Risk factors associated with polydrug use among clients of methadone maintenance treatment clinics in 3 Chinese provinces

Objective To determine the proportion of polydrug use among heroin addicts attending methadone maintenance treatment(MMT) clinics and to identify its associated risk factors.Methods This study was conducted in 6 MMT clinics in 3 provinces,and 1 202 clients who met the study criteria were selected from these clinics.Urine samples were collected as a biological marker to identify if heroin,methamphetamine,ecstasy,benzodiazepine or buprenorphine had been used.Then,a questionnaire was used to collect demographic information and information on polydrug use-related behaviors.Results The average age of the 1 202 clients was 39.7±6.8 years.Among them,75.7% were males,and 62.5% had an education of primary school or below and 56.7% were jobless.The average length of drug use was 15.6±4.8 years.156(12.9%) clients continued to use heroin and 426 clients(35.4%) used other drugs in the last 6 months during MMT.Residence areas,employment status,relationship with family,the average daily methadone dosage,and other drugs use were associated with heroin use(P0.05).Residence areas,employment status,casual sex partners,treatment duration,having other drugs use experience before MMT,high-frequency of heroin use during MMT were found to be significantly associated with other drugs use(P0.05).Conclusion Continued heroin use and other drugs use were common in MMT clinics.Interventions for polydrug use should be strengthened in order to improve the effectiveness of MMT.