CROI 2017: Will There Be a New Wave of HIV Among People Who Inject Drugs in the U.S.?

While there is little evidence yet for a crossover of HIV from gay men who inject drugs to heterosexuals, several studies presented at last month's Conference on Retroviruses and Opportunistic Infections in Seattle found that the conditions do exist for it to happen. And they find a new generation of heterosexual people who inject drugs (PWID) who are not connected to conventional drug services, are sharing needles, and are increasingly interested in methamphetamine.

[Produced in collaboration with aidsmap.com]

Meanwhile, studies among men who have sex with men (MSM) found that while injecting methamphetamine is in decline among the white MSM population, it is increasing among black MSM.

Ever since there was an outbreak of HIV among white, largely rural heroin users in Indiana in 2015, there have been concerns that the conditions exist in some parts of the U.S. for more outbreaks among heterosexual people who inject drugs.

Increasing Methamphetamine Injection Among Heterosexuals

Evidence from Seattle’s local authority, King County in Washington State, sends warning signs that conditions do exist for a crossover of HIV from MSM to heterosexuals due to a rise in heterosexuals injecting methamphetamine -- and evidence that a significant proportion are sharing needles with MSM.

Sara Glick from the University of Washington in Seattle said that at present HIV prevalence among MSM who inject drugs is very high at 35%-40%, but is only 3% among heterosexual drug injectors.

Two different behavioral surveillance programs of PWID -- the Seattle Area section of the National HIV Behavioral Surveillance (NHBS) of Injecting Drug Users, and the King County Syringe Exchange Program survey -- looked at the proportion of people injecting drugs in the last year who had injected methamphetamine. The survey included only those who had been sexually active in the past year.

Among MSM, methamphetamine was not unexpectedly the prominent drug of choice. In the NHBS survey the proportion of injecting MSM who used methamphetamine rose from 55% in 2005 to over 80% in 2009 and stayed at that level thereafter. In the King County survey, methamphetamine was used by over 80% of MSM who inject drugs from 2013 onwards.

In contrast, the use of methamphetamine by heterosexual PWID, who had previously mainly used opiates, has been sharply increasing. Among heterosexual PWID the proportion using methamphetamine rose from 24% in 2009 to 69% in 2015, and in the King County survey from 16% to 57%. Among women who inject drugs, meth usage rose similarly, from 26% to 65% in the NHBS survey and from 25% to 61% in the King County one.

The pattern of meth usage is somewhat different among heterosexuals. MSM are more likely to inject methamphetamine by itself, but heterosexuals were more likely to inject it alongside heroin in a so-called "goofball." By 2015, 47% of heterosexual males who inject drugs reported goofball injection while only 10% reported using methamphetamine alone. The proportions were similar for women (43% vs 17%).

However, goofball injection also became more popular among gay and bi men, reported by only 18% of MSM who inject drugs (24% of meth users) in 2009 but by 34% of MSM who inject drugs (41% of meth users) by 2015.

Of most concern is that sharing is occurring between gay and bi men and heterosexuals. Among MSM who admitted sharing injection equipment, their last sharing partner had been a woman in 31% of cases and a heterosexual man in 14%. Among women who inject drugs, their last sharing partner had been a man who has sex with a man in 15% of cases and a heterosexual men in 7% of cases.

Prescription Painkillers as a Gateway to Injecting

Dita Broz from the Centers for Disease Control and Prevention (CDC) provided some troubling evidence that since 2000 a massive increase in the number of people with addiction to orally administered opioid painkillers has led directly to a new generation of injectors.

Deaths from overdoses of opioid drugs have increased in the adult population from 3 per 100,000 in 2001 to 10.4 per 100,000 in 2015 (1 for every 9600 U.S. adults per year), and the steepest increase has been among users of non-conventional medical opioids such as fentanyl, with a 10-fold increase. Medically prescribed opioids, including methadone, are responsible for 4.7 overdose deaths per 100,000 per year.

In order to find out whether non-injected opioid painkiller use was a precursor to injecting opioids, the NHBS conducted a respondent-driven survey of people who had injected opioids during the last year in 16 cities and asked them: "Were you hooked on painkillers before you injected for the first time?"

As this is a respondent-driven sample, there’s no denominator; we can’t tell if respondents were typical of PWID in their area. But there was a large increase in prior prescription opioid use in the last 25 years. Among people who first injected opioids before 1995, 12% said they had been hooked on painkillers before they started to inject. Among people who had started injecting any year after 2005, that proportion had increased to 50%. The median time between becoming addicted to prescription painkillers and injecting was 4 years.

Nearly 1 in 3 PWID (30.5%) said they had obtained the painkillers directly from prescriptions by doctors. Another 40% had got them from a friend or family; half of these had been bought, half given. 1 in 16 people (6.7%) had stolen them.

Prior prescription painkiller dependence was 2.9 times more likely among people who had first started to inject after 2000 than among people who had started before that. Also associated with prior painkiller addiction were younger age (under-30s were 70% more likely to have had prior painkiller dependence), being white rather than of other race/ethnicity (also 70% more likely), and, to some extent, being homeless (20% more likely) and female (10% more likely).

People who had started injecting after 2000 were less likely to have HIV (2% vs 6%), however.

Changing Patterns of Meth Use Among Gay Men

Two surveys looked at trends in methamphetamine use, both injected and non-injected, among MSM in the U.S. Both found that trends in drug use among gay men in general had stayed flat, but that who was using them had changed: use by black and poorer men had increased at almost exactly the same rate as it had decreased among white men.

Brooke Hoots of the CDC said that non-medical prescription opioid use had been reported by about 7.7% of MSM in 2008, 2011, and 2014, and almost the same proportion reported using methamphetamine (8% in 2014). A higher proportion of MSM reported using cocaine, but again with little variation (18.6% in 2008 and 19% in 2014).

More white than black MSM reported prescription opioid use, but while use among white men has been slightly, though not significantly, decreasing (from 10.2% in 2008 to 9.5% in 2014), it has risen significantly, from 4.2% to 5.9%, among black MSM.

There was a similar change related to income: prescription opioid use among MSM earning under $20,000 a year rose from 6.7% to 9.3%, while it fell among MSM earning over $75,000 a year, from 8.5% to 6.4%.

Similar trends were reported specifically from Washington DC, where Irene Kuo of George Washington University found complementary trends in meth use in white and black MSM. Among white MSM, the proportion in the city who reported using meth in the last year had gone down from 9.5% to 4.7% between 2008 and 2014. Among black MSM, however, it had gone up from 4.4% to 9.9%.

There were encouraging signs among white MSM that young men were not taking to meth: men over 30 were 2.5 times more likely to use meth than those under 30. On the other hand, as the national survey found, it is increasingly becoming a drug of the poor rather than the rich: white MSM earning under $20,000 a year were no less than 8.45 times more likely to use meth than men earning over $50,000 a year.

HIV-positive MSM were 10.6 times more likely to use meth if they were white and 4.2 times more likely if they were black but here, as ever, the question is whether their meth use increased their risk of HIV or their having HIV made them more likely to use meth. Interestingly, there was no significant association between condom use and meth use.

Finally, an interesting study from San Diego looked at what might be called the tertiary effects of opiate substitution therapy (OST), or medication-assisted therapy as it is often known in the U.S. People receiving OST not only suffer from fewer injection-related ills (primary benefit) and share needles less and pass on fewer infections to others (secondary effect), but they also initiate fewer people into injecting (tertiary benefit).

A group of PWID were asked: "Have you ever helped someone inject who had never injected before?" People in OST programs were 38% less likely to report that they had.

3/8/17

Sources

SN Glick, R Burt, K Kummer, et al. Increasing methamphetamine use among non-MSM who inject drugs in King County, WA. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 873.

D Broz, M Zlotorzynska, M Spiller, et al. "Hooked on painkillers" prior to first injection among PWID in 16 US cities. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 869.

B Hoots, D Broz, L Nerlander, et al. Changes in prescription opioid, meth, and cocaine use among MSM in 20 US cities. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 871.

I Kuo, R Patrick, J Opoku, et al. Changing patterns of crystal meth use in black & white MSM, Washington DC, 2008-2014. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 872.

ML Mittal, D Vashishtha, X Sun,et al. Opioid substitution therapy and initiation into injection drug use in San Diego, CA. Conference on Retroviruses and Opportunistic Infections. Seattle, February 13-16, 2017. Abstract 870.