Although there is a decrease in the incidence of HIV, incidence rates remain high among men who practice slamming, sex without a condom with multiple sexual partners and group sex
A study that has looked at new HIV diagnoses among gay, bisexual and other men who have sex with men (GBHSH) in London and Brighton in recent years has identified key risk factors that predict subsequent infection. By far the most important factor is injecting drugs, especially in the context of chemsex. Although only 3% of the participants in this study reported injecting drug use, 16% of those who did so later had a positive HIV test result. The results have been published in the journal PLoS Medicine.
Men who reported using certain drugs - generally used in the context of chemsex - condomless sex with multiple partners or with partners with HIV, group sex, and sexually transmitted infections were at increased risk of contracting HIV. Men with a lower level of education were also more likely to test positive.
In this prospective observational cohort study, participants had to fill out behavioral questionnaires during the 2013-2016 period and gave their consent for researchers to verify their medical history until 2019 to see if they had been subsequently diagnosed with HIV.
This type of design avoids a common problem in cohort studies, which is that participants drop out of research as time passes. While records of new HIV diagnoses in England are anonymous, researchers were allowed to match data from study participants with data from new HIV diagnoses based on an anonymized code based on the person's last name. , date of birth, ethnic origin, country of birth, etc.
Researchers invited GBHSH men undergoing routine STI and HIV screenings at the London 56 Dean Street and Mortimer Market Center clinics and the Claude Nicol clinic in Brighton to participate. The 1,162 participants were primarily white (82%), college-educated (74%), and active (83%).
During the study period, HIV infections among GBHSH men in England were reduced by two-thirds. This epidemiological trend was reflected in the study where only 33 new HIV diagnoses were recorded in the cohort, which is fewer infections than the researchers had anticipated. Although this finding reduced the statistical power of the study, the researchers were still able to identify risk factors for HIV infection, based on the participants' responses to the questionnaire they had to fill out when they joined the cohort.
Two of the most important risk factors were related to drug use: 13 of the 321 men who used mephedrone, GHB / GBL or methamphetamine (substances that are used frequently in the context of chemsex) acquired HIV. This corresponds to a hazard ratio of 6.45 (95% confidence interval [95% CI: 1.84-22.64], which means that this factor increased the risk of a positive HIV test by six times in the future.
The results were even more striking for injection drugs: six of the 38 men who reported injecting drug use acquired HIV (hazard ratio (RR): 27.96; 95% CI: 6.99 - 111.85 ). While the questionnaire did not ask what specific drugs they injected, all 38 slamming participants reported using drugs commonly used in the context of chemsex. The findings show that nearly half of the 13 men who acquired HIV and reported using chemsex-associated drugs also reported slamming.
More than half of the study participants reported having had recent anal intercourse without a condom, including 26 of those who subsequently contracted condom (RR: 3.75, 95% CI: 1.31-10.74). There was a tiered relationship between the number of sexual partners and the risk of acquiring HIV. For example, 5 of the 60 men who had sex without a condom with between five and ten sexual partners in the last three months acquired HIV (RR: 9.60; 95% CI: 2.58 - 35.76).
In addition to the aforementioned risk factors, other HIV risk factors were identified, including: recent condomless sex with a sexual partner whose HIV status is known (14 of the 147 participants who reported acquired HIV status). HIV; RR: 6.45; 95% CI: 3.15-13.22); adopt the versatile role for anal sex (21 of the 362 men who reported it contracted HIV [RR: 6.35; 95% CI: 2.18 - 18.51]); group sex (64 of the 500 who reported it contracted HIV [RR: 8.81; 95% CI: 3.07 - 25.24]); having sex in exchange for money or drugs (4 of the 55 men who reported them acquired HIV [RR: 3.27; 95% CI: 1.14 - 9.38]); having used post-exposure prophylaxis against HIV (11 of the 240 men who reported it acquired HIV [RR: 2.29; 95% CI: 1.09 - 4.81]); having a bacterial STI (21 of the 440 men who reported it acquired HIV [RR: 3.95; 95% CI: 1.81 - 8.63]). The only sociodemographic factor that was significantly associated with acquiring HIV was having a lower educational level.
HIV infection was not associated with age, housing status, financial status, marital status, recent HIV tests, fisting, sex toys, HIV pre-exposure prophylaxis (PrEP), smoking, alcohol, depressive symptoms, or anxiety symptoms.
In a context of increasing access to early HIV treatment and PrEP, the results of this study highlight the contexts and risk behaviors associated with HIV. The elevated risk associated with drug use could reflect the sexual behavior it triggers, although blood transmission from needle sharing in the context of chemsex cannot be ruled out.
Source: Aidsmap / Elaboración propia (gTt-VIH)
References: Hanum N et al. Trends in HIV incidence between 2013–2019 and association of baseline factors with subsequent incident HIV among gay, bisexual, and other men who have sex with men attending sexual health clinics in England: A prospective cohort study. PLoS Med 18(6): e1003677, 2021
