A large proportion of China’s heroin addicts are incarcerated in compulsory detoxification centers where methadone treatment is unavailable . Once released from these centers, relapse rates are estimated to be greater than 90% [6–9]. The probability of acquiring HIV is considered high in this population, due to high-risk, drug use-related injecting and sexual behaviors, both inside and outside of detoxification centers . Expansion of methadone treatment coverage to include recently-released heroin addicts is critical to harm reduction in this population. However, effective interventions aimed at improving referral to community-based MMT clinics for newly-released prisoners in China are lacking.
This study evaluated the effectiveness of three referral models at successfully transitioning heroin users from compulsory detoxification to MMT participation. Findings show that use of a referral model that incorporates methadone treatment for heroin addicts while they are still incarcerated increases the probability of their enrollment and participation in MMT after their release. Adjusted analyses indicate that prior experience with methadone is the only study variable associated with increased odds of successful MMT referral. These results have important implications for both heroin addiction treatment and HIV transmission prevention in China, as they suggest that treating incarcerated heroin users with methadone prior to their release may promote their subsequent enrollment and participation in MMT. Additional research among heroin users from different regions in China is needed to further confirm the effectiveness of this referral card plus MMT intervention in increasing transition from a detoxification center to MMT enrollment and participation. A lager sample will be required to elucidate the severity (e.g., level of heroin use, HIV status) or enabling (e.g., perceived effectiveness of prior MMT or attitudinal changes after MMT) factors that may mediate or explain the association between prior MMT use and subsequent MMT participation.
Internationally, many studies have shown that out-of-treatment heroin addicts face many barriers to entry into MMT programs, including a long waiting list, lack of money or health insurance, beliefs about methadone’s real or rumored side effects, and fear of addiction to or later withdrawal from methadone [18–20]. Such barriers also are reported to exist for China’s opiate addicts . Hence, interventions aimed at reducing or eliminating these barriers are urgently needed. Our results suggest that prior methadone treatment experience might help heroin users overcome some of these barriers, as demonstrated by the much higher proportion of successful referrals among heroin users in the referral card plus MMT while in detoxification intervention model (25.8%). However, China’s detoxification centers and prisons presently do not allow their detainees to receive methadone treatment despite the fact that both the World Health Organization and the United Nations Office on Drugs and Crime recommend use of opiate replacement treatment for heroin addicts in prison systems . That said, China is not the only country that does not follow this guidance—at present only 29 countries, most of which are in Europe, provide opiate replacement therapy in their prison systems [22, 23].
Unfortunately, heroin addicts in prison continue to be at high risk of acquiring blood-borne infections [24–27]. One study conducted in China has shown that injecting drug use behaviors are present among heroin addicts in detoxification centers . Although it cannot be determined from the data whether HIV infections occurred prior to or during their terms in the detoxification centers, a relatively high proportion (30.1%) of participants in this study were HIV-positive. The high prevalence of HIV infection coupled with possible drug-related risk behaviors all point to a need for including addiction treatment (e.g., MMT) in detoxification centers. Of note, a higher proportion of HIV-positive heroin addicts (16.2%) were successfully referred to MMT as compared to HIV-negative subjects (7.0%) in our study. Although this result is descriptive and based on a small sample of HIV-positive participants (n = 68), it provides some evidence upon which future research studies can be based to test and refine referral models aiming to improve engagement in MMT after detoxification center release.
This study has several limitations. First, the sample size is small and the study sites are limited to Dehong prefecture. Therefore, the generalizability of this study may be limited. Second, we only examined whether heroin addicts successfully enrolled and participated in MMT. Some proportions of those who did not may have engaged in needle exchange programs or other treatment programs, such as buprenorphine treatment. Third, the intervention was not randomly assigned to detoxification centers, therefore the baseline characteristics of study subjects in the three intervention models were not balanced. Although our analyses adjusted for characteristics that differed across centers, we may not have been able to balance out all site-related differences. Thus, some selection bias may have remained. Fourth, there might some other important factors that could influence successful referral such as family supports were not collect by this study.