Mortality and HIV transmission among male Vietnamese injection drug users

Abstract

To estimate all-cause mortality rate and to assess predictors of all-cause mortality among injection drug users (IDUs) in Thai Nguyen province, Vietnam between 2005 and 2007. Prospective cohort study. Community-dwelling IDUs were enrolled and followed at 3-month intervals for up to 2 years. A total of 894 male IDUs (median age of 32 years, 22.8% HIV-positive, all having injected opioids). Deaths were confirmed by family members and by reviewing government records. Marginal Cox proportional hazards models for clustered data were constructed to determine the independent predictors of all-cause mortality, using both fixed baseline measurements and time-dependent repeated measurements. During 710.1 person-years of follow-up, 45 (5.0%) drug injectors died. The causes of deaths were AIDS-related (14 cases, 31%), drug overdose (12, 27%), suicide (three, 7%), traffic accident (three, 7%), violence (two, 4%), pneumonia (two, 4%), non-traffic accident (one, 2%) and unknown causes (eight, 18%). The all-cause mortality rate was 6.3% (95% CI = 4.6-8.5) per 100 person-years. The standardized mortality ratio was 13.4. The HIV incidence rate was 5.2 (95% CI = 3.5-7.6) per 100 person-years. In multi-factorial analysis, HIV infection [hazard ratio (HR) = 3.5, 95% CI = 1.9-6.3] and previous diagnosis of tuberculosis (HR = 10.0, 95% CI = 4.1-24.3) were associated significantly with increased hazard of death. The all-cause, age- and sex-standardized mortality among Vietnamese IDUs is 13-fold higher than the general population and substantially higher than IDUs studied in developed countries. Effective prevention and control of HIV infection and tuberculosis are needed urgently.