ChemsexPH: The association between chemsex, HIV status and adherence to antiretroviral therapy among men who have sex with men in the Philippines

Abstract Introduction Chemsex, the use of psychotropic drugs before or during sexual intercourse, is associated with various HIV risk factors, including condomless sex and reduced adherence to pre‐exposure prophylaxis or antiretroviral therapy (ART). In the Philippines, there are still limited studies exploring the associations between chemsex, HIV status and ART adherence. This study aims to compare recent and lifetime chemsex engagement in association with self‐reported HIV status among Filipino men who have sex with men (MSM). We further explored the association between chemsex and ART adherence among people living with HIV engaged in chemsex. Methods A cross‐sectional online survey of 479 Filipino MSM was conducted from 3 August to 1 December 2019. Demographic profiles, sexual behaviours, drug use, history of sexually transmitted infections (STIs), chemsex engagement and HIV status were collected and analysed. Bivariable and multivariable logistic regression were employed to assess the association between self‐reported HIV status and chemsex engagement. Results Among the 479 respondents, Filipino MSM engaged in drug use and chemsex were generally older compared to those not engaged in drug use and chemsex (average age 31−33 vs. 29 years old; p<0.05). Methamphetamine was the most common drug for people who reported using drugs. An HIV‐positive status was associated with recent chemsex engagement (aOR = 5.18, p<0.05) and a history of STIs (aOR = 2.09, p<0.05). The subgroup analysis showed that 79% (166/200) of persons living with HIV were adherent to ART. There was no significant association found between chemsex and ART adherence in the logistic regression analyses. Conclusions Chemsex behaviour, particularly recent chemsex engagement, is significantly associated with self‐reported HIV status. The emerging data on MSM engaged in chemsex require integration of a more person‐centred, comprehensive and robust harm reduction programmes into the existing combination prevention strategies in the country. Health education for Filipino MSM engaged in chemsex should prioritize raising awareness about methamphetamine effects and overdose risks, alongside proper medical management.


I N T R O D U C T I O N
The Philippines had a 237% increase in new HIV cases between 2010 and 2018, making it one of the countries with the highest HIV incidence in Southeast Asia [1,2].The majority of reported HIV cases in the Philippines are among men who have sex with men (MSM), with only 3% linked to people sharing non-sterile needles [3].Consequently, the HIV prevention efforts have been focused heavily on male-to-male sexual transmission risk.However, limited harm reduction programmes exist for Filipino people who inject drugs (PWID), especially for MSM engaged in chemsex-an emerging phenomenon in the Philippines.
Dearth in Philippine-based chemsex-related research remains despite global evidence linking chemsex to HIV incidence among MSM [5,26,27].A comprehensive review in Asia-Pacific in 2010−2021 did not identify any recent Philippine-based chemsex study [28].Hence, this study aims to address this gap by comparing recent and historical chemsex engagement among Filipino MSM and determine its association with self-reported HIV status.Additionally, a subgroup analysis was conducted to assess the association of chemsex engagement with ART adherence among Filipino PLHIV.This study underscores the necessity for countryspecific data in the Philippines to inform tailored prevention and harm reduction approaches, cautioning against solely relying on findings from other countries.

M E T H O D S
An anonymous cross-sectional online survey was conducted between 3 August and 1 December 2019, using voluntary response sampling posted on social media (i.e.Facebook, Twitter/X), consisting of four main parts: informed consent (placed at the first part of the online survey where the nature and purpose of the study were explained and ensuring confidentiality) and inclusion criteria screening, demographic profile, sexual health status including STI and HIV information, and drug use and chemsex experiences.Then, respondents were screened based on the following inclusion criteria: (1) Filipino citizen living in the Philippines at least within the last 6 months at the time of data gathering; (2) 18 years old and above; and (3) identifies as cisgender man having sex with men.The survey was voluntary and non-incentivized, with the approval of the Philippine Health Research Ethics Board (20190715-108-NEC).

Self-reported HIV status
The dependent variable in this study was self-reported HIV status.Respondents were asked to report their HIV status based on their most recent HIV testing.The responses were categorized into three groups: HIV positive, HIV negative and unknown status.

ART adherence
For respondents who reported an HIV-positive status, a visual analogue scale (VAS) was used to ask their adherence to ART, representing 0−100% adherence.Categories were either "adherent" (≥90%) or "non-adherent" (<90%).The cutoff for adherence was set at 90% based on the previous study [29].

Chemsex engagement
The

Demographic profile
This included measures such as age in years, location in the Philippines (categorized as Metro Manila/Luzon or the rest of the Philippines), education level (high school or lower vs. college or higher) and employment status.Location is a covariate because residing in major cities like Manila and Luzon is associated with higher accessibility to illicit drugs and HIV care facilities.

Access to ART, and access to pre-exposure prophylaxis
This measured access to antiretroviral medications after they responded to the HIV status question wherein HIV-negative respondents were directed to questions on access to preexposure prophylaxis (PrEP), while respondents who reported and HIV-positive status were directed to questions on access to ART.

Condomless anal sex
This measured the occurrence of penetrative anal or vaginal sex without using a condom, categorized as "≤6 months ago" or ">6 months or never."

History of STIs
Respondents were asked "Have you ever been diagnosed with any STIs other than HIV in the past?" with responses categorized as "Yes," "No" or "Unknown."Those who answered "Yes" were directed to select a specific number of STIs they had in the past: one versus two or more.

Characteristics of drug use
Only respondents who answered as DU, CDU or CDU6 were directed to the following questions: "What is your primary drug of choice?" (single selection from a list of specific drugs, with an option to specify "others"), "Have you used two or more drugs at the same time?"for engagement in polydrug use; "Have you ever shared needles while injecting drugs?"; and "Age of first drug use" (answered with "before 18 years old" or "at 18 years old or older").

Age of first penetrative sex
This variable captured the age of first engagement in vaginal or anal penetrative sex and was categorized "before 18 years old" or "at 18 years old or older."

A N A LY S I S
Data analysis in this study was conducted using IBM SPSS Statistics version 25 (IBM Corp., 2017).Descriptive statistics summarized population characteristics, while inferential statistics employed univariable and multivariable logistic regression utilizing purposeful covariate selection method [30]; significant covariates at p<0.05 level in the univariable logistic regression model were included in the final multivariable model.The subgroup analysis of association between ART adherence and chemsex among PLHIV used similar covariate selection criteria as the main regression analysis.Variance inflation factor tests were done to ensure no multicollinearity.

R E S U LT S
Out of 716 survey responses initially received, 237 were excluded due to duplication (8.4%), inconsistent information (16%), non-residency in the Philippines during data collection (6.8%) or not identifying as MSM (68.8%).The final data analysis involved 479 Filipino MSM (response rate = 66.9%).

General characteristics of the respondents
The age of respondents ranged from 18 to 56 years old (Median = 30; IQR = 24−34).Nearly half (47.0%) of the respondents were from Metro Manila and Luzon Regions, and 64.7% held a college degree or higher education.Moreover, 74.1% of the respondents were employed.Over half (65.1%) reported having their first penetrative sex at 18 years old or older, while 34.9% had their first penetrative sexual experience before the age of 18 (Table 1).Among 479 respondents, 74.1% reported never using drugs nor engaged in chemsex (non-C/DU), 7.3% reported drug use but not for chemsex (DU), 10.2% had engaged in chemsex, but not recently (CDU) and 8.4% engaged in chemsex within the last 6 months (CDU6).Approximately 6.1% of Filipino MSM reported having first used drugs before the age of 18, while 19.8% began using drugs at 18 years old or older.Regarding self-reported HIV status, about 47.6% were HIV negative, 43.8% were HIV positive and 8.6% reported an unknown HIV status.
There were 95.2% (200/210) reported having access to ART among respondents reporting an HIV-positive status, while 93.9% (214/228) reported to have no access to PrEP among those reporting HIV-negative results.

Characteristics of drug use among Filipino MSM engaged in chemsex
Among the 124 who reported using drugs and engaging in chemsex, the most common drugs used were methamphetamine (19.4%) and nalbuphine/Nubain (8.9%).There were 23.4% who reported polydrug use, and 12.9% engaged in needle sharing during injection.

Subgroup analysis: association between chemsex and ART adherence among PLHIV
Among respondents who reported HIV-positive status and had access to ART, there were 83% (166/200) who were adherent to ART (Table 3).Among the four groups, the highest proportion of ART adherence were among non-C/DU group (85.3%), while the highest proportion of ART non-adherence were among the CDU6 group (29.6%).Both univariable and multivariable logistic regression analyses revealed no significant association between ART adherence and chemsex.Notably, both univariable and multivariable regression analyses showed that recent CAS within the last 6 months was negatively associated with ART adherence (OR = 0.27, 95% CI = 0.12−0.64,p = 0.003 and aOR = 0.29, 95% CI = 0.12−0.71,p = 0.007, respectively).

D I S C U S S I O N
This nationwide survey conducted in the Philippines assessed chemsex as an emerging phenomenon among MSM, with methamphetamine being the primary drug of choice among Filipino MSM, and associated behaviours resonating with previous research [21,24,31].Findings also reveal that 18.6% of Filipino MSM have chemsex engagement, surpassing the 13% regional average in East and South Asia [21].Moreover, the unique approach of comparing four groups of Filipino MSM noted that the proportion using drugs in a sexual context rather than recreational.Drug use among Filipino MSM is context-dependent as explored by previous studies [7,23]-potentially as a form of experiential experimentation, coping mechanism, intimate connection, sexual disinhibition or performance enhancement among employees working longer shifts.This requires a combination of prevention strategies a There were 10/210 Filipino PLHIV who reported to have no access to ART and was removed from this regression analysis.b Significant associations at p-value <0.05.
with intensified harm reduction interventions, especially for methamphetamine users.
Recent chemsex is significantly associated with an HIVpositive status even after adjusting for significant covariates, aligning with previous research conducted in Asia [15,28,[31][32][33].Furthermore, the subgroup analysis revealed findings similar to the Manila-based study [24]-the slightly higher proportion of ART non-adherent MSM who were engaged in recent chemsex, and the negative association between recent CAS and ART adherence.These reaffirm the need to strengthen adherence counselling among PLHIV while addressing the underlying motivations for chemsex engagement, assessing sexual behaviour patterns and providing risk reduction strategies.
The high proportion of MSM (93.9%) without access to PrEP highlights the need for efforts towards increasing access.It is worthwhile to note, however, that there were limited PrEP guidelines in the country at the time of data gathering in 2019.The Philippines started the PrEP scaleup in 2020 through the Department of Health's interim guidelines and inclusion of PrEP in the formulary system [37,38].
This research has limitations impacting the interpretation of findings.The cross-sectional design prevents definitive causation between chemsex and HIV transmission.Self-reported data collection methods may have underestimated chemsex engagement, ART adherence and self-reported HIV status, partly due to the sensitive nature of HIV and the highly criminalized nature of drug use in the Philippines.While indicating higher chemsex prevalence among Filipino MSM than in international studies, the lack of direct comparison with national data hinders country-specific assessment.Recruitment through social media may introduce bias by excluding MSM without internet access, affecting generalizability.ART adherence measurement may not be ideal, but using VAS in this community-based survey was more comprehensible for respondents.The lack of timeframe only reflected respondents' current perception towards their adherence.Additionally, lifetime STI history may be less relevant to recent sexual experiences.

C O N C L U S I O N S
This study examined and revealed the nuanced associations between chemsex, HIV status and ART adherence in Filipino MSM.The significant association between ART non-adherence and recent chemsex engagement highlights the necessity for interventions promoting adherence and harm reduction within HIV care.The complex factors influencing ART adherence underscore the need to integrate person-centred and structural interventions to support informed decision-making among Filipino MSM engaged in chemsex.

Table 1 . Cross-tabulation of demographic, sexual and HIV/STI profiles with chemsex engagement among Filipino men who have sex with men (N = 479)
://onlinelibrary.wiley.com/doi/10.1002/jia2.26323/full| https://doi.org/10.1002/jia2.26323 a Level of significance calculated using Kruskal−Wallis test.b Significant p-values <0.05.c Level of significance calculated using chi-square tests.d Level of significance calculated using Fisher's Exact tests.e Access to ART used the denominator corresponding to the total number of self-reported HIV-positive status, while access to PrEP corresponds to the total number of self-reported HIV-negative status.http