Evaluation of respondent-driven sampling in seven studies of people who use drugs from rural populations: findings from the Rural Opioid Initiative.

BACKGROUND: Accurate prevalence estimates of drug use and its harms are important to characterize burden and develop interventions to reduce negative health outcomes and disparities. Lack of a sampling frame for marginalized/stigmatized populations, including persons who use drugs (PWUD) in rural settings, makes this challenging. Respondent-driven sampling (RDS) is frequently used to recruit PWUD. However, the validity of RDS-generated population-level prevalence estimates relies on assumptions that should be evaluated. METHODS: RDS was used to recruit PWUD across seven Rural Opioid Initiative studies between 2018-2020. To evaluate RDS assumptions, we computed recruitment homophily and design effects, generated convergence and bottleneck plots, and tested for recruitment and degree differences. We compared sample proportions with three RDS-adjusted estimators (two variations of RDS-I and RDS-II) for five variables of interest (past 30-day use of heroin, fentanyl, and methamphetamine; past 6-month homelessness; and being positive for hepatitis C virus (HCV) antibody) using linear regression with robust confidence intervals. We compared regression estimates for the associations between HCV positive antibody status and (a) heroin use, (b) fentanyl use, and (c) age using RDS-1 and RDS-II probability weights and no weights using logistic and modified Poisson regression and random-effects meta-analyses. RESULTS: Among 2,842 PWUD, median age was 34 years and 43% were female. Most participants (54%) reported opioids as their drug of choice, however regional differences were present (e.g., methamphetamine range: 4-52%). Many recruitment chains were not long enough to achieve sample equilibrium. Recruitment homophily was present for some variables. Differences with respect to recruitment and degree varied across studies. Prevalence estimates varied only slightly with different RDS weighting approaches, most confidence intervals overlapped. Variations in measures of association varied little based on weighting approach. CONCLUSIONS: RDS was a useful recruitment tool for PWUD in rural settings. However, several violations of key RDS assumptions were observed which slightly impacts estimation of proportion although not associations.

The relationship between felt stigma and non-fatal overdose among rural people who use drugs.

BACKGROUND: Drug overdose deaths in the United States exceeded 100,000 in 2021 and 2022. Substance use stigma is a major barrier to treatment and harm reduction utilization and is a priority target in ending the overdose epidemic. However, little is known about the relationship between stigma and overdose, especially in rural areas. We aimed to characterize the association between felt stigma and non-fatal overdose in a multi-state sample of rural-dwelling people who use drugs. METHODS: Between January 2018 and March 2020, 2,608 people reporting past 30-day opioid use were recruited via modified chain-referral sampling in rural areas across 10 states. Participants completed a computer-assisted survey of substance use and substance-related attitudes, behaviors, and experiences. We used multivariable logistic regression with generalized estimating equations to test the association between felt stigma and recent non-fatal overdose. RESULTS: 6.6% of participants (n = 173) reported an overdose in the past 30 days. Recent non-fatal overdose was significantly associated with felt stigma after adjusting for demographic and substance use-related covariates (aOR: 1.47, 95% CI: 1.20-1.81). The association remained significant in sensitivity analyses on component fear of enacted stigma items (aOR: 1.48, 95% CI: 1.20-1.83) and an internalized stigma item (aOR: 1.51, 95% CI: 1.07-2.14). CONCLUSIONS: Felt stigma related to substance use is associated with higher risk of non-fatal overdose in rural-dwelling people who use drugs. Stigma reduction interventions and tailored services for those experiencing high stigma are underutilized approaches that may mitigate overdose risk.

Differences in internalized HIV stigma across subpopulations of people with HIV in care across the United States.

BACKGROUND: Few studies have examined which subgroups of people with HIV (PWH) carry the greatest burden of internalized HIV stigma (IHS), which may be important to care provision and interventions. METHODS: PWH in the CFAR Network of Integrated Clinical Systems (CNICS) longitudinal, US-based, multisite, clinical care cohort completed tablet-based assessments during clinic visits including a four-item, Likert scale (low 1-5 high), IHS instrument. Associations between sociodemographic characteristics and IHS scores were assessed in adjusted linear regression models. RESULTS: Twelve thousand six hundred and fifty-six PWH completed the IHS assessment at least once from February 2016 to November 2022, providing 28 559 IHS assessments. At baseline IHS assessment, the mean age was 49 years, 41% reported White, 38% Black/African American, and 16% Latine race/ethnicity, and 80% were cisgender men. The mean IHS score was 2.04, with all subgroups represented among those endorsing IHS. In regression analyses, younger PWH and those in care fewer years had higher IHS scores. In addition, cisgender women vs. cisgender men, PWH residing in the West vs. the Southeast, and those with sexual identities other than gay/lesbian had higher IHS scores. Compared with White-identifying PWH, those who identified with Black/African American or Latine race/ethnicity had lower IHS scores. Age stratification revealed patterns related to age category, including specific age-related differences by gender, geographic region and race/ethnicity. DISCUSSION: IHS is prevalent among PWH, with differential burden by subgroups of PWH. These findings highlight the benefits of routine screening for IHS and suggest the need for targeting/tailoring interventions to reduce IHS among PWH.

Behavioral and Health Outcome Differences by Heroin or Methamphetamine Preference Among People in Rural US Communities Who Use Both Substances.

Background: The United States' (US) opioid overdose epidemic has evolved into a combined stimulant/opioid epidemic, a pattern driven in part by mitigating opioid overdose risk, variable substance availability, and personal preferences. This study aimed to investigate the association between self-reported substance preference (heroin or methamphetamine) and behavioral/health outcomes among individuals who used both heroin and methamphetamine in the rural US. Methods: The Rural Opioid Initiative is a consortium of 8 research cohorts from 10 states and 65 rural counties that recruited individuals reporting past 30-day injection of any substance or opioid substance use by any route from 1/2018 to 3/2020. Analyses were restricted to participants ⩾18 years, who self-reported either heroin or methamphetamine as their preferred substance and past 30-day use of both heroin and methamphetamine. We examined cross-sectional associations between preferred substance (heroin versus methamphetamine) and behavioral and health outcomes using random effects meta-analysis with adjusted regression models. Results: Among 1239 participants, 61% (n = 752) reported heroin as their preferred substance. Adjusting for age, sex, and race/ethnicity, methamphetamine preference was associated with lower prevalence ratios for current naloxone possession (adjusted prevalence ratio [aPR] = 0.68; 95% Confidence Interval [95% CI] = 0.59-0.78; P-value ⩽ .001), of ever being told they had the hepatitis C virus (HCV; aPR = 0.72; 95% CI: 0.61-0.85; P-value ⩽ .001) and a personal history of overdose (aPR = 0.81; 95% CI = 0.73-0.90; P-value ⩽ .001). Conclusion: In our study analyzing associations between preferred substance and various behavioral and health outcomes amongst people who use both heroin and methamphetamine, a majority of participants preferred heroin. Methamphetamine preference was associated with lower prevalence of naloxone possession, ever being told they had HCV, and prior history of an overdose. This study underscores the need for targeted harm reduction services for people who prefer methamphetamine in rural areas.

Evaluating the Sick Quitting Hypothesis for Frailty Status and Reducing Alcohol Use Among People With HIV in a Longitudinal Clinical Cohort Study.

ABSTRACT: "Sick quitting," a phenomenon describing reductions in alcohol consumption following poor health, may explain observations that alcohol appears protective for frailty risk. We examined associations between frailty and reductions in drinking frequency among people with HIV (PWH). At six Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) sites between January 2012 and August 2021, we assessed whether frailty, measured through validated modified frailty phenotype, precedes reductions in drinking frequency. We associated time-updated frailty with quitting and reducing frequency of any drinking and heavy episodic drinking (HED), adjusted for demographic and clinical characteristics in Cox models. Among 5,654 PWH reporting drinking, 60% reported >monthly drinking and 18% reported ≥monthly HED. Over an average of 5.4 years, frail PWH had greater probabilities of quitting (HR: 1.56, 95% confidence interval [95% CI] [1.13-2.15]) and reducing (HR: 1.35, 95% CI [1.13-1.62]) drinking frequency, as well as reducing HED frequency (HR: 1.58, 95% CI [1.20-2.09]) versus robust PWH. Sick quitting likely confounds the association between alcohol use and frailty risk, requiring investigation for control.