LAUSR

Objective: To estimate the incidence of drop out of treatment in patients with access to methadone maintenance treatment and explore the correlation and interaction between insufficient methadone dosage and morphine positive urine on the drop out in Guangxi Zhuang Autonomous Region. Methods: Face to face interview was conducted in 1 031 patients at 3 methadone maintenance treatment clinics in Guangxi. Results: The study included 1 031 participants, 40.6% of them (419/1 031) had stopped treatment. The drop out rates in urine morphine positive group and methadone dosage<100 mg/d group were 57.6% (99/172) and 37.4% (347/929) respectively, higher than those in urine morphine negative group and methadone dosage ≥100 mg/d group (42.3%, 363/859, and 26.5%, 27/102). Orderly logistic regression analysis results showed that after adjusted factors, such as gender, age, marital status, ethnic group, patients who received a dosage less than 100 mg/day (OR=3.05, 95%CI: 1.84-5.06) and had morphine positive urine (OR=2.25, 95%CI: 1.59-3.19) were more likely to drop out of the treatment. Interaction analysis showed that dosage less than 100 mg/d and morphine positive urine during treatment had additive interaction (RERI=256.46, AP=0.87, S= 8.05) and multiplication interaction (OR=2.45, 95%CI: 1.71-3.49). Conclusion: Insufficient dosage and morphine positive urine were significantly correlated with drop out of treatment in patients with access to methadone maintenance treatment.