Determinants of HIV sero-conversion among male injection drug users enrolled in a needle exchange programme at Karachi, Pakistan

Objective: To assess the determinants of HIV sero-conversion among male injection drug users enrolled in needle exchange programme at Karachi. Methods: An unmatched retrospective case control study was conducted among male injection drug users receiving needle exchange services in Karachi. The cases and controls were identified from one drop in center providing needle exchange services. The data for the study participants was collected retrospectively from the programme. Descriptive statistics, univariat analysis, and multivariate regression analysis for determinants of HIV sero-conversion and Hosmer and Lameshow goodness of fit test for model adequacy were performed. Results: Mean age of the study participants was 34.17 ± 10.74 years. Average monthly income of the participants was US$ 125.15±76.32. In unconditional multivariate regression analysis being unmarried (AOR: 3.0 95% CI 1.14-7.9, p=0.02), not living with family (AOR: 2.8 95% CI 1.18-6.79 p=0.02), family history of addiction (AOR: 2.5, 95% CI 1.01-6.49, p=0.04), injecting drugs in groups (AOR: 2.8, 95% CI 1.12 7.02 p=0.02), not obtaining syringes from the programme (AOR:26.45, 95% CI 2.47-282.8 p=0.007), and history of blood transfusion (AOR: 52.9, 95% CI 1.32-2118.416 p=0.03) were significantly associated with HIV positive sero-status. Model adequacy was assessed by Hosmer and Lameshow goodness of (J: 4.95, p=0.7) indicating that the model was accurate. Conclusion: Social and drug related risky behaviours are important determinants of HIV among male IDUs in Karachi. The situation calls for programmematic initiatives for addressing the risky behaviours among IDUs for effective control of epidemic in the country.