Monitoring consumption of methadone and heroin in major Chinese cities by wastewater-based epidemiology.

BACKGROUND: Methadone maintenance treatment (MMT) services have been used in China for treatment of heroin dependence. But no study has been conducted to assess the appropriateness of MMT distribution and the potential abuse of methadone in China. This study aims to do that through a nationwide estimation of methadone consumption in China via wastewater-based epidemiology and subsequently compare it with MMT data and level of heroin abuse. METHODS: Wastewater samples were collected from 53 wastewater treatment plants in 27 major cities that cover all geographic regions of China. Methadone and pure heroin consumptions were estimated based on influent concentrations of methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), morphine and codeine. RESULTS: Drug residues were detected in most samples. The ratio of EDDP/methadone was around 2 in influents and methadone and EDDP loads were strongly correlated, indicating that they originated from human consumption. Both influent methadone and EDDP loads in Southwest and Northwest China were significantly higher than those in other regions. The highest estimated consumptions of methadone and heroin in China were 22.0 ±â€¯2.1 mg/1000 in./d and 263.9 ±â€¯115.9 mg/1000 in./d, respectively. There was a significant positive correlation between methadone and heroin consumptions. CONCLUSIONS: Consumption of methadone in China was primarily from MMT services. The use of methadone and heroin displayed a clear geographical pattern: it is higher in the western inland regions than in the eastern regions. This study has shown that the distribution of MMT services is reflective of the level of heroin abuse in different regions of China.

[Risk factors which were associated with heroin use during the methadone maintenance treatment among 1301 patients in 9 cities of China.].

OBJECTIVE: To determine the proportion of heroin use among patients who were involved in community-based methadone maintenance treatment (MMT) program and to identify the risk factors associated with heroin use. METHODS: This study was conducted in 9 MMT clinics within 3 provinces. Thirteen hundred and one patients who met the study criteria were selected from each of the five groups with different dosages of methadone users. An administrative questionnaire was applied to explore the demographics, drug abuse-related behaviors and MMT services received by the clients, etc. The prevalence of depression and anxiety among the clients were also collected by SAS and SDS. Urine samples were collected as a biological marker to indicate if heroin had been used. RESULTS: Of the 1301 patients, 76.2% were males. The mean age was (34.6 +/- 6.5) years while 71.7% had an education level of primary school or below. The average daily dosage of methadone was (48.1 +/- 29.4) mg and self-satisfied evaluation score on treatment was 8.6. On average, 27.7% urine samples showed positive opiate evidence. Marital status, employment status, treatment retention, self-satisfied evaluation score on dosage and dropout history were found to be significantly associated with heroin use, while gender, education level and dosage had no significant association with heroin use. It seemed that risk factors that associated with heroin use were different from areas to areas. CONCLUSION: High quality MMT clinic services, high self-satisfied score, longer treatment retention and low dropout rate seemed to have the effects of reducing the risk of ongoing heroin abuse under the methadone maintenance treatment program.