Association of Sexualized Drug Use Patterns with HIV/STI Transmission Risk in an Internet Sample of Men Who Have Sex with Men from Seven European Countries.

We estimated the prevalence of overall sexualized drug use (SDU) and of chemsex in particular, assessed patterns of drug use, and identified subpopulations of men who have sex with men (MSM) where SDU and chemsex are more frequent. Using data from an online survey of 9407 MSM recruited during 2016 in 7 European countries, we calculated the proportion of participants who reported SDU and chemsex (mephedrone, methamphetamine, and/or GHB/GBL) in the last 12 months. We grouped the different drug-use combinations in patterns and described sexual risk behaviors, sexually transmitted infections (STI), and HIV seropositivity for each one of them. Factors associated with SDU and chemsex were assessed with two logistic regression models. SDU was reported by 17.7% and chemsex by 5.2%. Risk indicators increased through the different SDU patterns but were higher within those including chemsex drugs. In the multivariate analysis, chemsex was independently associated with living in Slovenia. Both SDU and chemsex were independently associated with living in Spain; being < 50 years old; living in cities of > 500,000 inhabitants; being open about their sex life; reporting transactional sex; condomless anal intercourse; having received an STI diagnosis and with being HIV positive or having been tested ≤ 12 months ago. Magnitude of associations was higher in the chemsex model. One in five participants reported SDU, but prevalence of chemsex was notably lower. However, the risk profiles and higher prevalence of HIV/STIs among those involved in chemsex suggest the existence of a subpopulation of MSM that could be playing a relevant role in the HIV and STI epidemics, especially in very large cities of some countries.

Sexual Behavior and Sexually Transmitted Infections Among Swingers: Results From an Online Survey in Belgium.

Swingers are couples practicing consensual extradyadic heterosexual relations. This subculture is defined by venues and online communities. This study aimed to assess swingers' lifestyle, sexual health, and history of testing for sexually transmitted infections (STIs) and to review risk factors for sexual risk behavior and STI transmission. An online survey was distributed through venues, chat websites, and dating websites. Most of 480 swingers starting the survey completed it (n = 392, 81.6%). Women (n = 146) reported more frequent swinging (p = 0.013), same-sex contacts (p < 0.001), and more sex under influence of alcohol (p < 0.001). Men (n = 334) reported more anal sex (p = 0.002) and condomless vaginal sex (p = 0.004). Of respondents tested, 25.7% ever received an STI diagnosis. Using logistical regression, being male, older, single, and party drug use were associated with sexual risk behavior (p = 0.009). Higher frequency of swinging was associated with an STI diagnosis (p = 0.036). Swingers were sexually active, reported factors associated with sexual risk behavior, and were more diagnosed with an STI compared to the general population. Many swingers were tested for STIs. Nonetheless, implementation of tailored testing strategies should be considered given their elevated risk for STI acquisition.

Sexually Transmitted Infections and Associated Risk Factors Among Male Clients of Sex Workers: A Cross-Sectional Pilot Project in Antwerp, Belgium.

Introduction: Prevalence of sexually transmitted infections (STIs) is increasing in Belgium in recent years. Clients of sex workers form a key population for acquisition of STIs, due to their sexual relations, with or without a condom, with sex workers. STI testing uptake is low among clients of sex workers, and prevalence of STIs remains to be investigated in Belgium. Therefore, we offered STI-testing to clients of sex workers during outreach sessions in Antwerp. Methods: Time location sampling (TLS) was used to improve representativeness of the sample during ten test sessions in the red light district, Antwerp in May and September 2019 by using a passive approach. Individuals that were interested to get tested for STIs could enter the study. Participants completed an online survey and samples for STI testing were collected. Testing included HIV, syphilis, Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (Ng). Test results were communicated via a cell phone message (for negative test results) or by phone (for positive test results). Results: In total, 154 male clients of sex workers with a median age of 38 participated. A total of eight Ct and one Ng infections were detected. TLS analysis revealed a Ct/Ng prevalence of 8.2%. No new HIV nor syphilis infections were detected. Using univariate analysis, testing positive for STI was associated with younger age and anorectal sex with a sex worker. Using multivariate analysis, an STI-positive test result was associated with being younger, having non-Belgian nationality, and being in a relationship. Conclusion: Our study found a substantial prevalence of Ct/Ng which highlights the need for sensitization and facilitation of STI testing among clients of sex workers. It is difficult to compare results due to the lack of reference material. Moreover, our relatively small convenience sample limits generalizability of results. However, phone counseling (for positive test results) was accepted, linkage to care was provided, and partner notification was facilitated.