Regional differences between people who inject drugs in an HIV prevention trial integrating treatment and prevention (HPTN 074): a baseline analysis

INTRODUCTION

People who inject drugs (PWID) experience high HIV incidence and face significant barriers to engagement in HIV care and substance use treatment. Strategies for HIV treatment as prevention and substance use treatment present unique challenges in PWID that may vary regionally. Understanding differences in the risk structure for HIV transmission and disease progression among PWID is essential in developing and effectively targeting intervention strategies of HIV treatment as prevention.

METHODS

We present a baseline analysis of HIV Prevention Trials Network (HPTN) 074, a two-arm, randomized controlled trial among PWID in Indonesia (n = 258), Ukraine (n = 457) and Vietnam (n = 439). HPTN 074 was designed to determine the feasibility, barriers and uptake of an integrated intervention combining health systems navigation and psychosocial counselling for the early engagement of antiretroviral therapy (ART) and substance use treatment for PWID living with HIV. Discordant PWID networks were enrolled, consisting of an HIV-positive index and their HIV-negative network injection partner(s). Among the enrolled cohort of 1154 participants (502 index participants and 652 network partners), we examine regional differences in the baseline risk structure, including sociodemographics, HIV and substance use treatment history, and injection and sexual risk behaviours.

RESULTS

The majority of participants were male (87%), with 82% of the enrolled females coming from Ukraine. The overall mean age was 34 (IQR: 30, 38). Most commonly injected substances included illegally manufactured methadone in Ukraine (84.2%), and heroin in Indonesia (81.8%) and Vietnam (99.5%). Injection network sizes varied by region: median number of people with whom participants self-reported injecting drugs was 3 (IQR: 2, 5) in Indonesia, 5 (IQR: 3, 10) in Ukraine and 3 (IQR: 2, 4) in Vietnam. Hazardous alcohol use, assessed using the Alcohol Use Disorders Identification Test - Alcohol Consumption Questions (AUDIT-C), was prominent in Ukraine (54.7%) and Vietnam (26.4%). Reported sexual risk behaviours in the past month, including having two or more sex partners and giving/receiving money or drugs in exchange for sex, were uncommon among all participants and regions.

CONCLUSIONS

While regional differences in risk structure exist, PWID particularly in Ukraine need immediate attention for risk reduction strategies. Substantial regional differences in risk structure will require flexible, tailored treatment as prevention interventions for distinct PWID populations.

Feasibility and utility of momentary sampling of sex events in young couples

Research on couples' sexual behaviors is limited because most studies collect data from only one person, rely on retrospective recall, and lack ecological validity. This study explored the feasibility of using momentary sampling (MS) methods to collect sex event data from both members of heterosexual young adult couples. Over two weeks, 40 participants (20 couples) were asked to use a handheld computer to respond to random auditory signals each day and self-initiate a report as soon as possible after sex. Couples were randomized into two groups: (a) both partners reported after sex events, or (b) one partner reported after sex events during Week 1 and the other during Week 2 (randomized by gender). Descriptive statistics examined protocol compliance, partner agreement on whether an event occurred, condom use, and reason for sex, as well as partner involvement in reporting, comfort with reporting after sex, and study burden. Results indicated that couples were willing and able to adhere to the protocol. Partners agreed on condom use for nearly all sex events, but frequently reported different reasons for sex events. The use of MS methods to collect information about sex events within couples is a promising approach to the study of sexual behavior.