Survival study of opioid addicts in relation to its adherence to methadone maintenance treatment.

Abstract Objectives: To study the putative role of methadone maintenance treatment in the improvement of life expectancy of opioid addicts. Design: Retrospective longitudinal study . Participants: All 1487 patients receiving methadone maintenance treatment in Alicante between June 1990 and December 1997. Statistical analysis: Mortality rates were studied using Kaplan–Meier survival curves. Protection or risk factors were analyzed using Cox's proportional hazards model. Results: Mortality rates decreased from 87/1000 in 1991 to 17/1000 in 1997. The following factors influenced mortality: HIV infection [Hazard Ratio (HR)=7, 95% confidence interval (CI)=4–12]; current methadone status (HR=3.2, 95%CI=1.5–7.1) and MMT retention (retained vs. drop-out, HR=0.5, 95%CI=0.2–1.1; re-enrolled vs. drop-out, HR=0.3, 95%CI=0.2–0.5). Conclusion: Expediting entry and re-enrolling in methadone maintenance treatment improves survival.