Patterns of and Rationale for the Co-use of Methamphetamine and Opioids: Findings From Qualitative Interviews in New Mexico and Nevada.

Introduction: Methamphetamine use and methamphetamine-involved deaths have increased dramatically since 2015, and opioid-related deaths now frequently involve methamphetamine. Nevada and New Mexico are states with elevated rates of opioid and methamphetamine use. In this paper, we report results from a qualitative analysis that examined patterns of methamphetamine and opioid co-use over participants' lifespan, factors that influence those patterns, and implications for health outcomes among users. Methods: Project AMPED was a multisite, mixed-methods study of methamphetamine use in Northern New Mexico and Northern Nevada. Between December 2019 and May 2020, qualitative interview participants were asked to describe their patterns of and reasons for co-administration of opioids and methamphetamine. Results: We interviewed 21 people who reported using methamphetamine in the past 3 months. Four primary patterns of methamphetamine and opioid co-use were identified: [1] using both methamphetamine and heroin, either simultaneously or sequentially (n = 12), [2] using methamphetamine along with methadone (n = 4), [3] using prescription opioids and methamphetamine (n = 1), and [4] using only methamphetamine (n = 4). Among those who used methamphetamine and heroin simultaneously or sequentially, motivations drew from a desire to enhance the effect of one drug or another, to feel the "up and down" of the "perfect ratio" of a goofball, or to mitigate unwanted effects of one or the other. Among those who used methamphetamine and methadone, motivations focused on alleviating the sedative effects of methadone. Conclusion: To address the emergent trend of increasing methamphetamine-related deaths, researchers, health care professionals, and community health workers must acknowledge the decision-making processes behind co-use of opioids and methamphetamine, including the perceived benefits and harms of co-use. There is an urgent need to address underlying issues associated with drug use-related harms, and to design interventions and models of treatment that holistically address participants' concerns.

Predictors of injecting cessation among a cohort of people who inject drugs in Tijuana, Mexico.

INTRODUCTION: Little is known about the cessation of injecting drug use (IDU) among people who inject drugs (PWID) in low and middle-income settings, where access to effective interventions for reducing drug use (e.g., opioid substitution treatment; OST), may be limited. We measured the incidence and identified predictors of IDU cessation among a cohort of PWID in Tijuana, Mexico. METHODS: Data were drawn from 621 participants in Proyecto El Cuete IV, a prospective cohort of PWID recruited in 2011 and interviewed biannually to 2016. A multivariable Extended Cox model was constructed to identify socio-demographic, drug use, risk environment and health-related predictors of IDU cessation (no IDU for ≥six months). RESULTS: 141 participants (23%) reported at least one IDU cessation event during follow-up. The crude IDU cessation rate was 7.3 per 100 person-years (95% Confidence Interval [CI]: 6.2-8.7). IDU cessation was negatively associated with injecting at least daily on average and heroin/methamphetamine co-injection in the past six months, and positively associated with testing HIV positive at baseline, being on methadone maintenance therapy in the past six months, and recent arrest. Concern for personal safety was also independently associated with IDU cessation. CONCLUSIONS: The rate of IDU cessation among PWID in Tijuana was low. These findings underscore the importance of expansion of services including OST to help reduce drug use and facilitate IDU cessation for those who wish to do so. In this setting, interventions addressing individual-level economic barriers as well as broader social and structural barriers to harm reduction services are integral.

Mental health of heroin users with differing injection drug use histories: A non-treatment sample of Mexican American young adult men.

BACKGROUND: While the comorbidity of mental health and injecting heroin has been documented, current research is limited by describing the mental health of people who inject drugs without a comparison group and by the lack of research on nontreatment samples in the United States, particularly among Hispanics. The purpose of this study was to examine the association of injecting history (never, former, occasional, and daily) and multiple outcomes of global and mental health using a sample of U.S.-based Latinos not currently in treatment. METHODS: Data are from a sample of street-recruited Mexican American young adult men (n=275) in San Antonio, TX. Multiple logistic regression and structural equation modeling were used. RESULTS: Overall 54% of men reported lifetime injecting drug use (20.7% former users, 11.1% occasional users, and 21.9% daily users). We found varying prevalence rates of global and mental health status among different histories of injecting. After covariate adjustment, daily injecting remained strongly associated with all four outcomes: perceived poor health status (AOR=4.39; p≤0.001), psychological distress (AOR=2.78; p≤0.05), depression (AOR=4.37; p≤0.001), and suicidal ideation (OR=4.75; p≤0.001). Acculturation, gang membership, and incarceration history also emerged as important factors. CONCLUSION: This study provides new information about the relationship between mental health and injecting heroin use. FINDINGS: Support the need to consider mental health states among people who inject drugs, and to examine varying histories of injecting with socially and culturally relevant factors.

Injecting Drug Use Among Mexican Female Sex Workers on the US-Mexico Border.

Both injecting drug users (IDU) and sex workers are at great risk of contracting and transmitting HIV. Therefore, IDU sex workers could be at especially high risk. The recent increase of HIV infection in Mexico has caused increased attention to sex work. We identify the correlates of injecting drug use including socio-demographic, work history, and sexual and non-injecting drug use risk behaviors among Mexican female sex workers. There is a high risk profile for IDUs compared to never injectors including a high prevalence of lifetime STI infection (54.2%). Revealed is an environment composed of high-risk networks that may have serious binational public health implications.

Prevalence and correlates of neck injection among people who inject drugs in Tijuana, Mexico.

INTRODUCTION AND AIMS: Injecting drugs in the neck has been related to adverse health conditions such as jugular vein thrombosis, deep neck infections, aneurysm, haematomas, airway obstruction, vocal cord paralysis and wound botulism, among others. We identified prevalence and correlates of neck injection among people who inject drugs (PWID) in Tijuana, Mexico. DESIGN AND METHODS: Beginning in 2011, PWID aged ≥18 years who injected drugs within the last month were recruited into a prospective cohort. At baseline and semi-annually, PWID completed interviewer-administered surveys soliciting data on drug-injecting practices. Logistic regression was used to identify predictors of injecting in the neck as the most frequent injection site at a single visit. RESULTS: Of 380 PWID, 35.3% injected in the neck at least once in the past 6 months, among whom 71.6% reported it as their most common injection site, the most common injecting site after the arms (47%). Controlling for age, years injecting and injecting frequency, injecting heroin and methamphetamine two or more times per day and having sought injection assistance were associated with injecting in the neck [adjusted odds ratios (AOR): 2.12; 95% confidence intervals (CI): 1.27-3.53 and AOR: 2.65; 95% CI: 1.52-4.53 respectively]. DISCUSSION AND CONCLUSIONS: Injecting in the neck was very common among PWID in Tijuana and was associated with polydrug use and seeking injection assistance. Tailoring harm reduction education interventions for individuals who provide injection assistance ('hit doctors') may allow for the dissemination of safe injecting knowledge to reduce injection-related morbidity and mortality.

Incident syphilis infection among people who inject drugs in Tijuana, Mexico.

Given that syphilis is associated with HIV infection among people who inject drugs (PWID), we examined syphilis incidence among PWID in Tijuana, Mexico. From 2006 to 2007, 940 PWID (142 women and 798 men) were recruited via respondent-driven sampling and followed for 18 months. At semi-annual visits, participants were tested for syphilis and completed surveys, which collected information on socio-demographics, sexual behaviours, substance use and injection behaviours. Poisson regression was used to estimate syphilis incidence rates (IRs), incidence rate ratios (IRRs) and 95% confidence intervals (CIs). Twenty-one participants acquired syphilis during follow-up (IR = 1.57 per 100 person-years, 95% CI: 1.02-2.41). In a multivariate analysis, syphilis incidence was higher among women (IRR = 3.90, 95% CI: 1.37-11.09), HIV-positive participants (IRR = 4.60, 95% CI: 1.58-13.39) and those who reported ever exchanging sex for drugs, money, or other goods (IRR = 2.74, 95% CI: 0.97-7.76), while syphilis incidence was lower among those living in Tijuana for a longer duration (IRR = 0.95 per year, 95% CI: 0.91-1.00) and those reporting at least daily injection drug use (past 6 months) (IRR = 0.22, 95% CI: 0.09-0.54). Our findings suggest interventions that address the destabilising conditions associated with migration and integrate sexual and drug-related risk reduction strategies may help reduce syphilis incidence among PWID along the Mexico-US border.