Sexualised drug use and chemsex in Italy: A questionnaire study based on a cohort of clients attending a STI outpatient service in Milan

Abstract

Background

Chemsex is a heterogeneous phenomenon with differences in distribution, setting, motivations and type of substances consumed between countries. The lack of data at national level of the Italian situation creates a perception of reduced need for intervention.

Methods

Anonymous paper questionnaires were distributed to patients who had registered themselves at the STI Department IRCCS Ca’ Granda Policlinico in Milan.

Results

A significant association was demonstrated between use of sexualised drugs, chemsex and the following variables: (1). Number of partners: in the group of clients with more than five partners, sexualised drug users were more than twice compared with those in the group with less than five partners (35.2% vs 16.2%) p<0.0001. (2). Use of dating apps: more than one out of two persons who used drugs during sex affirmed looking for partners on internet, p = 0.0059. (3). Low condom uses with occasional partners: percentage of individuals who declared not to use condoms or devices during their sexual encounters with occasional partners is more than twice as high in the sexualised drug users group with respect to controls (44.6% vs 21.4%); p = 0.0006). (4). Use of post exposure prophylaxis (PEP): among the PEP users, more than half participants belonged to the sexualised drug users’ group; p = 0.0021.

Conclusions

Sexualised drug use and chemsex are frequently practiced in Milan. This survey identified a specific population with higher-risk sexual behaviours and increased incidence of acute bacterial STIs.

Keywords

Chemsex STI sexual behavior syphilis gonorrhoea chlamydia

Introduction

The term “Chemsex” is used to describe the intentional intake, during sex, of specific drugs to enhance sexual performances and/or prolong their duration. Crystal methamphetamine, cathenones (mephedrone, 3MMC, 4MMC) and GHB/GBL (gammahydroxubutyrate/gammabutyrolactone) are classically referred to as the main “chems”: these stimulants enhance sexual arousal feelings and disinhibition. However, Viagra, alcohol, ketamine, cocaine, amyl/alkyl nitrates (poppers) can be also involved as additional drugs. These substances, especially when mixed, can alter an individual's decision-making capacity. Stuart identified several cultural factors contributing to the spread of chemsex among men who have sex with men (MSM). These factors include HIV and AIDS stigma, homonegativity, religious attitudes towards homosexuality, and the prevalent use of dating apps to find sexual partners.¹

Scientific literature shows that chemsex is associated with sexual acts (e.g., orgies, sex parties, prolonged sexual sessions, fisting), which often take place without the use of protective devices such as condoms.² This identifies a category of patients who is more susceptible to common sexually transmitted infections (STIs). Moreover, drug use involves complications related to abuse and modality of substance consumption (e.g., sharing syringes).³ For the above-listed reasons, numerous studies underline the need to consider the phenomenon a public health priority.⁴

Epidemiologic data show that in northern Europe and in the USA chemsex is a widespread practice;^5–7 however, despite the classical definition, chemsex is a heterogeneous phenomenon with differences in distribution, setting, motivations and type of substances consumed between countries. The recent “Chems4EU” internet Survey Report showed that 11.9% (19/159) of Italian MSM had a chemsex experience in the last year. Data were collected from a group of 1589 HIV‐positive MSM of four different countries (UK, Spain, Italy and Greece) through a wide online survey.⁸ Moreover, Nimbi et al, investigating contexts and substances used in a small group of 30 Italian MSM chemsex practitioners, found some important peculiarities of the phenomenon. Chemsex was mainly undertaken in private homes with couples or groups of sexual activities. Cocaine was the most relevant substance consumed with “chems” followed by a large use of phosphodiesterase type 5 inhibitors. Finally, the study reported that slamming was rarely described among the participants.⁹

The lack of data at national level of the Italian situation creates a perception of a reduced need for intervention. Inexperience of healthcare professionals and service providers can lead to inadequate or inappropriate care, as well as a failure to provide targeted interventions and preventive measures, therefore we proposed our study.

The purpose of the analysis was to assess the prevalence of the sexualised drug use and chemsex in the population attending the dedicated STI outpatient service of the IRCCS Foundation Ca’ Granda Ospedale Maggiore Policlinico of Milan and analyse the relationship between some individual characteristics and the phenomenon.

Material and method

Study population

The study population consisted of male and female clients, with different self-reported sexual orientations, attending the dedicated STI outpatient service of the IRCCS Foundation Ca’ Granda Ospedale Maggiore Policlinico of Milan. The requirements to be part of the study were (i) being over 18; (ii) having had sex in the previous 12 months, (iii) ability to read and understand Italian.

Data collection

In the period between 1 July 2021 and 31 January 31 2022, paper questionnaires were distributed by doctors to patients who had registered themselves at the STI Department. After a brief explanation about chemsex, those who accepted to participate in the study self-completed the form anonymously and then left it in a locked box in the waiting room. No incentive was offered to participants in exchange for participation.

The questionnaire

The research team designed a 26-multiple choice question survey written in the Italian language. No data involving personal identification were collected. Items were grouped into four major categories: sociodemographic data (age, gender, educational level, employment status, sexual orientation), STI history, sexual risk behaviours (testing history, number of sexual partners, participating in sex parties or orgies, use of condoms with occasional and stable partners, frequency of dating app use) and chemsex experiences. STI history was collected as a reported diagnosis of the following infections: Syphilis, Gonorrhoea, Chlamydia, HIV, genital warts, molluscum contagiosum, Hepatitis B, Hepatitis C. Chemsex experiences were assessed in terms of frequency, type of drugs (including slamming), hospitalization requirement, reasons and place of practice, modality of finding partners, use of condoms and wish to discontinue drug use. All participants were asked to select which drugs they had used during sex from the following list: Methamphetamine, GHB/GBL, Mephedrone, Cocaine, Ketamine, Cannabis, Poppers, Sildenafil and Others; where “others” was selected, participants had to specify the drugs by free text.

All questions were referred to the previous 12 months. Finally, to validate the questionnaire, we conducted a pilot study among 30 patients who were not included in the data analysis.¹⁰

Ethics

This study was conducted in accordance with the protocol, the rules of the ICH/GCP (International Conference of Harmonization/Good Clinical Practice) and all applicable laws, including the Declaration of Helsinki of June 1964, as amended by the last World Medical Association General Assembly in Seoul, 2008. The study was approved by the Institutional Ethics Committee. The patients in this manuscript have given written informed consent to publication of their case details.

Study endpoints

Primarly, this study aimed to investigate and determine the prevalence of sexualised drug usage and chemsex in the individuals attending the dedicated STI outpatient service of the IRCCS Foundation Ca’ Granda Ospedale Maggiore Policlinico of Milan.

Secondary endpoints included analysis of sociodemographic data, STI history and sexual risk behaviours to determine main characteristics associated with chemsex use. Finally, within the sexualised drug users we analysed differences between male and female participants in terms of frequency, type of drugs, hospitalization requirement, reasons and place of practice, modality of finding partners, use of condoms and desire to discontinue drug use.

Data analysis

Categorical variables are presented as counts and percentages, while the continuous variables are expressed as medians and interquartile ranges (IQR).

The prevalence of sexualised drug users, with 95% confidence interval (CI), was calculated for the overall population and for some pre specified subgroups defined according to sociodemographic characteristics, STI history and sexual habits. Comparisons between subgroups were performed with Fisher’s exact test for categorical variables and with Wilcoxon two-sample test for continuous variables. Statistical significance was defined as p value ≤0.05, two sided. All statistical analyses were performed with SAS software V.9.4 (SAS Institute, Cary, NC, USA).

Results

From 1 July 2021 to 31 January 2022, 2135 clients attended the STI Department of our hospital. Among these, 534 (25.0%) persons accepted to complete the questionnaire. The majority had higher education (64.0% - 342/534), were in employment (73.0% - 390/534), and the median age was 29 years (IQR, 24-35). Among the 534 enrolled subjects, 132 (24.7%, 95% CI 21.8%- 28.6%) reported having had recreational drug use during sex in the last year – 107 men and 25 women. Of those, 57.6% (76/132) declared having a LGBQT+ sexual orientation versus 42.4% (56/132) of heterosexuals. 74% (98/132) of the participants used substances more than once and 48% (63/132) of them were hesitant about discontinuing drug use. Finally, less than 3% (16/534) of clients were people living with HIV (4.5% in drug users and 2.4% in non-users).

Altogether, Methamphetamine, GHB/GBL, Ketamine and Mephedrone were used by 39.1% (52/132) of participants who had engaged in chemsex. Cocaine was more frequently used as unique sex-related-drug by heterosexual subject (76.5% - 13/17) compared to LGBQT+ (48.1% - 13/27). Cannabis consumption prevailed in the female (60% - 15/25) group and was often used in combination with other drugs. In total, 22% (29/132) of participants used multiple substances.

56.8% (75/132) of participants declared using dating apps to find chemsex partners. Private homes represented the preferred place to practise chemsex in most cases (73.5% - 97/132). Moreover, 39.4% of practisers had sex in groups and less than half declared to use condoms during sessions (47.7% - 63/132).

A significant association was demonstrated between use of sexualised drugs, chemsex and the following variables (Table 1):

1. Number of partners: the percentage of sexualised drug users among group of clients with more than five partners is 35.2% versus 16.2% in the group who had less than five partners; p<0.0001.

2. Use of dating apps: prevalence of sexualised drug users varies from 31.1% in the group of clients who declared to always use app to find sexual partners, compared to 27.2% of those who use them sometimes versus 18.2% of those who never use them; p = 0.0059.

3. Low condom uses with occasional partners: the percentage of sexualised drug users is significantly higher among clients who never use them compared to people who always use them (44.6% vs 21.4%); p = 0.0006).

4. Use of post exposure prophylaxis (PEP): 55.0% of patient who used PEP at least once declared to use sexualised drugs versus 23.4% in the other group; p = 0.0021.

Table 1.

Sociodemographic, STI history and sexual habits in total and percentage reported in the previous 12 months by sexualized drug users and chemsex practitioners of STI Department Ca Grande Policlinico Hospital in Milan who answered the questionnaire on chemsex (July 2021–January 2022). n/N stands for the number of sexualised drug users and chemsex practitioners on total of clients that participated in the study.

Variables	Users		p value
Variables	n/N	Percent (95% CI)	p value
Sex
M	107/399	26.8% (22.5% – 31.5%)	0.0644
F	25/135	18.5% (12.4% – 26.1%)	0.0644
Educational level
Primary and secondary school	42/192	21.9% (16.2% – 28.4%)	0.2959
University and Master’s/PHD degree	90/342	26.3% (21.7% – 31.3%)	0.2959
Work status
Full-time/part-time job and pensioner	103/390	26.4% (22.1% –31.1%)	0.1916
Student	22/119	18.5% (12.0% –22.6%)
Unemployed	7/25	28.0% (12.1% – 49.4%)
Self-reported sexual orientation
Heterosexual	56/243	23.0% (18.0% –28.9%)	0.4223
LGBTQ+	76/291	26.1% (21.2% – 31.6%)	0.4223
Sexually transmitted infections
- Syphilis
Yes	31/85	36.5% (26.3% –47.6%)	0.0088
No	101/449	22.5% (18.7% – 26.6%)	0.0088
- HIV
Yes	6/16	37.5% (15.2% – 64.6%)	0.2428
No	126/518	24.3% (20.7% – 28.3%)	0.2428
- Hepatitis C
Yes	1/7	14.3% (3.6% – 57.9%)	1.0000
No	131/527	24.9% (21.22% – 28.8%)	1.0000
- Hepatitis B
Yes	1/6	16.7% (4.2% – 64.12%)	1.0000
No	131/528	24.8% (21.2% – 28.7%)	1.0000
- Genital warts
Yes	11/49	22.4% (11.8% – 36.6%)	0.8621
No	121/485	24.9% (21.2% –29.1%)	0.8621
- Molluscum contagiosum
Yes	4/15	26.7% (7.8% – 55.1%)	0.7701
No	128/519	24.7% (21.0% –28.6%)	0.7701
- Gonorrhea
Yes	35/98	35.7% (26.3% – 46.0%)	0.0066
No	97/436	22.2% (18.4% – 26.5%)	0.0066
- Chlamydia
Yes	30/80	37.5% (26.9% – 49.0%)	0.0071
No	102/454	22.5% (18.7% – 26.6%)	0.0071
HIV test
Never/more than 12 months	52/260	20% (15.3% – 25.4%)	0.0159
Less than 12 months	80/274	29.2.% (23.9% – 35%)	0.0159
Has used postexposure prophylaxis (PEP)
Never	12/22	54.5%. (19.8% – 27.4%)	0.0021
At least one time	120/512	23.44% (32.2% – 75.6%)	0.0021
Has used pre-exposure prophylaxis (PrEP)
Never	126/522	24.1% (20.5% – 28.1%)	0.0815
At least one time in the last year	6/12	50.0% (21.1% – 78.9%)	0.0815
Number of sexual partners
Less than 5	50/301	16.6% (12.6% – 21.3%)	<.0001
Equal or more than 5	82/233	35.2% (29.1% – 41.7%)	<.0001
Dating app usage
Almost never/Never	43/236	18.2% (13.5% – 23.6%)	0.0059
Sometimes	25/92	27.2% (18.4% – 37.5%)
Alm–ost always/Always	64/206	31.1% (24.8% –37.9%)
Condom uses with stable partner
Almost never/Never	67/218	30.7% (24.7% – 37.3%)	0.0310
Sometimes	14/72	19.4% (11.1% –30.5%)
Almost always/Always	51/244	20.9% (16.0% –26.6%)
Condom uses with occasional partner
Almost never/Never	29/65	44.6% (32.3% – 57.5%)	0.0006
Sometimes	18/72	25.0% (15.5% –36.7%)
Almost always/Always	85/397	21.4% (17.5% –25.8%)

Moreover, the percentage of sexualised drug users was significantly higher in those diagnosed with Syphilis (36.0% vs 22.0%; p = 0.0088), Gonorrhoea (35.7% vs 22.2%; p = 0.0066) and Chlamydia (37.5% vs 22.5%; p = 0.0071) than in the group of patients without infection. In contrast, no statistically significant association was found between the prevalence of sexualised drug users and the following variables: gender, sexual preference, level of education, occupation, and other infections as Poxvirus and/or Papillomavirus. HIV status and Hepatitis B and C were excluded from analysis due to the low number of cases in the sample.

When comparing characteristics of male versus female users (Table 2), a significant difference (p = 0.0028) was demonstrated regarding the reason for having chemsex. In particular, low self-esteem (24% of females vs 5.6% of males) and pleasure pursuit (52% of females vs 40% of males) prevail in the female group, whereas males are driven by the desire to increase arousal (24.3% of males vs 12% of females) and improve performance (20.6% of males vs 0% of females).. Finally, we found a difference between males and females concerning the intention to stop performing chemsex (p = 0.0203): in particular, 12% of females versus 34% of males expressed the desire to quit it, whereas 72% of females compared to 42% of males were doubtful to end chemsex habits. On the other hand, we did not register any significant differences between genders with respect to the type and frequency of sexualised drugs used, place and/or manner of meeting partners.

Table 2.

Details regarding use of sexualized drugs and chemsex in relation to gender in the last 12 months.

Variables	Female (n = 25)	Male (n = 107)	p-value
Number of times having had chemsex
At least 1 time	28.0% (7)	25.2% (27)	0.7296
Less than 10 times	56.0% (14)	62.6% (67)
More than 10 times	16.0% (4)	12.1% (13)
Drug used
- Methamphetamine
Yes	0.0% (0)	10.3% (11)	0.1235
No	100.0% (25)	89.7% (96)	0.1235
- GHB/GBL
Yes	4.0% (1)	13.1% (14)	0. 3011
No	96.0% (24)	86.9% (93)	0. 3011
- Mephedrone
Yes	0.0% (0)	12.1% (13)	0.1274
No	100% (25)	87.9% (94)	0.1274
- Cocaine
Yes	24.0% (6)	35.5% (38)	0.3489
No	76.0% (19)	64.5% (69)	0.3489
- Ketamine
Yes	8.0% (2)	10.3% (11)	1.0000
No	92.0% (23)	89.7% (96)	1.0000
- Cannabis
Yes	64.0% (16)	31.8% (34)
No	36.0% (9)	68.2% (73)
- Popper
Yes	0.0% (0)	13.1% (14)	0.0709
No	100.0% (25)	86.9% (93)	0.0709
- Sildenafil
Yes	0.0% (0)	6.5% (7)	0.3460
No	100.0% (25)	93.5% (100)	0.3460
- Others
Yes	4.0% (1)	5.6% (6)	1.0000
No	96.0% (24)	94.4% (101)	1.0000
Use of injected drugs
- yes	0.0% (0)	0.9% (1)	1.0000
- No	100.0% (25)	99.1% (106)	1.0000
Use of combined drug
- one drug	91.7% (23)	74.8% (78)	0.1014
- more than one drug	8.3% (2)	25.2% (29)	0.1014
Reason of having chemsex
Enhance performance	0.0% (0)	20.6% (22)	0.0028
Increasing pleasure	52.0% (13)	40.2% (43)
Increasing arousal	12.0% (3)	24.3% (26)
Pressure from partner	12.0% (3)	9.3% (10)
Low self-esteem	24.0% (6)	5.6% (6)
Number of reasons of having chemsex
- one reason	- One reason	77.6% (83)	0.5938
- more than one reason	- More than one reason	22.4% (24)	0.5938
Where chemsex partners were found
Sauna/Dark room/sex club	0.0% (0)	4.7% (5)	0.5829
Dating app	36.0% (9)	61.7% (66)	0.0251
Acquaintance	68.0% (17)	43.0% (46)	0.0278
- one modality	96.0% (24)	91.5% (97)	0.6863
- more than one modality	4.0% (1)	8.5% (10)	0.6863
Place of chsemsex
Sauna/Dark room/sex club	0.0% (0)	7.5% (8)	0.3515
Private Home	84.0% (21)	71.0% (76)	0.2180
Hotel	20.0% (5)	16.8% (18)	0.7705
Private sex parties	12.0% (3)	23.4% (25)	0.2821
- one place	84.0% (21)	84.1% (92)	1.0000
- more than one place	16.0% (4)	15.9% (15)	1.0000
Hospitalization requirement
No	100.0% (25)	97.2% (104)	1.0000
Yes	0.0% (0)	2.8% (3)	1.0000
Condom use during chemsex
Almost never/Never	32.0% (8)	36.4% (39)	0.7253
Sometimes	12.0% (3)	17.8% (19)
Almost always/Always	56.0% (14)	45.8% (49)
Desire of interruption
Yes	12.0% (3)	34.6% (37)	0.0203
No	16.0% (4)	23.4% (25)
Don’t know	72.0% (18)	42.1% (45)

Discussion

Altogether 24.7% individuals in our sample reported having used sexualised drugs in the previous year, with higher prevalence, although not statistically significant, in men compared to women and a slight difference between the proportion of LGBQT+ versus heterosexuals. Interestingly, our data on prevalence exceed most of the results from similar studies. Åse Haugstvedt et al. detected 14% of chemsex practitioners on a sample of 1000 male patients attending the Olafia Clinic in Oslo.¹¹ A larger survey study, conducted in 13 different European cities, attested a prevalence between 0%–14%.¹² Finally, in a systematic review of literature, the overall prevalence for chemsex ranged from 3% to 29%.¹³ Despite data on prevalence variation across different countries and papers, this data shows how sexualised drug usage and chemsex are widespread practices among patients attending our STI centre in Milan, which is the leading centre in terms of attendance and number of services in the city.

In our study people who experienced chemsex or sexualised drugs had higher risk sexual behaviours as demonstrated by the statistically significant association with higher numbers of partners, low condom use, dating app usage and PEP. Predictably these variables are present simultaneously. In 2016, Yeo et al. found that the use of dating apps was associated with multiple sex partners, condomless anal sex and group sex among MSM in Hong Kong.¹⁴ Chemsex was documented as a new category present in dating apps^15,9 and its users vary from others in terms of poor condom utilization.¹⁶ Finally, Maxwell et al found a higher prevalence of chemsex users in the group of patients recruited from dating apps compared with patients recruited from health clinics.¹³Analyses included a significant association between chemsex and STIs. Specifically, we reported a higher percentage of chemsex users in those who had diagnosis of syphilis, gonorrhoea, and chlamydia compared to patients without above mentioned infections. Our analysis expands the evidence derived from multiple surveys^3,17 which reported that engagement in chemsex has been associated with an increased odds ratio of being diagnosed ith acute bacterial STI. In contrast, our data revealed a small number of people living with HIV. Possible explanations for these results might be the short study period and the habit of HIV patients to attend the infectious disease outpatient service rather than the STI centre of our hospital. Finally, no difference among the two groups were found in terms of viral infections, such as Poxvirus and/or Papillomavirus.

Sociodemographic data including mean age, occupation and level of education are homogeneous among the two groups. Attending patients are mostly in their 30s, highly educated and fully or partially employed. On one hand these findings are in line with previous research^11,18 and reflect the definition Stuart¹⁹ gave to chemsex identifying it as a specific form of recreational drug use. It is now well known that sexualised drug usage and chemsex are mainly an adult phenomenon which differs from recreational and party drugs which are more common phenomena among teenagers.²⁰ On the other hand, the above-mentioned characteristics are commonly found in patients attending our STI centre.

Furthermore, we decided to investigate the phenomenon with respect to gender. While comparing the two groups, differences were found only in two categories: motivations that led to practise chemsex and desire to stop. Data showed similar results for all other variables. Moreover, in our work neither self-sexual orientation nor gender revealed a significat statistical association with chemsex. We believe that it is a matter of interest since most studies are limited to MSM or HIV+ status patients^1,2,4,5,7,11

Finally, during the questionnaire compilation patients had the possibility to report, in addition to the classical “Chems” (Methamphetamine, GHB/GBL, Mephedrone), various drugs which were used during the sex act to heighten their experience: almost 40% of sexualised drug users reported cannabis inhalation, often mixed with multiple substances. Our results should be interpreted considering several limitations. First, patients included were from only one venereological outpatient clinic in Milan; results are therefore not directly transferable to the general population. Second, the study was partially conducted during the period corresponding to the Italian lockdown caused by the COVID-19 outbreak: some data may be affected by this circumstance. For example, in our survey, private homes were the most frequent place chosen by the subjects to perform chemsex. Finally, some groups have a small sample size (e.g., people with HIV, HCV and HBV).

The strength of our study is the inclusivity of the sample (LGBQT+, heterosexuals, male and female patients). Moreover, to the authors knowledge, this is the largest survey on chemsex conducted in Italy.

In conclusion, the importance of this research lies in having demonstrated that in Milan sexualised drug usage and chemsex are frequently practiced, regardless of genders and sexual orientations. This survey identified a specific population with higher-risk sexual behaviours and incidence of acute bacterial STI. Healthcare professionals need to be aware of this practice and its related risks. Results should drive the development of appropriate and adapted interventions to promote prevention and effective measures.

Footnotes

Author’s contribution

Study conception and design: S.G, S.R and M.C. Acquisition of data: F.B, SR and S.G. Analysis and interpretation of data: M.C, G.C and S.G. Drafting of manuscript: S.G. Critical revision: G.C, M.C and A.V.M. All authors have read and agreed to the published version of the manuscript.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Serena Giacalone

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