RESUMEN
BACKGROUND: Except for injecting drug use, other routes of transmission for hepatitis C virus among HIV-AIDS patients have not been consistently described, and risk estimates are often not adjusted for confounding factors. AIMS: To evaluate characteristics associated with hepatitis C virus infection in individuals infected with the HIV. PATIENTS: Cases were patients co-infected by HIV and hepatitis C virus, and controls were infected only by HIV. METHODS: Cases and controls were consecutively enrolled at a public health care outpatient HIV-AIDS reference centre in Porto Alegre, Southern Brazil. RESULTS: A total of 227 cases (63% men; 40.3+/-8.7 years) and 370 controls (44.6% men; 38.9+/-9.8 years) were enrolled in the study. In a multiple logistic regression model, male gender (odds ratio 1.9; 95% confidence interval 1.3-2.7), age between 30 and 49 years (odds ratio 2.1; 95% confidence interval 1.2-3.7), elementary school education (odds ratio 4.2; 95% confidence interval 1.9-9.6), lower family income (odds ratio 1.7; 95% confidence interval 1.1-2.7), sharing personal hygiene objects (odds ratio 2.0; 95% confidence interval 1.3-3.3), using injected drugs (odds ratio 21.6; 95% confidence interval 10.8-43.0) and crack cocaine (odds ratio 2.8; 95% confidence interval 1.1-6.9) were independently associated with co-infection by hepatitis C virus. CONCLUSION: These results confirm the risk profile for hepatitis C virus-HIV infection and suggest that sharing personal hygiene objects might explain the transmission of virus C to those not infected by the usual routes, which may be of relevance for developing preventive strategies.