On Monday, March 5, the attendees of the annual Conference on Retroviruses and Opportunistic Infections (CROI) gathered in Boston's Hynes Convention Center in search of answers to the most pressing public health crisis facing the U.S.: the opioid epidemic. Because of the surge in injection drug use over the past decade, HIV outbreaks like the one seen in Indiana in 2015 are now a real concern in communities previously untouched by the AIDS crisis.
The five panelists painted a bleak picture of the scale of the country's addiction crisis, noting that the never-before-seen dynamics of the current drug epidemic require creative approaches to HIV treatment and prevention among people who inject drugs.
The symposium, "HIV in People Who Inject Drugs: An Evolving and Persistent Challenge," included presentations that characterized the current interplay of HIV and injection drug use, highlighted the challenges in applying traditional interventions, and emphasized that our new reality requires new solutions.
The association between injection drug use and HIV has existed since the dawn of the AIDS crisis, yet people who inject drugs tend to be overlooked as a key population, noted session moderator Adeeba Kamarulzaman, M.D., University of Malaya Medical Centre, Kuala Lumpur, Malaysia.
"Globally, there are approximately 12 million people who inject drugs. Of those, it's estimated that about 1.6 million people are living with HIV, which makes up to approximately 10% of the global HIV prevalence," Kamarulzaman said.
"Of the key populations, I think people who inject drugs have been the ones who essentially the HIV epidemic is least controlled," added Kamarulzaman. Gazing out at the attendees, she noted, "Looking the number of people who have come to this session, I'm sure there is a lot of interest."
Related: Why Did the Opioid Epidemic Develop and How Do We Stop It?
New Epidemic, New Problems
To understand the current epidemic of HIV among people who inject drugs, it's helpful to glance back at the prior generation. Lucia V. Torian, Ph.D., New York City Department of Health and Mental Hygiene, did just that, presenting an analysis of molecular surveillance data from New York City that "confirmed the epi-data suggesting that the city had two distinct waves of HIV among injectors."
The first wave began in the mid-1970s, and its surviving members are largely black and Latinx and use drugs such as heroin and cocaine, she noted.
The second wave began in the late 1990s, and has a far younger demographic at time of diagnosis, is more broadly distributed by race and geography, and includes a wider range of drugs, including injectable party drugs such as methamphetamine.
The differences in the current generation of HIV-positive people who inject drugs go even further than that, according to Sheryl Lyss, M.D., Centers for Disease Control and Prevention (CDC), Atlanta.
"There are now more HIV diagnosis occurring among [people who inject drugs] who are white than who are black, more among those aged 13-34 than 35-40 or greater than or equal to 50 years, and more among those who reside outside, rather than within, large central metropolitan areas," Lyss said.
Lyss continued, "These changes in pattern require changes in our response, including outbreak planning, careful monitoring at national and subnational areas, and rapid multi-modal interventions."
Promisingly, the number of HIV diagnosis per year among people who inject drugs declined 35% nationally from 2010 to 2016, but the decline was not uniform among subgroups, Lyss said. Meanwhile, "given the number of diagnoses in 2014 and 2016 is about equal, [this] raises the question of whether the longstanding decline in diagnoses of people who inject drugs may have stalled," she said.
In an effort to understand the current HIV risk factors among people who inject drugs, the CDC analyzed data from a survey of injection drug users conducted by the National HIV Behavioral Surveillance across 22 cities.
The results of that analysis were presented by Christine Agnew-Brune, Ph.D., M.P.H., also with the CDC. The first analysis compared people who inject drugs who had recently acquired HIV to those who were HIV negative, finding that recent infection was more likely among those reporting male/male sex or a greater number of sex partners in the past year, as well as reporting injection of heroin in combination with other drugs, or drugs other than heroin.
The second analysis compared HIV-positive people who inject drugs with recent infections with those with non-recent infections. "There were many significant associations in the second analysis," such condomless sex and lack of health insurance, noted Agnew-Brune. "But I want to point out the findings that [people who inject drugs] who were white and [people who inject drugs] who had graduated high school were more likely to be recently HIV infected, which was not necessarily anticipated."
Considering the strong association of sex behaviors with HIV risk, Agnew-Brune suggested that "promoting not only safer injection practices but also safer sex practices will be important in preventing new HIV infections among [people who inject drugs]."
While panelists emphasized the need for new, targeted interventions, one presentation highlighted just how challenging it might be to tailor those interventions considering the current dynamics of drug addiction.
Daniel Feaster, Ph.D., University of Miami, reported the three-year outcomes of a previously reported study called Project HOPE, the aim of which was to test three interventions deployed over six months for HIV-positive people who inject drugs. In the first arm, patients were given 11 sessions with a patient navigator; in the second arm, patients were compensated monetarily for harm reduction behaviors; the third arm was given treatment as usual.
Three years after the interventions, there was no difference in viral suppression among the groups, Feaster told the audience.
"Despite intensive, time-limited intervention, the long-term success in viral suppression is about 33%," he said. Twenty-five percent of the study participants died within three years, and the rates of substance use remained high, at over 65% across the cohort. Among those who survived, viral suppression was 50%.
Importantly, Fester was able to tease out regional differences, noting that, overall, sites located in northern states had better outcomes than those in the South. Meanwhile, drug users in the South were more likely to use stimulants, while those in the North were more likely to use opioids.
"Stimulant use is the thing, for our study, that consistently predicted more problems in terms of the care cascade," he said. "Our real take home from this is, given the low viral suppression rate and continued high substance use, we really need to have ongoing interventions with this population" beyond six months, Feaster continued.
The tragic number of deaths attributable to the overlapping epidemics of substance use and HIV reinforces the need for continued research, the panelists noted. In fact, by studying the health and medical status of the recently deceased, researchers are hoping to build better targeted interventions for those who remain at risk of overdose, according to Sarah Lomax Braunstein, Ph.D., New York City Department of Health and Mental Hygiene.
"New York City overdose deaths increased 143% between 2010 and 2016," said Torian. However, Braunstein noted that "drug [overdose] deaths among [people with HIV] have not yet been described."
In her research, Braunstein sought to construct a "high-mortality continuum of care." In other words, she evaluated NYC surveillance data of overdose deaths among people with HIV from 2007 to 2015 to better understand the pre-death health profile of those who had died.
The vast majority (93%) of overdose deaths were accidental. Nearly 80% of people with HIV who died of a drug overdose -- whether intentional or unintentional -- had been retained in HIV care at some point in the year prior to their deaths.
As Braunstein noted, her research highlights missed opportunities to save lives.
Meanwhile, people living with HIV and also suffering from addiction are facing a very real risk of overdose or death while researchers race to understand the complex interplay of these two epidemics.