Article Text


Epidemiology poster session 2: Population: Injection drug users
P1-S2.26 Drug and sexual HIV risk among injection drug users - a latent class analysis
  1. S Noor
  1. University of Texas School of Public Health, Houston, USA


Background Injection drug users (IDUs) are at increased risk of HIV infection because they are more likely to engage in high risk injection behaviours (eg, needle sharing) as well as in high risk sexual behaviours (eg, exchange sex). This analysis examines factors associated with HIV risk using a latent class approach.

Methods Our study includes 523 eligible injection drug users, recruited into the 2009 National HIV Behavioural Surveillance project. Using maximum likelihood we calculated the posterior probability of being in an HIV risk class from nine drug and sexual behaviours. We simultaneously fitted a multinomial regression model to identify socio-demographic factors associated with HIV risk class.

Results We identified 3 HIV risk classes—high (42%), moderate (25%) and low risk (33%). Compared to the high HIV risk class, homeless IDUs had lower odds to be in the moderate (OR=0.16, 95% CI 0.04 to 0.70) and in low risk HIV class (OR=0.28, 95% CI 0.15 to 0.52). Moreover, IDUs who were arrested in the past 12 month had also lower odds to be in low risk class (OR=0.52, 95% CI 0.32 to 0.86) compared to high HIV risk class.

Conclusions Our results show that the majority of our IDUs were engaged in high HIV risk behaviours. Though temporality cannot be established due to the cross-sectional study design our findings indicate that homelessness and history of incarceration are associated with HIV risk. Interventions targeting system-level change may help to reduce the burden of HIV among the injection drug user population.

Statistics from

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.