Introduction Crack users are at high risk for syphilis, due to multiple risk behaviours, such as inconsistent condom use, exchanging sex for money and/or drugs and multiple sexual partners. However, there is a gap in the literature on the epidemiology of this infection in crack users in developing countries, including Brazil. The aim of this study was to investigate the prevalence and risk factors of syphilis in crack users in Goiânia, Brazil Central.

Methods A cross-sectional study was conducted with 600 users of a reference unit for chemical dependency treatment of Goiás, between 2012 to 2013. All participants were interviewed regarding socio-demographic characteristics and risk behaviours and blood samples were then collected for the detection of anti-Treponema pallidum antibodies using enzyme-linked immunosorbent assay (ELISA). Positive samples were tested by the Venereal Disease Research Laboratory (VDRL). Active syphilis was considered when there was a positive ELISA result and VDRL titers≥1:8. Poisson regression analysis was used to analyse the factors associated with active syphilis.

Results Of the total participants, 13.8% (95.0% CI: 11.3% to 16.8%) were positive in ELISA. The prevalence of active syphilis was 4.5% (95.0% CI: 3.1% to 6.5%). The prevalence of exposure to Treponema pallidum and active syphilis was statistically higher in women than in men (p<0.001). In multivariable model, female sex (adjusted prevalence ratio [APR]: 3.73; p<0.001), schooling (APR: 0.88; p=0.030), exchange sex for money and/or drugs (APR: 3.22; p=0.040) and a history of genital ulcers in previous six months (APR: 4.12; p=0.010) were associated with active syphilis.

Conclusion The results of this research show high prevalence of syphilis in crack users in Goiânia city. Comprehensive care for this population should be offered, including strategies such as health education, condom provision, and regular infection testing.

Support: Fundação de Amparo a Pesquisa do Estado de Goiás – FAPEG; Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq