Effect of education on overall and cause-specific mortality in injecting drug users, according to HIV and introduction of HAART.Int J Epidemiol. 2007 Feb; 36(1):187-94.IJ
We assessed the impact of education on long-term overall and cause-specific mortality among 6575 injecting drug users (IDUs) according to HIV status and introduction of highly active antiretroviral therapy (HAART).
Community-based cohort study of IDUs recruited in three AIDS prevention centres (1987-1996). Causes of death were ascertained in clinical centres and Mortality Registry and classified as AIDS, drug use related, injuries, or liver diseases. Poisson regression models including education and calendar period interaction and adjusted by sex, age, and HIV were used.
In 73 901 person-years of follow-up, there were 1493 deaths (20.2/1000 person-years): 761 related to AIDS, 234 to drug use, 179 to injuries, and 93 to liver diseases. IDUs with university studies had a lower risk of death (RR 0.52; 95% CI 0.36-0.77) than those without studies: this difference was higher after (RR 0.45; 95% CI 0.25-0.80) than before 1997 (RR 0.68; 95% CI 0.41-1.13). Compared to before 1997, while decreases in the risk of AIDS mortality were seen during 1997-2004 for both lower (RR 0.49; 95% CI 0.41-0.58) and higher (RR 0.33; 95% CI 0.23-0.48) educated, only those higher educated experienced a reduction in drug-use mortality (RR 0.54; 95% CI 0.28-1.05) and death from injuries (RR 0.52; 95% CI 0.23-1.21).
Independently of HIV status, lower education predicts a higher risk of death in IDUs and its impact is stronger after 1997. Education has a protective effect on most causes of death and it cannot be entirely attributable to the access or use of HAART.