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.