Chemsex practice among men who have sex with men (MSM) during social isolation from COVID-19: multicentric online survey.

The aim of this study was to investigate factors associated with sex practice under the effect of drugs (chemsex) among men who have sex with men (MSM) during the period of social isolation in the context of the COVID-19 pandemic. A multicenter online survey was applied to Brazil and Portugal in April 2020 when the two countries were under restrictive health measures due to the pandemic. Participants were recruited with an adaptation of the respondent driven sampling (RDS) method in the online environment. Data were collected using social networks and dating apps for MSM. We used bivariate and multivariate logistic regression to produce crude (OR) and adjusted odds ratios (aOR). In a universe of 2,361 subjects, 920 (38.9%) reported engaging in chemsex practice, which involved casual partners in 95% of the cases. Higher OR of engaging in chemsex were associated with Brazil (aOR = 15.4; 95%CI: 10.7-22.1), not being in social isolation (aOR = 4.9; 95%CI: 2.2-10.9), engaging in casual sex during social distancing (aOR = 52.4; 95%CI: 33.8-81.4), group sex (aOR = 2.9; 95%CI: 2.0-4.4), not presenting any symptom of COVID-19 (aOR = 1.3; 95%CI: 1.1-1.8), not living with the sex partner (aOR = 1.8; 95%CI: 1.2-2.6), and using pre-exposure prophylaxis (aOR = 2.6; 95%CI: 1.8-3.7). The occurrence of chemsex was high, especially in Brazil, where the proposed social distancing did not gain adherence by MSM.