Multilevel Influences on HIV and Substance Use in a YMSM Cohort (RADAR), Chicago Metropolitan Area, 2015-2020

The National Institute on Drug Abuse (NIDA) funded RADAR in 2014 to collect multilevel,
longitudinal data and biospecimens from an ethnically and racially diverse
cohort of young, sexual and gender minorities (SGM; e.g., men who have sex with
men (MSM), transgender women, gender non-conforming individuals) who were
assigned male at birth (AMAB) (current core cohort n=1,113). The primary
objective of this study is to apply a multilevel perspective to a syndemic of
health issues associated with human immunodeficiency virus (HIV) in this
population. The multilevel design focuses on individual, dyadic (i.e., sexual
and romantic relationships), network (i.e., social, drug, and sexual
connections) and biologic factors that may be associated with HIV. The cohort
contains both HIV-negative and HIV-positive individuals, which allows for the
development of a repository of biospecimens and HIV sequence data from both
pre-infection and post-infection visits that will help facilitate future
projects evaluating substance use, HIV risk, and pathogenesis.
A multiple cohort, accelerated longitudinal
design was utilized by initially enrolling two existing SGM cohorts and then
expanded through the use of convenience and snowball sampling methods.
Enrollment criteria varied slightly based on the recruitment method, but
overall inclusion criteria required participants to be AMAB, between 16 and 29
years of age, report having had sex with a man in the prior year or identify as
a SGM, live in the Chicago metropolitan area, and be an English speaker. Study
recruitment opened in February 2015. Participants
are followed through the developmental period of late adolescence to early
adulthood, which is a critical period of initiation and acceleration of sexual
behavior and substance use. Study visits occur every six months.

美国国家药物滥用研究所（National Institute on Drug Abuse, NIDA）于2014年资助RADAR项目，旨在从多维度、纵向收集族群与种族多元的年轻性与性别少数群体（sexual and gender minorities, SGM；例如男男性行为者（men who have sex with men, MSM）、跨性别女性、性别非遵从个体）的相关数据与生物样本，该群体出生时被指派为男性（assigned male at birth, AMAB），当前核心队列规模为1113人。
本研究的核心目标是从多层面视角，剖析该群体中与人类免疫缺陷病毒（human immunodeficiency virus, HIV）相关的健康共病综合征。该多层面研究设计聚焦于可能与HIV相关的个体层面、二元关系层面（即性与亲密伴侣关系）、社交网络层面（即社会、药物使用与性接触关联）以及生物学层面的影响因素。
该队列涵盖HIV阴性与HIV阳性人群，可构建包含感染前及感染后随访样本的生物标本与HIV序列数据资源库，为后续评估物质使用、HIV感染风险及发病机制的研究提供支撑。
本研究采用多队列加速纵向研究设计，最初纳入两个现有SGM队列，后续通过便利抽样与雪球抽样方法扩大招募规模。不同招募方式对应的入组标准略有差异，但总体纳入要求为：出生时被指派为男性、年龄介于16至29岁、近一年内有过男性性行为或自我认定为性与性别少数群体、居住于芝加哥大都市区且为英语使用者。研究招募工作于2015年2月启动。
研究对象将被随访至青春期晚期至成年早期这一关键阶段——该时期是性行为与物质使用行为启动及加速发展的关键窗口期。研究每6个月开展一次随访访视。