TYPE Original Research PUBLISHED 15 November 2022 DOI 10.3389/fpubh.2022.997730 Sexualized drug use among men OPEN ACCESS who have sex with men in Madrid and Barcelona: The EDITED BY Roman Shrestha, University of Connecticut, United States REVIEWED BY gateway to new drug use? Zixin Wang, The Chinese University of Hong Kong, China Juan-Miguel Guerras1,2 , Juan Hoyos3*, Marta Donat1,2 , Blanca Iciar Indave Ruiz, European Monitoring Centre for Drugs Luis de la Fuente2,4 , David Palma Díaz2,5 , Oskar Ayerdi6 , and Drug Addiction, Portugal Jorge N. García-Pérez7 , Patricia García de Olalla2,5,8† and *CORRESPONDENCE Juan Hoyos María-José Belza1,2† on behalf of the Methysos Project Group hoyosmiller@hotmail.com 1 Escuela Nacional de Sanidad, Instituto de Salud Carlos III, Madrid, Spain, 2 CIBER Epidemiologia y † Salud Pública (CIBERESP), Madrid, Spain, 3 Independent Researcher, Madrid, Spain, 4 Centro Nacional These authors have contributed de Epidemiología, Instituto de Salud Carlos III, Madrid, Spain, 5 Servicio de Epidemiología, Agència de equally to this work and share senior Salut Pública de Barcelona, Barcelona, Spain, 6 Centro Sanitario Sandoval, Instituto de Investigación authorship Sanitaria San Carlos, Hospital Clínico San Carlos, Madrid, Spain, 7 Unidad de ITS de Vall SPECIALTY SECTION d’Hebron-Drassanes, Hospital Vall d’Hebron, Barcelona, Spain, 8 Institut d’Investigació Biomèdica This article was submitted to Sant Pau, Hospital Universitari Sant Pau, Barcelona, Spain Public Health Education and Promotion, a section of the journal This original study compares the prevalences of drug use for any purpose Frontiers in Public Health and for sexualized drug use (SDU) among MSM. It also describes relevant RECEIVED 19 August 2022 ACCEPTED 25 October 2022 characteristics of first SDU, analyzes to what extent SDU has been the PUBLISHED 15 November 2022 first experience (the gateway) with different drugs by age and explores CITATION the correlates of SDU. Study participants included 2,919 HIV-negative MSM Guerras J-M, Hoyos J, Donat M, de la attending four HIV/STI diagnosis services in Madrid and Barcelona. They Fuente L, Palma Díaz D, Ayerdi O, García-Pérez JN, García de Olalla P answered an online, self-administered questionnaire. Poisson regression and Belza M-J (2022) Sexualized drug models with robust variance were used. About 81.4% had ever used any use among men who have sex with men in Madrid and Barcelona: The drug, and 71.9% had done so in the last-12-months, while 56% had ever gateway to new drug use? engaged in SDU, and 50% had done so in the last-12-months. Participants Front. Public Health 10:997730. under 25 years old had the lowest prevalences of SDU, and the 25–39 age doi: 10.3389/fpubh.2022.997730 group the highest, except for Viagra, which was higher among those over COPYRIGHT © 2022 Guerras, Hoyos, Donat, de la age 40. The most frequently used drugs for first SDU were poppers (53.6%), Fuente, Palma Díaz, Ayerdi, cannabis (19.6%) and Viagra (12.2%). These drugs were also the most ever García-Pérez, García de Olalla and consumed for SDU. Among sexualized users, methamphetamine (78.3%) and Belza. This is an open-access article distributed under the terms of the Mephedrone (75.4%) were used always/most of the times for sex in the Creative Commons Attribution License last-12-months. Around 72.2% of Mephedrone sexualized users and 69.6% (CC BY). The use, distribution or reproduction in other forums is of Methamphetamine vs 23.1% of ecstasy users’ first consumption of these permitted, provided the original drugs involved use for sex. These drugs were provided to them free where author(s) and the copyright owner(s) they have sex for 66.8, 79.1, and 31.9%, respectively. On that occasion, 8.1% are credited and that the original publication in this journal is cited, in of Mephedrone, 6.8% of Methamphetamine and 18.4% of ecstasy users had accordance with accepted academic sex only with steady partner; with 50.2, 56.2, and 26.2% respectively using practice. No use, distribution or a condom with any partner. SDU in the first use was associated with similar reproduction is permitted which does not comply with these terms. variables for recreational and chemsex drugs. The highest prevalence ratios were for having ever been penetrated by >20 men and having ever injected drugs. It can be concluded that the prevalence of SDU was more than half of the prevalence for any purpose. Thus SDU was the gateway to use for many drugs in an important proportion of users, who frequently consumed drugs Frontiers in Public Health 01 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 that were free and had condomless anal sex with occasional and multiple partners. These circumstances were much more common for chemsex than for recreational drugs. KEYWORDS men who have sex with men, sexualized drug use, chemsex, drug use, drug initiation Introduction used, when in reality, studies should use the term SDU, as they include substances other than chemsex drugs (18– In the last decade, much research has been published on 21). Many studies have focused on assessing whether or not Sexualized Drug Use (SDU) by men who have sex with men users of particular drugs have a higher prevalence of risky (MSM) (1–4) which involves drug use just before or during sexual behaviors or a higher incidence of HIV, but it is sex. Most of these studies have focused on what in the UK is not always possible to discriminate SDU from recreational known as “chemsex,” which involves sexual encounters between drug use. Although, in many cases, SDU is probably the MSM (usually group-sex) under the effects of certain drugs. appropriate term (22–24), especially for certain substances, Chemsex has recently become widespread among MSM. The in other cases we lack information in this regard (25–31). most commonly labeled “chemsex drugs,” or “4-chem” drugs One of the most studied substances, especially in the USA, include (5): methamphetamine, mephedrone, GHB/GBL, and is methamphetamine (23, 24, 29, 31–33), which, together ketamine. “3-chem” refers to methamphetamine, mephedrone, with mephedrone, is one of the drugs most associated GHB/GBL (1, 6, 7), and “2-chem” refers to the two most with chemsex. closely related drugs: methamphetamine and mephedrone. Studies of a wide range of drugs show that the prevalence of The growth of this phenomenon has been closely linked to SDU of the most commonly used drugs for any purpose (such as the proliferation of geosocial networking dating apps which cannabis or cocaine) tend to be much higher than the prevalence facilitate both contact with potential sexual partners and the of chemsex drugs (10, 34). Besides making the sexual experience acquisition of substances (8). Geosocial networking dating more intense, pleasurable or long-lasting, there are many other apps facilitate and multiply the possibilities of finding sexual reasons for drug use (recreational, performance enhancement, partners with whom to engage in these practices, and can etc.), Analysis of the available information suggests that, with play a relevant role in the practice of chemsex (9). The the exception of poppers and the 4-chems, psychoactive drugs public health significance of SDU is primarily related to the are probably used more frequently by most MSM for purposes fact that chemsex drugs have been associated with high risk other than sex. However, there are no studies comparing the sexual behaviors and an increased likelihood of acquiring prevalence of sexualized use of a broad range of drugs with the HIV, HCV and other STIs (4, 6). Individuals who use these prevalence of use for any purpose. Likewise, we can assume that substances are on the top of the “risk ladder,” according to SDU (whether one has taken the substance intentionally for sex the type of drugs used for SDU, especially among those who or not), could be the first experience (the gateway) with different practice chemsex (10), being a priority group to be included drugs for a significant percentage of users, and it is possible that in PrEP programs (11). Other health consequences, such as it serves as an exclusive gateway for chemsex drugs. However, substance dependence (12), mental health effects (13, 14) there are no studies that confirm or refute these hypothesis. and deaths from overdose- in particular by GHB (15, 16) Likewise, there is no additional drug-specific information on the or methamphetamine (12)- have been much less studied, but circumstances surrounding the first sexualized use, as almost should not be underestimated. all studies focus on the last SDU or the last sexual encounter Although the chemsex phenomenon was first described (34, 35). in the United Kingdom and has been investigated mainly in This study focuses on MSM and aims to estimate the Western countries, it is a behavior that has been observed prevalence of use of certain drugs for any purpose and internationally (1–4). Many studies only consider three or four specifically for sex, the percentage of participants for whom each chemsex drugs (5, 14, 17). The label “chemsex” is frequently substance was the first drug or the most commonly used drug for sex, and the proportion who used the drug always or most of Abbreviations: aPR, adjuted prevalence ratio; CI, confidence interval; cPR, the time for sex. We also estimate, the proportion of participants crude prevalence ratio; HCV, hepatitis C virus; MSM, men who have sex for whom SDU was the gateway to use by drug and age group. with men; SDU, sexualized drug use; STI, sexually transmitted infection; We also describe some relevant characteristics of the first SDU UK, United Kingdom. by drug. Frontiers in Public Health 02 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 Methods use for any purpose and for sexualized drug use. To simplify the reading of this article and offer the opportunity for an in depth Project design and sample recruitment look at the contents of the questionnaire, Supplementary Table 1 of the Annex presents all the variables addressed in this article The Methysos Project is a research project that aims to and their corresponding original categories. analyze the prevalence and characteristics of drug use for In the drug use module, we first inquired about the use any purpose, with a special focus on SDU, in MSM living in of drugs for any purpose: “When was the last time you used Spain. The project was funded by the National Plan on Drugs any of the following drugs?” Table 1 and Figure 1 show the and was approved by the Research Ethics Committee of the 13 substances or groups of substances that we asked about. Instituto de Salud Carlos III (CEI PI 44_2018_subproyecto1-v2 We included sex performance enhancing drugs like Viagra or and CEI PI 44_2018_subproyecto2). In this study, we present similar drugs, although these substances are not psychoactive. the results from the first survey of the project, carried out We next inquired about SDU: “Which drugs have you ever in four diagnostic facilities in the two largest Spanish cities: consumed during anal sex or in the previous 6 h?” Then, we the two most important sexually transmitted infection clinics inquired about the first two drugs the individual had used in Spain—Sandoval, in Madrid and Drassanes, in Barcelona— for sex, and which were the two drugs most used for sex in and in two community programs for rapid HIV-testing-the his lifetime. In order to keep the questionnaire brief and to Pink Peace Program, in Madrid, and the Public Health Agency, ensure a better questionnaire completion, several supplementary in Barcelona-. The STI clinics provide on-demand services questions were asked pertaining to certain drugs. No further (including Prep) and perform laboratory based testing for all questions were proposed for hallucinogens, tranquilizers, and STIs, whereas the community programs also carry out different opiates, due to the very low expected prevalence. For the rest kinds of active recruitment (including ads and profiles on dating of the drugs, two more questions were asked: “when was the apps for MSM), and only offer rapid testing for HIV, syphilis and last time you used this substance to have sex?” and, “in the last sometimes for HCV. 12 months, when you have used this substance, has it been: (1) The study included only MSM without a previous HIV always just before or during sex; (2) most of the time just before diagnosis, because this group accounted for the vast majority of or during sex, (3) half of the time just before or during sex; (4) attendees, and we preferred to obtain a homogenous group to few times for sex.” Except for poppers, Viagra and cannabis, we increase the external validity and comparability of the results. also proposed a set of questions related to the first time each Therefore, of all those MSM who accessed these four facilities, substance was used for sex: (1) whether the first time he used for only those whose last HIV test had been negative or those sex was the first time he used for any purpose, and if not, (2) how who had never had a HIV test were offered the opportunity many days had he used it before; (3) if it was used intentionally to participate (Supplementary Figure 1 of Annex). Those who for sex; (4) and with which types of partners he had sex on that accepted signed an informed consent. The recruitment of the occasion and with which partners he had used condoms. sample included in this study took place from September 2018 Detailed definitions of the drug use variables in the to December 2020. questionnaire, as well as a summary of the terms used to No sample size calculation was performed. We attempted group the drugs can be found in Supplementary Tables 2, 3 of to recruit a sufficiently large number of participants using non- the Annex. probabilistic convenience sampling to have adequate statistical power to accurately estimate outcomes and detect statistically significant differences between subgroups of interest. Statistical analysis The final sample of the study was 2,919 participants: 1,816 from Madrid (627 from the STI center and 1,189 from the Most of the variables were collected in a more disaggregated community center) and 1,103 from Barcelona (421 from the STI form than presented here, since some of the original categories center and 682 from the community center). were grouped together based on their frequencies and the rationale for the analysis. Supplementary Table 1 of the Annex shows how the original variables and categories from the Data collection instruments questionnaire were managed to obtain the final variables and categories used. The tables and figures in this article present Participants answered a self-administered online the considered substances in a different order than that which questionnaire, without personal identifiers, on a tablet, was used in the questionnaire, to facilitate understanding. Those while waiting to be seen. The questionnaire included sections with similar results have been grouped together. on sociodemographics, sexual behavior, sexual and injecting Comparisons of independent variables were assessed using risky behaviors, history of HIV and other STI testing, and drug Pearson’s χ 2 and Fisher’s exact tests. For the analysis of Frontiers in Public Health 03 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 1 Sample characteristics of MSM* from Madrid and Barcelona by lifetime sexualized drug use (N = 2,919). Ever sexualized drug use Never sexualized drug use Total P-value N = 1,636 N = 1,283 N = 2,919 N % N % N % Recruitment City of testing 0.927 Madrid 1,019 62.3 797 62.1 1,816 62.2 Barcelona 617 37.7 486 37.9 1,103 37.8 Kind of testing program <0.001 Comunity program 1,005 61.4 866 67.5 1,871 64.1 STI diagnostic center 631 38.6 417 32.5 1,048 35.9 Sociodemographics Age (years) <0.001 <25 218 13.3 234 18.2 452 15.5 25–39 985 60.2 694 54.1 1,679 57.5 ≥40 433 26.5 355 27.7 788 27.0 Country of birth 0.427 Spain 975 59.6 794 61.9 1,769 60.6 Latin America 475 29.0 356 27.7 831 28.5 Others 186 11.4 133 10.4 319 10.9 Size of city of residence (last 12 months) 0.365 ≤100.000 162 10.0 148 11.6 310 10.7 100.000–1 million 197 12.2 157 12.3 354 12.2 >1 million 1,262 77.9 971 76.1 2,233 77.1 Level of education 0.986 Up to upper secondary 109 6.7 85 6.7 194 6.7 Post-secondary 553 33.9 437 34.2 990 34.1 University 968 59.4 755 59.1 1,723 59.3 Employment status (last 12 months)** <0.001 Employed 772 76.8 578 72.8 1,350 75.0 Unemployed 85 8.5 47 5.9 132 7.3 Others 148 14.7 169 21.3 317 17.6 Economic situation (last 12 months) 0.267 Comfortable/It is OK 964 59.5 777 60.7 1,741 60.0 Tight 522 32.2 383 29.9 905 31.2 Dificult/very difficult 133 8.2 121 9.4 254 8.8 Co-habitation (last 12 months)** 0.028 Alone 383 38.0 343 43.1 726 40.3 With some people 624 62.0 452 56.9 1,076 59.7 Sexual behavior Gender of sex partners (ever) 0.015 Only men 990 60.5 833 64.9 1,823 62.5 Men & women 646 39.5 450 35.1 1,096 37.5 Age at first sexual intercourse with another men (years) <0.001 ≤15 314 19.2 183 14.3 497 17.0 16–20 934 57.1 663 51.8 1,597 54.7 21–24 237 14.5 224 17.5 461 15.8 ≥25 151 9.2 211 16.5 362 12.4 (Continued) Frontiers in Public Health 04 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 1 (Continued) Ever sexualized drug use Never sexualized drug use Total P-value N = 1,636 N = 1,283 N = 2,919 N % N % N % Lives sex life with men <0.001 Openly 1,075 66.5 679 53.0 1,754 60.6 Not openly 541 33.5 601 47.0 1,142 39.4 Place where the largest number of partner were found <0.001 Dicos/clubs/bars 258 16.2 137 11.2 395 14.0 Saunas 188 11.8 97 7.9 285 10.1 Private parties 91 5.7 13 1.1 104 3.7 Apps/webs 979 61.3 867 70.6 1,846 65.3 Cruising places 48 3.0 48 3.9 96 3.4 Others/no search 33 2.1 66 5.4 99 3.5 Place where the largest number of partner were found <0.001 Discos/bars-saunas-private parties 537 33.6 247 20.1 784 27.8 Others 1,060 66.4 981 79.9 2,041 72.3 Risk behavior Number of men who had penetrated you (ever) <0.001 None-one 79 4.8 223 17.4 302 10.4 2–20 686 41.9 698 54.4 1,384 47.4 >20 871 53.2 362 28.2 1,233 42.2 Number of men who had penetrated you (last 12 months) <0.001 None-one 461 28.2 651 50.9 1,112 38.1 1–5 462 28.2 359 28.1 821 28.2 >5 713 43.6 270 21.1 983 33.7 Ever been paid for sex <0.001 No 1,173 71.7 1,091 85.0 2,264 77.6 Yes 462 28.3 192 15.0 654 22.4 Ever paid for sex <0.001 No 1,304 79.7 1,095 85.3 2,399 82.2 Yes 332 20.3 188 14.7 520 17.8 Ever injected drugs <0.001 No 1,557 96.1 1,277 99.6 2,834 97.6 Yes 64 3.9 5 0.4 69 2.4 Ever injected steroids <0.001 No 1,493 91.9 1,242 96.8 2,735 94.1 Yes 131 8.1 41 3.2 172 5.9 History of HIV and other STI testing Time since last HIV test <0.001 <6 months 875 53.5 528 41.2 1,403 48.1 >6 months 703 43.0 633 49.4 1,336 45.8 Never tested before 57 3.5 120 9.4 177 6.1 HIV diagnosis in the recruitment consultation 0.953 No 1,585 98.1 1,247 98.1 2,832 98.1 Yes 31 1.9 24 1.9 55 1.9 Ever diagnosed with an STI <0.001 No 533 32.7 714 56.5 1,247 43.1 Yes 1,097 67.3 550 43.5 1,647 56.9 * MSM, men who have sex with men. ** These questions were not included in Barcelona. Frontiers in Public Health 05 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 FIGURE 1 Lifetime and last 12 months prevalence of drug use for any purpose and for sexualized drug use, among MSM* from Madrid and Barcelona (%). *MSM, men who have sex with men. correlates of sexualized use for the first use of recreational drugs Prevalence of drug use for any purpose and of chemsex drugs, Poisson regression models with robust and of sexualized drug use variance were used (36). Both crude and adjusted prevalence ratios (cPRs and aPRs) and 95% confidence intervals (95%CI) As shown in Figure 1, some 81.4% of participants had ever were calculated. Variables with a significance level of <0.25 used any drug, and 71.9% had done so in the last 12 months. in the bivariate analysis were introduced into the multivariate Except for opiates and hallucinogens, all substances had been model—after collapsing the number of categories for some used by more than 10% in the last 12 months. However, some variables. The Akaike Information Criteria was used to perform substances had very high prevalences of use: 61.9% of the model comparisons in order to select the final model. participants had ever used poppers and 56.7% cannabis; 50.9% These analyzes were performed using Stata v. 17 (Statacorp, and 39.9%, respectively, had done so in the last 12 months. In College Station, TX). terms of sexualized use, 56.0% had ever had sexualized drug use and 49.9% had done so in the last 12 months. Opiates, sedatives and hallucinogens had ever been used by 2% or less of Results participants; amphetamines, ketamine, methamphetamine and mephedrone had been used by between 6.5% and 8.5 %, cannabis General characteristics of the sample and Viagra by 21% and poppers by 44.5%. Prevalences for the last 12 months were similar, but a little lower (between 2 and 5 In terms of sociodemographic characteristics: 73.0% of the percentage points). participants were under 40 years of age, 39.4% were born abroad, 77.1% lived in the municipalities of Madrid or Barcelona, 59.3% had university-level studies, 60.0% had a comfortable economic situation and 40.3% had lived alone during the last 12 months. Characteristics of sexualized drug use of Concerning sexual and risk behavior: 62.5% had only ever had different substances by age sex with men, 17.0% had had their first sexual relationship with a man before age 16, 60.6% lived their sexual life with men Table 2 shows that the <25 age group had significantly lower openly, 65.3% had met most of their partners through websites prevalences of SDU for most of the drugs than older age groups. or dating apps; 5.5% had never been penetrated and 42.2.% had The 25–39 age group had the highest prevalences, except for been penetrated by more than 20 men in their lives; 22.4% had Viagra which was significantly higher among those over age 40. been paid for sex; 17.8% had paid for sex; 2.4% had ever injected Continuity of use was very high; more than 50% of those drugs and 5.9% had injected steroids. Regarding HIV and STI who had ever used Viagra and poppers for SDU had also used testing, 48.1% had been tested for HIV in the last 6 months them in the past month, and this proportion was 40% for and just 6.1% had never been tested before. About 1.9% were cannabis, GHB, methamphetamine and mephedrone. Viagra diagnosed with an HIV infection in that consultation, and 56.9% and poppers had greater continuity among the older age had at some point been diagnosed with an STI (Table 1). group, while the other drugs generally had greater continuity Frontiers in Public Health 06 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 2 Characteristics of sexualized drug use of different drugs by age, among MSMa from Madrid and Barcelona (%). All Age P-value <25 25–39 ≥40 Ever-sexualized drug useb Any drug 56.0 48.2 58.7 54.9 †, U Viagra 21.9 9.7 20.3 32.5 †, U, ‡ Poppers 44.5 37.8 47.8 41.2 †, ‡ Cannabis 21.3 22.3 23.2 16.8 U, ‡ Amphetamine 6.5 4.4 7.7 5.1 †, ‡ Cocaine 15.2 7.7 16.7 16.2 †, U Ecstasy 11.7 8.6 13.6 9.3 †, ‡ Ketamine 7.2 6.4 8.2 5.6 ‡ GHB/GBL 13.4 10.0 15.7 10.5 †, ‡ Methamphetamine 8.2 5.8 9.6 6.5 †, ‡ Mephedrone 8.3 5.8 9.4 7.2 † Continuity of sexualized use (last month)c Viagra 53.6 47.7 49.7 60.0 ‡ Poppers 53.3 44.4 54.3 55.4 †, U Cannabis 47.5 52.0 49.7 37.0 U, ‡ Amphetamine 30.5 45.0 28.1 30.8 Cocaine 32.6 44.1 34.9 24.2 U, ‡ Ecstasy 26.8 35.1 26.6 22.9 Ketamine 31.8 46.2 32.8 19.5 U GHB/GBL 45.3 50.0 46.7 38.3 Methamphetamine 43.0 50.0 43.7 37.3 Mephedrone 48.3 41.7 48.4 50.9 First sexualized drug in his lifec †,U,‡ Viagra 12.2 6.1 7.7 25.4 Poppers 53.6 52.8 55.5 49.6 Cannabis 19.6 31.1 20.4 11.9 Amphetamine 0.5 0.5 0.4 0.7 Cocaine 4.9 0.9 5.8 4.8 Ecstasy 2.6 2.4 2.5 3.1 Ketamine 0.2 0.5 0.2 0.0 GHB/GBL 3.1 2.4 3.9 1.7 Methamphetamine 1.5 1.9 1.8 0.7 Mephedrone 1.2 0.0 1.6 1.0 Drug most used as sexulized in his lifec †,U,‡ Viagra 12.1 4.3 8.1 25.2 Poppers 55.7 58.6 57.4 50.2 Cannabis 17.8 27.6 18.6 11.1 Amphetamine 0.6 0.5 0.7 0.5 Cocaine 4.5 0.5 4.7 5.9 Ecstasy 2.0 2.9 2.0 1.7 Ketamine 0.2 0.5 0.2 0.0 GHB/GBL 2.8 2.9 3.2 1.9 Methamphetamine 1.9 1.0 2.2 1.7 Mephedrone 1.8 0.5 2.3 1.2 Always/most of the time for sex in last 12 monthsc Cannabis 51.1 45.5 51.5 54.0 Amphetamine 52.9 60.0 47.2 68.2 Cocaine 46.8 35.3 43.5 58.4 Ecstasy 35.1 27.8 36.1 35.3 (Continued) Frontiers in Public Health 07 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 2 (Continued) All Age P-value <25 25–39 ≥40 Ketamine 52.9 50.0 52.2 55.9 GHB/GBL 67.6 73.9 66.9 66.7 Methamphetamine 78.3 81.3 73.0 91.6 ‡ Mephedrone 75.4 75.0 72.0 83.3 a MSM, men who have sex with men. b The percentages havebeen calculated on the total number of participants. c Thepercentages have been calculated on the number of participants who had consumed each substance to have sex. † p-value (<25 vs 25–39) <0.05; U p-value (<25 vs ≥40) <0.05; ‡ p-value (25–39 vs ≥40) <0.05. among the younger group, although these differences were not If we take as a reference the total number of users of statistically significant. a substance and not only those who have used it for SDU, Poppers were the first drug consumed as SDU for 53.6% the percentage for whom SDU was the first experience, the of all participants and for almost half in all three age groups, gateway to use, was logically lower: 40.8% for Mephedrone, followed by Cannabis (19.6%) and Viagra (12.2%). However, 35.7% for methamphetamine, 34.2% for GHB/GBL and 17.0% there were clear differences by age. While cannabis use was for ketamine, while for recreational drugs it was around 10%. more frequent among young people (31.1%), Viagra was more Most of the participants did not intentionally use for sex frequent among older people (25.4%). Less than 15% used any the three recreational drugs studied on their first sexualized of the other substances as a first drug, and the percentage use (irrespective of whether it had been consumed before was substantially lower among young people (8.5%), due to for recreational purposes or not), even if they ultimately the almost non-existent use of cocaine as a drug of sexualized had sex under the effect of these substances. In the case of initiation. The most commonly used SDU drugs were the same ecstasy, only 14.5% used it intentionally for sex. However, three that were most commonly used for first-time drug use, the situation was reversed with the 3-chems: 61.9% used with practically identical percentages. GHB intentionally for sex, as did 71.5% in the case of With the exception of ecstasy (35.1%), more than half of methamphetamine and 66.8% in the case of mephedrone. The those who had ever used each of the SDUs had always, or mode of drug acquisition in participants’ first SDU had a most often, used such drugs specifically for that purpose in the similar pattern to that of intentionality for sex: in the case of past 12 months. This proportion was substantially higher for recreational drugs, half or more of the subjects had acquired the three drugs most commonly associated with the chemsex them prior to having sex, while in the case of the 3-chems, phenomenon: GHB/GBL (67.6%), Mephedrone (75.4%) and more than 65% obtained them for free at the place where methamphetamine (78.3%), especially among those aged >40, they had sex. Only ketamine and methamphetamine showed where this proportion reached 91.6%. differences by age, with young people obtaining them free in the lowest proportion. Mephedrone was the drug that the highest percentage (8.5%) bought at the place where they had sex. Characteristics of the first episode of For participants’ first SDU, only 15–20% using recreational sexualized use drugs and less than 10% using three-chemsex drugs had sex only with their steady partner; the vast majority had sex with Between 23.1% and 28.0% of the participants with SDU, their casual partners or both. Among those who had sex with one first time using the three drugs considered most recreational or more occasional partners, between 26.2% and 34.6% of (amphetamine, cocaine and ecstasy) had been for sex, with recreational drug users did not use a condom with anyone, while no differences by age. Ketamine (41.9%) and GBH (56.6%) the percentage was over 40% for 4-chems. were in intermediate positions, while methamphetamine and mephedrone were used by about 70%. In addition, SDU was observed to take place quite early, as less than half of those who Correlates of sexualized use in the first had SDU did so after having used recreational drugs for other use purposes for at least 5 days. In the case of methamphetamine and mephedrone less than 16% did so. First-time sexualized use Supplementary Table 4 of the Annex shows the crude increased significantly with age for mephedrone (Table 3). results of the analysis. In the multivariate model (Table 4), Frontiers in Public Health 08 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 3 Characteristics of the first episode of sexualized use for different drugs by age among MSMa from Madrid and Barcelona. All Age P-value <25 25–39 ≥40 Purpose of the Sexualized use in the Amphetamine 28.0 25.0 28.3 28.2 b first use first use Cocaine 23.6 23.5 24.2 22.4 Ecstasy 23.1 13.5 24.6 23.6 Ketamine 41.9 42.9 40.3 46.3 GHB/GBL 56.6 65.9 52.5 64.6 Methamphetamine 69.6 61.5 70.6 70.6 Mephedrone 72.2 58.3 69.5 85.7 †, U Have used <5 days for Amphetamine 26.3 25.0 27.6 23.1 other purpose before Cocaine 30.1 26.5 30.8 29.6 first sexualized use Ecstasy 27.9 35.1 28.1 23.6 Ketamine 23.6 21.4 22.4 29.3 GHB/GBL 19.2 15.9 21.2 14.6 Methamphetamine 16.0 19.2 15.0 17.6 Mephedrone 12.0 8.3 13.6 8.9 †, U Have used >5 days for Amphetamine 45.7 50.0 44.1 48.7 other purpose before Cocaine 46.3 50.0 45.1 48.0 first sexualized use Ecstasy 48.9 51.4 47.3 52.8 Ketamine 34.5 35.7 37.3 24.4 GHB/GBL 24.2 18.2 26.3 20.7 Methamphetamine 14.3 19.2 14.4 11.8 Mephedrone 15.8 33.3 16.9 5.4 †, U Intentionally for sexb Amphetamine 23.8 20.0 21.4 33.3 Cocaine 27.1 23.5 25.0 32.5 Ecstasy 14.6 16.2 14.5 14.1 Ketamine 36.6 28.6 36.8 41.5 GHB/GBL 61.9 54.5 60.0 72.0 U Methamphetamine 71.5 65.4 72.3 72.0 Mephedrone 66.8 69.6 63.9 73.7 Mode of drug Had got the drug before Amphetamine 56.2 65.0 57.1 48.7 acquisitionb Cocaine 48.2 52.9 51.3 40.0 Ecstasy 63.0 75.7 62.7 57.1 Ketamine 39.8 53.6 41.7 24.4 U, ‡ GHB/GBL 30.3 39.5 28.1 32.1 Methamphetamine 16.2 19.2 15.2 18.0 † Mephedrone 24.7 37.5 24.7 19.3 Bought it where he had Amphetamine 2.7 5.0 2.4 2.6 sex Cocaine 2.8 5.9 2.2 3.2 Ecstasy 5.1 2.7 5.8 4.3 Ketamine 3.5 7.1 1.5 7.3 U, ‡ GHB/GBL 4.7 7.0 3.9 6.2 Methamphetamine 4.7 15.4 3.8 2.0 † Mephedrone 8.5 8.3 10.4 3.5 (Continued) Frontiers in Public Health 09 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 3 (Continued) All Age P-value <25 25–39 ≥40 Was given free where he Amphetamine 41.1 30.0 40.5 48.7 had sex Cocaine 49.1 41.2 46.5 56.8 Ecstasy 31.9 21.6 31.6 38.6 Ketamine 56.7 39.3 56.8 68.3 U, ‡ GHB/GBL 65.0 53.5 68.0 61.7 Methamphetamine 79.1 65.4 81.0 80.0 † Mephedrone 66.8 54.2 64.9 77.2 Had sex only with steady partnerb Amphetamine 14.5 5.0 16.5 12.8 Cocaine 17.7 20.6 14.8 23.6 ‡ Ecstasy 18.4 16.2 17.0 23.9 Ketamine 12.0 14.3 10.7 14.6 GHB/GBL 9.7 9.1 9.3 11.1 Methamphetamine 6.8 7.7 7.0 6.0 Mephedrone 8.1 16.7 7.1 7.1 Did not used a condom with any partnerc Amphetamine 34.6 26.3 33.0 44.1 Cocaine 27.2 37.0 27.5 23.4 Ecstasy 26.2 22.6 25.3 31.5 Ketamine 45.5 37.5 47.0 45.7 GHB/GBL 40.8 37.5 40.2 44.4 Methamphetamine 56.9 58.3 53.7 66.0 Mephedrone 50.2 45.0 49.7 53.8 a MSM, men who have sex with men. b The percentages have been calculated on the number of participants who had consumed each substance to have sex. c Thepercentages have been calculated on the number of participants who had consumed each substance for SDU with occasional partners (regardless of whether or not he also had sex with his steady partner) † p-value (<25; 25–39) <0.05; U p-value (<25; ≥40) <0.05; ‡ p-value (25–39; ≥40) <0.05. sexualized use in the first use, in the case of party drugs, Discussion was associated with being tested in Barcelona and having been born in Latin America, whereas chemsex drugs were Main findings associated with being recruited in STI diagnostic center. The other associated factors were common for both kind To our knowledge, this is the first study that jointly analyzes of drugs. The most strongly associated factor was having drug use for any purpose and for sex (SDU) among MSM. It is been penetrated by more than 20 men in one’s lifetime, also the first study to analyze to what extend SDU has served in which aPRs were around five for both kind of drugs, as the gateway to drug use, the first consumption experience for followed by ever injected drugs [(aPR: 4.0; 95% CI:3.1–5.0, different drugs, and various characteristics of the first sexualized for chemsex drugs) and (aPR 2.0; 95% CI:1.2–3.3, for party consumption of these drugs. drugs)]. The remaining factors (met the largest number of Thus, this study represents the first time it has been possible partners at discos/bars-saunas-private parties, ever having been to provide empirical evidence that, among MSM, SDU is paid for sex, ever injected steroids and ever diagnosed with one of the most prevalent motivations or contexts for drug an STI) showed similar aPRs in both populations, of between consumption, especially Viagra, poppers, cocaine and chemsex 1.4 and 1.5. drugs, for which the prevalence of SDU is close to or above Frontiers in Public Health 10 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 TABLE 4 Multivariate regression analysis of associated factors with sexualized use in the first use for recreational drugs and for chemsex drugs. Sexualized use in the first use for Sexualized use in the first use for recreational drugs1 chemsex drugs2 aPR* CI 95%** aPR CI 95% City of testing Madrid 1.0 Barcelona 1.5 1.1–2.0 Kind of testing program Comunity program 1.0 STI diagnostic center 1.3 1.1–1.6 Country of birth Spain 1.0 Latin America 1.6 1.2–2.2 Others 1.3 0.8–2.0 Lives sex life with men Not openly 1.0 1.0 Openly 1.3 0.9–1.8 1.3 1.0–1.6 Place where the largest number of partner were found Others 1.0 1.0 Discos/bars-saunas-private parties 1.8 1.3–2.4 1.7 1.4–2.1 Number of men who had penetrated you (ever) None-one 1.0 1.0 2–20 4.3 1.4–13.5 3.2 1.4–7.2 >20 4.9 1.5–15.4 5.0 2.2–11.2 Ever been paid for sex No 1.0 1.0 Yes 1.4 1.1–1.9 1.5 1.2–1.8 Ever injected drugs No 1.0 1.0 Yes 2.0 1.2–3.3 4.0 3.1–5.0 Ever injected steroids No 1.0 1.0 Yes 1.6 1.1–2.5 1.5 1.2–2.0 Ever diagnosed with an STI No 1.0 1.0 Yes 1.5 1.1–2.0 1.8 1.4–2.3 1 Amphetamine, cocaine or ecstasy. 2 Ketamine, GHB/GBL, methamphetamine or mephedrone. Bold values indicate that the adjusted prevalence ratio is significant. * Adjusted prevalence ratio. ** 95% confidence interval. 50% of the prevalence of use for any purpose, both during prevalence. While it is clear that the lifetime prevalence of one’s lifetime and in the past 12 months. In contrast, it has younger people may be more likely to increase, the data been confirmed that hallucinogens, sedatives and opiates are suggest that the phenomenon of increased sexualization of use not generally used for SDU. We have used the word “gateway,” has perhaps begun years ago. An analysis carried out by the referring only to the first experience with different drugs, 2012 EMIS Study (5) showed a decline by age in recent 4- without any related meaning with the classical gateway drug chem prevalence. effect or stepping-stone theory (37). The age group with the This study shows, also for the first time, that SDU serves as lowest lifetime prevalences of SDU for almost all drugs was the first experience of drug use; it is the gateway to consumption people under 25, while those aged 25–39 have the highest for more than one in three users of methamphetamine, Frontiers in Public Health 11 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 mephedrone and GHB. This is also the case for about 1 However, many studies analyze the use of these substances as in 10 users of the recreational drugs: cocaine, ecstasy and if all users were using them for sex (5). It is quite possible that amphetamine. Among MSM with SDU, these percentages poppers, and especially Viagra, are often consumed with the double or triple, depending on the drug. In addition to those who thought that sexual intercourse will most likely take place under consumed directly through SDU, another significant percentage their effect, but then this does not happen. On the other hand, of individuals entered SDU very early (having used less than recreational drugs are most likely taken in a recreational setting five times for other purposes). The drugs most commonly used where sex is often involved, but the drugs are not intentionally during the first episode of SDU were the three that were most taken for that purpose. In this study the percentage who had prevalent for SDU: poppers (in more than half of the cases), intentionally taken them for sex at the first SDU was less than cannabis (one in five), and Viagra (just over 1 in 10), although 30%. However, all three chem drugs are taken intentionally for the order of these last two substances was reversed in the case sex on most occasions by those who have used them for SDU, of those over age 40. This study also suggests that the context most likely in the context of organized chemsex sessions. of the first sexualized use is very different for recreational drugs Being recruited in Barcelona and being born in Latin compared to chemsex drugs. The former are obtained in greater America was associated with having consumed any of the three proportion before having sex, while chemsex drugs are obtained recreational drugs analyzed for SDU, which could be explained in the same place where sex is carried out, mostly provided as by cultural differences that promote greater sexualization of gifts, thus facilitating entry into consumption. It is also clear that these drugs with respect to those born in Spain and residing this consumption usually takes place in contexts of sexual risky in Madrid. The association between sexualized initiation of behaviors, since it is rare to have sex only with a stable partner, chemsex drugs and being recruited in STI diagnostic centers is rather it is common to have sex with occasional partners and most likely due to the fact that these centers serve a population with more than one person for a high percentage of individuals, with more risky behaviors. All other correlates were common for especially in the case of chemsex drugs. In addition, more than recreational and chemsex drugs. Those whose sexual behavior one in four (for recreational drugs) and nearly half or more (for is more open had a higher risk, as well as those who find their chemsex drugs) do not use a condom with any sexual partner. partners mainly in discos, bars and private parties. This finding This suggests that, from the beginning, there is a “risk ladder” in is surprising because the chemsex phenomenon has always been terms of risky behavior (10) depending on the drug type. related to the ease of contact through dating apps, which was Poppers, cannabis and Viagra were the substances that in fact the most frequent way of obtaining partners among participants had used most often in a sexualized way in their the participants. It is possibly due to the fact that SDU at lifetime. It should be noted that among those who have ever used first use occurs among those who frequent such environments a substance for SDU, this type of use becomes the predominant for possibly all recreational drugs, and also for some chemsex context for their use. This is because, with the exception of drugs. However, the correlates with the strongest association ecstasy, more than half had used the substance always or most were common for recreational and chemsex drugs, and all were of the time for sex in the last year. There are currently no other indicators of risk behaviors. Having been penetrated by more studies that corroborate this finding, because other studies, such than 20 men in life, ever having injected drugs and ever having as the EMIS study, have not used this approach. Rather, they been diagnosed with an STI (especially for chemsex drugs) have focused analysis on the percentage of sober sex (35). It is are worth highlighting. This association with risk behaviors also worth noting that more than half of those whose first use was to be expected, especially for chemsex drugs. Since it is of recreational drugs was for SDU also used chemsex drugs. already known that such an association exists for those who However, less than a third of those who used chemsex drugs for have practiced SDU (10, 18, 34, 38), it is logical that it would SDU the first time also used recreational drugs. This finding can be found among people who start using those drugs for sex. be explained by the fact that, as we have pointed out, entry into That the strongest correlates are common to both drugs seems chemsex use for the purpose of SDU is much more frequent. In logical, since, as we have pointed out, a large percentage began addition, it is possible that there is a time sequence that begins consumption as SDU for both types of drugs. with SDU use of recreational drugs, however we cannot confirm this, because we did not ask about the age of onset. The study also shows, for the first time, that drugs that Limitations are assumed to always be consumed for sex (Viagra) or almost always (poppers), are actually consumed on quite a few As in most studies in MSM, this study employed occasions without sex. In fact, in this study we did not ask convenience sampling, here MSM accessing HIV testing. A whether the first use of these two substances was sexualized or sample of significant size was recruited, and two programs not, since we assumed that it was practically always sexualized. with very different client recruitment characteristics (one This phenomenon is even more relevant in the case of chemsex health center and one community program) were chosen drugs, since nearly half had not used them for this purpose. in each city in order to increase the sample’s heterogeneity Frontiers in Public Health 12 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 and representativeness. Still, caution should be exercised in neither level of education nor economic status was found to generalizing results among MSM, because convenience samples have an association, while openly living one’s sexual life as tend to sample higher-risk MSM than do general population gay was. surveys (39, 40). However, this bias could be partly compensated In this context, it is important to reinforce the informative, for the fact that HIV positive men were not included, and it preventive and harm reduction initiatives that are already being is known that this group presents higher levels of drug use implemented in various countries and that take into account than those who are HIV-negative (5, 41, 42). Secondly, the the interventions suggested by MSM themselves (44–47). It participants came only from the Madrid and Barcelona areas. is important not to forget the challenge posed by the likely These are the two most populated areas in Spain and have higher existence of culture that is counter to public health. As a recent prevalences of MSM, because they attract MSM from other parts study in Australia has shown, this culture has been found to of Spain and abroad. Previous studies have shown that they are be underpinned by forms of “sex-based sociality,” which gives among the European cities with the highest SDU prevalences primacy to the priorities and practices of gay and bisexual men (5, 34). It is probable that their prevalences are higher than (48). It would also be useful to have information similar to that other less populated areas of Spain, as has also been described in collected here for the general population, since the prevalence of other countries (43). Thirdly, the presence of social desirability SDU for the different substances is unknown, as is whether SDU bias could be thought to compromise the validity of socially acts as a privileged gateway to consumption. disapproved behaviors. However, the collection of information through an anonymous, self-administered questionnaire tends to reduce such bias compared to telephone or face-to-face interviews, since it preserves to a greater extent the privacy Data availability statement of responses to questions of a more sensitive nature. Finally, in order to make it easier for participants to answer the The original contributions presented in the study are questionnaire, the same time period was used to define included in the article/Supplementary materials, further sexualized use (6 h). This may have led to some overestimation inquiries can be directed to the corresponding author/s. of SDU for some substances with shorter half-lives (such as poppers or mephedrone), although it is common for these substances to be taken repeatedly, before or during sex. The methysos project group María del Carmen Burgos and César Pérez Romero (Instituto de Salud Carlos III, Madrid); José Antonio San Conclusions and policy and research Juan Bueno (Asociación Pink Peace, Madrid); Francisca Román implications Urrestarazu, Jesus E. Ospina, and Miguel Alarcón Gutiérrez (Agència de Salut Pública de Barcelona, Barcelona); Jorge del Prevalence of SDU was more than half of the prevalence Romero, Carmen Rodríguez, Sonsoles del Corral Del Campo, of drug use for any purpose. Thus, SDU acts as the gateway Natividad Jerez Zamora, Marta Ruiz Fernández, and Montserrat to use for many drugs in an important proportion of users, González Polo (Centro Sanitario Sandoval, Madrid); María Jesús who frequently have their first consumption experience using Barbera Gracia, Luis López Pérez, Claudia Broto Cortes, and free drugs while having condomless, anal sex with occasional Julio Morais Martin (UITS Drassanes, Barcelona). and multiple partners. In addition, among 50% or more of those who had SDU, this context of consumption was the predominant one, accounting for drug use always or most of the time during the past year. These circumstances were much Author contributions more common for chemsex than for recreational drugs. It is highly probable that the popularization of some substances LF, PG, and M-JB conceived, designed, and supervised the used primarily for SDU (especially methamphetamine and study. J-MG and DD organized the recruitment of participants. mephedrone) will facilitate their use for recreational purposes J-MG, MD, DD, OA, and JG-P contributed to the recruitment of in this same population. MSM could serve as a bridge, bringing subject and data collection. J-MG, JH, MD, and DD performed these drugs to the general population, where their use is the main analyzes. J-MG, JH, LF, PG, and M-JB wrote the currently very low. Beginning substance use directly through manuscript. JH, LF, and M-JB were responsible for drafting and SDU was found to be associated with a higher level of critical revisions of the manuscript. J-MG, JH, MD, LF, DD, OA, both sexual and injection risk behaviors, suggesting that we JG-P, PG, M-JB, and the additional members of the Methysos are dealing with a population that is particularly vulnerable Project Group made substantive contributions to the current to infectious diseases transmitted by these routes. However, article. All authors read and approved the final manuscript. Frontiers in Public Health 13 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 Funding that could be construed as a potential conflict of interest. This study was supported by the Delegación del Gobierno para el Plan Nacional sobre Drogas (2019I017). Publisher’s note All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated Acknowledgments organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or The authors are grateful to Pink Peace whose rapid claim that may be made by its manufacturer, is not guaranteed HIV testing program was responsible for the recruitment of or endorsed by the publisher. participants in Madrid. Supplementary material Conflict of interest The Supplementary Material for this article can be found The authors declare that the research was conducted in online at: https://www.frontiersin.org/articles/10.3389/fpubh. the absence of any commercial or financial relationships 2022.997730/full#supplementary-material References 1. Edmundson C, Heinsbroek E, Glass R, Hope V, Mohammed H, White M, et al. 12. Han B, Compton WM, Jones CM, Einstein EB, Volkow Sexualised drug use in the United Kingdom (UK): a review of the literature. Int J ND. Methamphetamine use, methamphetamine use disorder, and Drug Policy. (2018) 55:131–48. doi: 10.1016/j.drugpo.2018.02.002 associated overdose deaths among US adults. JAMA Psychiatry. (2021) 78:1329–42. doi: 10.1001/jamapsychiatry.2021.2588 2. Maxwell S, Shahmanesh M, Gafos M. Chemsex behaviors among men who have sex with men: a systematic review of the literature. Int J Drug Policy. (2019) 13. Incera-Fernandez D, Gamez-Guadix M, Moreno-Guillen S. Mental health 63:74–89. doi: 10.1016/j.drugpo.2018.11.014 symptoms associated with sexualized drug use (Chemsex) among men who have sex with men: a systematic review. Int J Environ Res Public Health. (2021) 3. Hibbert MP, Hillis A, Brett CE, Porcellato LA, Hope VD. A narrative 18:13299. doi: 10.3390/ijerph182413299 systematic review of sexualised drug use and sexual health outcomes among LGBT people. Int J Drug Policy. (2021) 93:103187. doi: 10.1016/j.drugpo.2021.10 14. Bohn A, Sander D, Kohler T, Hees N, Oswald F, Scherbaum N, et al. Chemsex 3187 and mental health of men who have sex with men in Germany. Front Psychiatry. (2020) 11:542301. doi: 10.3389/fpsyt.2020.542301 4. Guerra FM, Salway TJ, Beckett R, Friedman L, Buchan SA. Review 15. Hockenhull J, Murphy KG, Paterson S. An observed rise in gamma- of sexualized drug use associated with sexually transmitted and blood-borne hydroxybutyrate-associated deaths in London: evidence to suggest a possible infections in gay, bisexual and other men who have sex with men. Drug Alcohol link with concomitant rise in chemsex. Forensic Sci Int. (2017) 270:93– Depend. (2020) 216:108237. doi: 10.1016/j.drugalcdep.2020.108237 7. doi: 10.1016/j.forsciint.2016.11.039 5. Schmidt AJ, Bourne A, Weatherburn P, Reid D, Marcus U, Hickson 16. Corkery JM, Loi B, Claridge H, Goodair C, Schifano F. Deaths in F. Illicit drug use among gay and bisexual men in 44 cities: findings from the lesbian, gay, bisexual and transgender United Kingdom communities the European MSM internet survey (EMIS). Int J Drug Policy. (2016) 38:4– associated with GHB and precursors. Curr Drug Metab. (2018) 19:1086– 12. doi: 10.1016/j.drugpo.2016.09.007 99. doi: 10.2174/1389200218666171108163817 6. McCall H, Adams N, Mason D, Willis J. What is chemsex and why does it 17. Sewell J, Cambiano V, Speakman A, Lampe FC, Phillips A, Stuart D, et al. matter? BMJ. (2015) 351:h5790. doi: 10.1136/bmj.h5790 Changes in chemsex and sexual behavior over time, among a cohort of MSM in 7. Public Health England. Sustance Misuse Services for Men Who have Sex London and Brighton: findings from the AURAH2 study. Int J Drug Policy. (2019) with Men Involved in Chemsex. (2015). Available online at: https://www.gov.uk/ 68:54–61. doi: 10.1016/j.drugpo.2019.03.021 government/uploads/system/uploads/attachment_data/file/669676/Substance_ 18. Gonzalez-Baeza A, Dolengevich-Segal H, Perez-Valero I, Cabello A, Tellez misuse_services_for_men_who_have_sex_with_men_involved_in_chemsex.pdf MJ, Sanz J, et al. Sexualized drug use (Chemsex) is associated with high-risk sexual (accessed June 1, 2022). behaviors and sexually transmitted infections in HIV-positive men who have sex 8. Stuart D. Chemsex: origins of the word, a history of the with men: data from the U-SEX GESIDA 9416 study. AIDS Patient Care STDS. phenomenon and a respect to the culture. Drugs Alcohol Today. (2019) (2018) 32:112–8. doi: 10.1089/apc.2017.0263 19:3–10. doi: 10.1108/DAT-10-2018-0058 19. Lee CY, Wu PH, Chen TC, Lu PL. Changing pattern of chemsex 9. Wang Z, Mo PKH, Ip M, Fang Y, Lau JTF. Uptake and willingness to drug use among newly diagnosed HIV-positive Taiwanese from 2015 to use PrEP among Chinese gay, bisexual and other men who have sex with men 2020 in the era of treat-all policy. AIDS Patient Care STDS. (2021) 35:134– with experience of sexualized drug use in the past year. BMC Infect Dis. (2020) 43. doi: 10.1089/apc.2020.0246 20:299. doi: 10.1186/s12879-020-05024-4 20. Sang JM, Cui Z, Sereda P, Armstrong HL, Olarewaju G, Lal A, et al. 10. Guerras JM, Hoyos J, Agusti C, Chanos S, Pichon F, Kuske M, et al. Longitudinal event-level sexual risk and substance use among gay, bisexual, and Association of sexualized drug use patterns with HIV/STI transmission risk in an other men who have sex with men. Int J Environ Res Public Health. (2021) internet sample of men who have sex with men from seven European countries. 18:3183. doi: 10.3390/ijerph18063183 Arch Sex Behav. (2021) 50:461–77. doi: 10.1007/s10508-020-01801-z 21. Flores Anato JL, Panagiotoglou D, Greenwald ZR, Blanchette 11. Wang Z, Yang X, Mo PKH, Fang Y, Ip TKM, Lau JTF. Influence of social M, Trottier C, Vaziri M, et al. Chemsex and incidence of sexually media on sexualized drug use and chemsex among Chinese men who have sex transmitted infections among Canadian pre-exposure prophylaxis (PrEP) with men: observational prospective cohort study. J Med Internet Res. (2020) users in the l’Actuel PrEP cohort (2013–2020). Sex Transm Infect. (2022) 22:e17894. doi: 10.2196/17894 055215. doi: 10.1136/sextrans-2021-055215. [Epub ahead of print]. Frontiers in Public Health 14 frontiersin.org Guerras et al. 10.3389/fpubh.2022.997730 22. Colfax G, Vittinghoff E, Husnik MJ, McKirnan D, Buchbinder S, Koblin 36. Espelt A, Mari-Dell’Olmo M, Penelo E, Bosque-Prous M. Applied B, et al. Substance use and sexual risk: a participant—and episode-level analysis prevalence ratio estimation with different regression models: an example from among a cohort of men who have sex with men. Am J Epidemiol. (2004) 159:1002– a cross-national study on substance use research. Adicciones. (2016) 29:105– 12. doi: 10.1093/aje/kwh135 12. doi: 10.20882/adicciones.823 23. Ober A, Shoptaw S, Wang PC, Gorbach P, Weiss RE. Factors associated 37. Vanyukov MM, Tarter RE, Kirillova GP, Kirisci L, Reynolds MD, Kreek with event-level stimulant use during sex in a sample of older, low-income men MJ, et al. Common liability to addiction and “gateway hypothesis”: theoretical, who have sex with men in Los Angeles. Drug Alcohol Depend. (2009) 102:123– empirical and evolutionary perspective. Drug Alcohol Depend. (2012) 123 Suppl 9. doi: 10.1016/j.drugalcdep.2009.02.002 1:S3–17. doi: 10.1016/j.drugalcdep.2011.12.018 24. Halkitis PN, Green KA, Mourgues P. Longitudinal investigation of 38. Glynn RW, Byrne N, O’Dea S, Shanley A, Codd M, Keenan E, et al. methamphetamine use among gay and bisexual men in New York City: Chemsex, risk behaviors and sexually transmitted infections among men who findings from project BUMPS. J Urban Health. (2005) 82(1 Suppl 1):i18– have sex with men in Dublin, Ireland. Int J Drug Policy. (2018) 52:9– 25. doi: 10.1093/jurban/jti020 15. doi: 10.1016/j.drugpo.2017.10.008 25. Buchacz K, McFarland W, Kellogg TA, Loeb L, Holmberg SD, Dilley 39. Schwarcz S, Spindler H, Scheer S, Valleroy L, Lansky A. Assessing J, et al. Amphetamine use is associated with increased HIV incidence among representativeness of sampling methods for reaching men who have sex with men: men who have sex with men in San Francisco. AIDS. (2005) 19:1423– a direct comparison of results obtained from convenience and probability samples. 4. doi: 10.1097/01.aids.0000180794.27896.fb AIDS Behav. (2007) 11:596–602. doi: 10.1007/s10461-007-9232-9 26. Chesney MA, Barrett DC, Stall R. Histories of substance use and risk 40. Prah P, Hickson F, Bonell C, McDaid LM, Johnson AM, Wayal S, et al. behavior: precursors to HIV seroconversion in homosexual men. Am J Public Men who have sex with men in Great Britain: comparing methods and estimates Health. (1998) 88:113–6. doi: 10.2105/AJPH.88.1.113 from probability and convenience sample surveys. Sex Transm Infect. (2016) 92:455–63. doi: 10.1136/sextrans-2015-052389 27. Drumright LN, Little SJ, Strathdee SA, Slymen DJ, Araneta MR, Malcarne VL, et al. Unprotected anal intercourse and substance use among men who have 41. Guerras JM, Hoyos J, Agusti C, Casabona J, Sordo L, Pulido J, et al. Substance sex with men with recent HIV infection. J Acquir Immune Defic Syndr. (2006) use in sexual context among Spanish resident men who have sex with men. 43:344–50. doi: 10.1097/01.qai.0000230530.02212.86 Adicciones. (2022) 34:37–49. doi: 10.20882/adicciones.1371 28. Stall R, Wiley J. A comparison of alcohol and drug use patterns of homosexual 42. Melendez-Torres GJ, Bourne A, Reid D, Hickson F, Bonell C, Weatherburn and heterosexual men: the San Francisco men’s health study. Drug Alcohol Depend. P. Typology of drug use in United Kingdom men who have sex with men and (1988) 22:63–73. doi: 10.1016/0376-8716(88)90038-5 associations with socio-sexual characteristics. Int J Drug Policy. (2018) 55:159– 64. doi: 10.1016/j.drugpo.2018.01.007 29. Hirshfield S, Remien RH, Walavalkar I, Chiasson MA. Crystal methamphetamine use predicts incident STD infection among men who 43. Achterbergh RCA, Druckler S, van Rooijen MS, van Aar F, have sex with men recruited online: a nested case-control study. J Med Internet Slurink IAL, de Vries HJC, et al. Sex, drugs, and sexually transmitted Res. (2004) 6:e41. doi: 10.2196/jmir.6.4.e41 infections: a latent class analysis among men who have sex with men 30. Plankey MW, Ostrow DG, Stall R, Cox C, Li X, Peck JA, et al. The relationship in Amsterdam and surrounding urban regions, the Netherlands. Drug between methamphetamine and popper use and risk of HIV seroconversion in Alcohol Depend. (2020) 206:107526. doi: 10.1016/j.drugalcdep.2019. the multicenter AIDS cohort study. J Acquir Immune Defic Syndr. (2007) 45:85– 06.028 92. doi: 10.1097/QAI.0b013e3180417c99 44. Ministerio de Sanidad, Secretaría del Plan Nacional sobre el Sida. Documento 31. Compton WM, Jones CM. Substance use among men who have sex with men. Técnico sobre Abordaje del Fenómeno del Chemsex. (2020). Available online N Engl J Med. (2021) 385:352–6. doi: 10.1056/NEJMra2033007 at: https://www.sanidad.gob.es/ca/ciudadanos/enfLesiones/enfTransmisibles/sida/ chemSex/docs/DocumentoDEF.pdf (accessed June 1, 2022). 32. Halkitis PN, Parsons JT, Stirratt MJ. A double epidemic: crystal methamphetamine drug use in relation to HIV transmission among gay men. J 45. Bourne A, Ong J, Pakianathan M. Sharing solutions for a reasoned and Homosex. (2001) 41:17–35. doi: 10.1300/J082v41n02_02 evidence-based response: chemsex/party and play among gay and bisexual men. Sex Health. (2018) 15:99–101. doi: 10.1071/SH18023 33. Green AI, Halkitis PN. Crystal methamphetamine and sexual sociality in an urban gay subculture: an elective affinity. Cult Health Sex. (2006) 8:317– 46. Stardust Z, Kolstee J, Joksic S, Gray J, Hannan S. A community-led, harm- 33. doi: 10.1080/13691050600783320 reduction approach to chemsex: case study from Australia’s largest gay city. Sex Health. (2018) 15:179–81. doi: 10.1071/SH17145 34. Rosinska M, Gios L, Nostlinger C, Vanden Berghe W, Marcus U, Schink S, et al. Prevalence of drug use during sex amongst MSM in Europe: results 47. London Friend. Real Chemistry—Connection, Wellbeing and Chemsex from a multi-site bio-behavioral survey. Int J Drug Policy. (2018) 55:231– Recovery. (2021). Available online at: https://londonfriend.org.uk/wp-content/ 41. doi: 10.1016/j.drugpo.2018.01.002 uploads/2021/03/RealChemistryManual.pdf (accessed June 1, 2022). 35. EMIS Network. EMIS-2017—The European Men-Who-Have-Sex-With- 48. Drysdale K, Bryant J, Dowsett GW, Lea T, Treloar C, Aggleton P, et al. Men Internet Survey. Key Findings from 50 Countries. (2019). Available Priorities and practices of risk reduction among gay and bisexual men in online at: https://www.ecdc.europa.eu/sites/default/files/documents/European- Australia who use crystal methamphetamine for sex. Int J Drug Policy. (2021) MSM-internet-survey-2017-findings.pdf (accessed June 1, 2022). 93:103163. doi: 10.1016/j.drugpo.2021.103163 Frontiers in Public Health 15 frontiersin.org