The determinants of methadone maintenance treatment in opioids dependence users: A survival analysis study.

Background: Staying in treatment is one of the basic principles in maintenance treatment with methadone and it is considered as a success criterion in the treatment procedure. This study aimed at analyzing effective determinants on staying in treatment in methadone treatment procedure. Methods: This was a retrospective cohort study, in which 6 MMT centers were randomly selected to be studied. The data were collected using the patients' medical records. Therefore, 1008 medical record files belonging to the patients who received methadone treatment from April 2013 to August 2017 were investigated. Proportional hazard Cox regression (extended) was used to specify the determinants of the methadone maintenance treatment and STATA 11 was used for data analysis. Results: The patients' mean age was 38.8 years (±1.08), and 75.8% were married and only 39.1% had full-time jobs. The mean age for the first substance abuse was at 24.31years (±7.93). The average time of staying in the treatment was 28.8 months. The results of the adjusted Cox proportional hazards regression showed among the 14 variables entered into the model, in the 1-12-month interval age of first drug use (HR=0.945, 95 % CI=0.908-0.983, p=0.005), specific drug use (HR=1.14, 95 % CI=1.026-1.268, p=0.014), and the frequency of treatment (HR=0.974, 95 % CI=0.959-0.990, p=0.002) were significantly correlated with survival status. The 13-36- month interval drug use (HR=0.931, 95 % CI=0.886-0.978, p=0.005) was significantly correlated with survival status. Also, the range of 37-53 month drug use (HR=1.058, 95 % CI=1.001-1.119, p= .044) had a significant relationship with survival status. Conclusion: This study showed age of first drug use, specific drug use, the frequency of treatment and drug use were correlated with a decrease in staying duration in treatment. Therefore, taking these factors into consideration in designing and administering various interventions in addiction treatment and consulting centers is of paramount importance.