Em um estudo transversal com uma amostra de 420 usuários de drogas de Porto Alegre, Rio Grande do Sul, Brasil, foram avaliados demografia, uso de drogas e situações de risco para contaminação pelo HIV por meio da versão brasileira do questionário Comportamentos de Risco para AIDS. A prevalência de HIV positivos foi de 22,6%; 39,3% tinham 30 anos ou mais e 69,5% eram homens. Nos trinta dias prévios à coleta, 56,8% tinham usado maconha, 43,6% cocaína inalada, 17,6% cocaína injetada e 42,4% álcool freqüentemente. As variáveis que se mantiveram associadas com infecção por HIV após regressão logística foram idade superior a trinta anos (RC: 2,89; IC95%: 1,17-7,12), ter menos de sete anos de estudo (RC: 2,10; IC95%: 1,02-4,36), renda de menos de um salário mínimo (RC: 2,89; IC95%: 1,32-6,32) e ter usado droga injetável (DI) (RC: 5,18; IC95%: 2,89-9,28). A taxa de infecção pelo HIV encontrada foi alta, considerando que 70,0% nunca haviam usado DI. As variáveis associadas com contaminação por HIV estão de acordo com as literaturas nacional e internacional e com o modelo teórico de exposição a risco proposto pelo primeiro autor.

A cross-sectional study with a sample of 420 drug users from Porto Alegre, Rio Grande do Sul State, Brazil, was utilized to assess demographic variables, drug use, and risk behaviors for HIV infection. We used the Brazilian version of the Risk Assessment Battery. Overall HIV seropositivity was 22.6%; 39.3% of the subjects infected were at least 30 years old, and 69.5% were males. In the month prior to the interview, 56.8% of the sample had used marijuana, 43.6% had sniffed cocaine, 17.6% had injected cocaine, and 42.4% had used alcohol on a frequent basis. The variables that continued to be associated with HIV infection after logistic regression were age (30 or older) (OR: 2.89; 95%CI: 1.17-7.12), having less than seven years of schooling (OR: 2.10; 95%CI: 1.02-4.36), having a monthly family income of less than one minimum wage, or approximately U$90 (OR: 2.89; 95%CI: 1.32-6.32), and having injected drugs (OR: 5.18; 95%CI: 1.32-6.32). Seroprevalence in this sample is considered high, particularly since 70.0% of the sample reported no prior drug injection. Variables associated with HIV infection are similar to the national and international literature and agree with the theoretical model of risk behavior proposed by the first author.