI=1.02, 9.96), and number of times being beaten by police in the past 6 months at baseline (aHR=1.08 per time, CI=1.04, 1.12) were predictive of death; whereas, injection cessation for 6+ months during time at risk (aHR=0.25, CI=0.33, 0.79) was protective.

CONCLUSION

In addition to overdose and HIV prevention efforts, attention to structural conditions that potentiate mortality is needed, including improved access to medication-assisted treatment to support injection cessation and a shift from police as a source of harm to harm reduction.

Injection Drug Use Trajectories among Migrant Populations: A Narrative Review

BACKGROUND

Dual epidemics of injection drug use and blood-borne disease, characterized as "syndemics," are present in a range of settings. Behaviors that drive such syndemics are particularly prevalent among mobile drug-using populations, for whom cross-border migration may pose additional risks.

OBJECTIVES

This narrative review aims to characterize the risk factors for injection drug use initiation associated with migration, employing a risk environment framework and focusing on the San Diego-Tijuana border region as the most dynamic example of these phenomena.

METHODS

Based on previous literature, we divide migration streams into three classes: intra-urban, internal, and international. We synthesized existing literature on migration and drug use to characterize how mobility and migration drive the initiation of injection drug use, as well as the transmission of hepatitis and HIV, and to delineate how these might be addressed through public health intervention.

RESULTS

Population mixing between migrants and receiving communities and the consequent transmission of social norms about injection drug use create risk environments for injection drug use initiation. These risk environments have been characterized as a result of local policy environments, injection drug use norms in receiving communities, migration-related stressors, social dislocation, and infringement on the rights of undocumented migrants.

CONCLUSION

Policies that exacerbate risk environments for migrants may inadvertently contribute to the expansion of epidemics of injection-driven blood-borne disease. Successful interventions that address emerging syndemics in border regions may therefore need to be tailored to migrant populations and distinguish between the vulnerabilities experienced by different migration classes and border settings.

HIV Prevalence, Knowledge, Attitudes, and Practices Among Polydrug Users in Brazil: A Biological Survey Using Respondent Driven Sampling

Brazil has a concentrated HIV epidemic among key populations. In 2009, the Ministry of Health conducted a survey in 10 Brazilian cities aiming to estimate HIV prevalence, knowledge, and associated risk behaviors of polysubstance users (PSU). Using Respondent Driven Sampling (RDS), 3449 PSU were recruited, answered an Audio-Computer Self Assisted Interview (ACASI) and were tested for HIV and syphilis. Analyses were weighted by individual's social network size generated on RDSAT. Pooled HIV prevalence was 5.8% but varied across cities. Most PSU were male, non-white, without income, unemployed, with low levels of education. Overall, 12.0% used injectable drugs, 48.7% had sex with occasional partners and 46.4% engaged in commercial sex. A majority received free condoms (71.4%) but 76.7% exhibited inconsistent condom use. Findings can support policies aiming to improve health care and preventive interventions tailored to this population that remains at high risk of acquiring and transmitting HIV/STI in multiple scenarios.

Assessing police officers' attitudes and legal knowledge on behaviors that impact HIV transmission among people who inject drugs

BACKGROUND

Policing practices such as syringe confiscation and arrest can act as important social-structural drivers of HIV risk among people who inject drugs (PWID). However, police referral to treatment and other services may improve the health of PWID. Little is known about the role of modifiable attitudinal and knowledge factors in shaping officer behavior. Using baseline findings from a police education program (PEP), we assessed relationships between drug policy knowledge and attitudes towards public health interventions with self-reported syringe confiscation, drug arrest, and service referral among street-level police in Tijuana, Mexico.

METHODS

Between February, 2015 and May, 2016 we surveyed 1319 police officers who reported syringe contact. The self-administered survey focused on attitudes, knowledge, and behaviors related to drug policy, public health, and occupational safety. We used ordinal logistic regression to model the odds of syringe confiscation, arrest for heroin possession, and referring PWID to health/social programs.

RESULTS

The sample was mostly male (87%) and had at least a high school education (80%). In the last six months, a minority reported always/sometimes confiscating syringes (49%), arresting someone for heroin possession (43%), and referring PWID to health and social programs (37%). Those reporting needlestick injuries (NSI) had 1.38 (95% CI: 1.02-1.87) higher odds of reporting syringe confiscation. Officers who had favorable views on laws that treat addiction as a public health issue had lower odds (aOR=0.78; 95% CI: 0.59-1.03) of arresting PWID. Those agreeing that it was their role to refer PWID to health and social programs had higher odds of reporting such referrals (aOR: 3.32, 95% CI: 2.52-4.37). Legal knowledge was not associated with these practices.

CONCLUSION

Changing drug policy and knowledge may be insufficient in shifting police behavior. Modifying officers' occupational risks and attitudes towards harm reduction interventions can facilitate efforts to align police practices with PWID health.

A socio-structural approach to preventing injection drug use initiation: rationale for the PRIMER study

BACKGROUND

Injection drug use remains a primary driver of HIV and HCV-related harms globally. However, there is a gap in efforts to prevent individuals from transitioning into injecting. People who inject drugs (PWID) play a key role in the transition of others into injecting, and while behavioral interventions have been developed to address this phenomenon, socio-structural approaches remain unexplored. To that end, we hypothesize that certain interventions designed to reduce injecting-related risk behaviors may also reduce the risk that PWID expose and introduce others into injecting. Identifying the preventive potential of existing interventions will inform broader efforts to prevent injecting and related harms.

METHODS

The Preventing Injecting by Modifying Existing Responses (PRIMER) study is a multi-country mixed methods study with an aim to investigate whether specific interventions (e.g., opioid substitution therapy, supervised injection facilities, stable housing, incarceration environments) and related factors (e.g., public injecting and gender) influence the likelihood that PWID initiate others into injecting. This study will (1) investigate the PWID participation in injection initiation; (2) identify factors influencing the risk that PWID expose others to or facilitate injection initiation; (3) describe drug scene roles that increase the risk of PWID facilitating injection initiation; and (4) evaluate the impact of structural, social, or biomedical interventions on the risk that PWID facilitate injection initiation. It does so by pooling observational data from cohort studies of PWID in six cities: Vancouver, Canada; San Diego, USA; Tijuana, Mexico; Paris, Marseille, and Bordeaux, France.

RESULTS

Team members are conducting a prospective, multi-site study of PWID (n = 3050) in North America and France that includes quantitative and qualitative data collection through four separate cohort studies of PWID (San Diego, STAHR II; Tijuana, El Cuete IV; Vancouver, V-DUS; Bordeaux, Marseille, Paris and Strasbourg, COSINUS).

CONCLUSIONS

PRIMER is the largest study of injection initiation to date and the first to investigate structural approaches to preventing injection drug use initiation. Findings have the potential to inform the development and scale up of new and existing interventions to prevent transitions into injecting.

TRIAL REGISTRATION

Preventing Injecting by Modifying Existing Responses (PRIMER), NIDA DP2-DA040256-01 .

Prevalence and correlates of needle-stick injuries among active duty police officers in Tijuana, Mexico

Introduction

Police officers are at an elevated risk for needle-stick injuries (NSI), which pose a serious and costly occupational health risk for HIV and viral hepatitis. However, research on NSIs among police officers is limited, especially in low- and middle-income countries. Despite the legality of syringe possession in Mexico, half of people who inject drugs (PWID) in Tijuana report extrajudicial syringe-related arrests and confiscation by police, which has been associated with needle-sharing and HIV infection. We assessed the prevalence and correlates of NSIs among Tijuana police officers to inform efforts to improve occupational safety and simultaneously reduce HIV risks among police and PWID.

Methods

Tijuana's Department of Municipal Public Safety (SSPM) is among Mexico's largest. Our binational, multi-sectoral team analyzed de-identified data from SSPM's 2014 anonymous self-administered occupational health survey. The prevalence of NSI and syringe disposal practices was determined. Logistic regression with robust variance estimation via generalized estimating equations identified factors associated with ever having an occupational NSI.

Results

Approximately one-quarter of the Tijuana police force was given the occupational health survey (N=503). Respondents were predominantly male (86.5%) and ≤35 years old (42.6%). Nearly one in six officers reported ever having a NSI while working at SSPM (15.3%), of whom 14.3% reported a NSI within the past year. Most participants reported encountering needles/syringes while on duty (n=473, 94%); factors independently associated with elevated odds of NSIs included frequently finding syringes that contain drugs (adjusted odds ratio (AOR): 2.98; 95% confidence interval (CI): 1.56–5.67) and breaking used needles (AOR: 2.25; 95% CI: 1.29–3.91), while protective factors included being willing to contact emergency services in case of NSIs (AOR: 0.39; 95% CI: 0.22–0.69), and wearing needle-stick resistant gloves (AOR: 0.43; 95% CI: 0.19–0.91).

Conclusions

Tijuana police face an elevated and unaddressed occupational NSI burden associated with unsafe syringe-handling practices, exposing them to substantial risk of HIV and other blood-borne infections. These findings spurred the development and tailoring of training to reduce NSI by modifying officer knowledge, attitudes and enforcement practices (e.g. syringe confiscation) – factors that also impact HIV transmission among PWID and other members of the community.

Spatial patterns of arrests, police assault and addiction treatment center locations in Tijuana, Mexico

AIMS

In the context of a public health-oriented drug policy reform in Mexico, we assessed the spatial distribution of police encounters among people who inject drugs (PWID) in Tijuana, determined the association between these encounters and the location of addiction treatment centers and explored the association between police encounters and treatment access.

DESIGN

Geographically weighted regression (GWR) and logistic regression analysis using prospective spatial data from a community-recruited cohort of PWID in Tijuana and official geographical arrest data from the Tijuana Municipal Police Department.

SETTING

Tijuana, Mexico.

PARTICIPANTS

A total of 608 participants (median age 37; 28.4% female) in the prospective Proyecto El Cuete cohort study recruited between January and December 2011.

MEASUREMENTS

We compared the mean distance of police encounters and a randomly distributed set of events to treatment centers. GWR was undertaken to model the spatial relationship between police interactions and treatment centers. Logistic regression analysis was used to investigate factors associated with reporting police interactions.

FINDINGS

During the study period, 27.5% of police encounters occurred within 500 m of treatment centers. The GWR model suggested spatial correlation between encounters and treatment centers (global R(2)  = 0.53). Reporting a need for addiction treatment was associated with reporting arrest and police assault [adjusted odds ratio = 2.74, 95% confidence interval (CI) = 1.25-6.02, P = 0.012].

CONCLUSIONS

A geospatial analysis suggests that, in Mexico, people who inject drugs are at greater risk of being a victim of police violence if they consider themselves in need of addiction treatment, and their interactions with police appear to be more frequent around treatment centers.

The association between psychosocial and structural-level stressors and HIV injection drug risk behavior among Malaysian fishermen: A cross-sectional study

Background

Malaysian fishermen have been identified as a key-affected HIV population with HIV rates 10 times higher than national rates. A number of studies have identified that psychosocial and structural-level stressors increase HIV injection drug risk behaviors. The purpose of this paper is to examine psychosocial and structural-level stressors of injection drug use and HIV injection drug risk behaviors among Malaysian fishermen.

Methods

The study employs a cross-sectional design using respondent driven sampling methods. The sample includes 406 fishermen from Pahang state, Malaysia. Using multivariate logistic regressions, we examined the relationship between individual (depression), social (adverse interactions with the police), and structural (poverty-related) stressors and injection drug use and risky injection drug use (e.g.., receptive and non-receptive needle sharing, frontloading and back-loading, or sharing drugs from a common container).

Results

Participants below the poverty line had significantly lower odds of injection drug use (OR 0.52, 95 % CI: 0.27-0.99, p = 0.047) and risky injection drug use behavior (OR 0.48, 95 % CI: 0.25-0.93, p = 0.030). In addition, participants with an arrest history had higher odds of injection use (OR 19.58, 95 % CI: 9.81-39.10, p < 0.001) and risky injection drug use (OR 16.25, 95 % CI: 4.73-55.85, p < 0.001). Participants with depression had significantly higher odds of engaging in risky injection drug use behavior (OR 3.26, 95 % 1.39-7.67, p = 0.007). Focusing on participants with a history of injection drug use, we found that participants with depression were significantly more likely to engage in risky drug use compared to participants below the depression cutoff (OR 3.45, 95 % CI: 1.23-9.66, p < 0.02).

Conclusions

Findings underscore the need to address psychosocial and structural-level stressors among Malaysian fishermen to reduce HIV injection drug risk behaviors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3125-7) contains supplementary material, which is available to authorized users.

Institutional stakeholder perceptions of barriers to addiction treatment under Mexico's drug policy reform

Mexico has experienced disproportionate drug-related harms given its role as a production and transit zone for illegal drugs destined primarily for the USA. In response, in 2009, the Mexican federal government passed legislation mandating pre-arrest diversion of drug-dependent individuals towards addiction treatment. However, this federal law was not specific about how the scale-up of the addiction treatment sector was to be operationalised. We therefore conducted in-depth qualitative interviews with key 'interactors' in fields affected by the federal legislation, including participants from the law enforcement, public health, addiction treatment, and governmental administration sectors. Among 19 participants from the municipal, state and federal levels were interviewed and multiple barriers to policy reform were identified. First, there is a lack of institutional expertise to implement the reform. Second, the operationalisation of the reform was not accompanied by a coordinated action plan. Third, the law is an unfunded mandate. Institutional barriers are likely hampering the implementation of Mexico's policy reform. Addressing the concerns expressed by interactors through the scale-up of services, the provision of increased training and education programmes for stakeholders and a coordinated action plan to operationalise the policy reform are likely needed to improve the policy reform process.