People assigned male at birth who belong to a sexual or gender minority group were twice as likely to use methamphetamine following an HIV diagnosis, according to a study published in the Proceedings of the National Academy of Sciences.
Methamphetamine use has been a concern for gay and bisexual men for decades, said Brian Mustanski, PhD, the study’s lead author and director of the Institute for Sexual and Gender Minority Health and Wellbeing (ISGMH) and the Third Coast Center for AIDS Research.
“What we’re really trying to understand is the epidemiology of HIV, substance use and co-occurring mental health issues and also the risk and protective factors that help us understand why some young men develop these interconnected health issues more than others,” said Mustanski, who is also a professor of Medical Social Sciences.
Because previous research has shown a link between lowered dopamine signaling in HIV and the potential for substance use, Mustanski and his collaborators set out to investigate the connection further.
“People living with HIV have elevated systemic inflammation compared to people without HIV. One of the things that we’ve seen in experimental studies is that heightened inflammation suppresses dopamine signaling, and dopamine is really important for regulating motivation and mood,” said Joshua Schrock, PhD, research assistant professor at ISGMH and a co-author of the study. “Because of this elevated systemic inflammation, people living with HIV might be at higher risk of initiating meth use because of the dopamine boost that it provides.”
In the current study, investigators analyzed instances of first-time methamphetamine use among gay and bisexual men and transgender women who are part of the RADAR project, the largest longitudinal study of this community.
Participants in the study with a prior HIV diagnosis were twice as likely to report first-time methamphetamine use or have a positive urine toxicology result than study participants without HIV, according to the findings. Cocaine and cannabis use were also associated with greater odds of starting methamphetamine use.
“The findings of this study might inform screening practices in terms of identifying people who are at the highest risk of initiating meth use,” Schrock said. “It also points us towards biological underpinnings of stimulant use that might be important avenues for further study to help us learn how to better prevent and treat misuse of stimulants.”
Study participants who had heightened levels of C-reactive protein, a measure of systemic inflammation, were also more likely to start using meth, regardless of HIV status, according to the study.
“I think the findings speak to how important it is to have studies like RADAR, where we’re following people over time and we can look at characteristics that might have existed before HIV infection or before meth initiation, and that truly predict these outcomes,” said Mustanski, who is also founder and principal investigator of the RADAR study.
Moving forward, Mustanski and Schrock will continue to study the RADAR cohort and hope to better understand the relationships between HIV, inflammation and patterns of brain activity.
“We also hope to understand how substance use, HIV and also the stress that comes with being a young gay man in the United States – discrimination, homophobia, transphobia – and how those factors interact to potentially accelerate the aging process,” Mustanski said.
The study was supported by National Institute on Drug Abuse grant U01-DA036939, with additional support from the Third Coast Center for AIDS Research. This paper was a collaboration with Adam Carrico, PhD, at Florida International University.
About the RADAR project
Launched in 2014, the RADAR study is designed to provide insights into risk and protective factors for HIV and drug use among young men who have sex with men and transgender women.
Specifically, RADAR seeks to understand the connections between HIV, substance use, and social factors over time, with the ultimate goal of identifying barriers to implementing strategies to end the HIV epidemic.
More than 1,200 study participants from the Chicagoland area have been recruited and more than 100 scientific publications have been published since the study began.
Data from the RADAR study is made available to the scientific community on the project’s website.
