Research in other countries has shown that individuals recently released from prisons who use opiates are at elevated risk to experience fatal and non-fatal heroin overdoses compared with active opiate users [31
]. The WHO has recommended that pre-release overdose prevention, including the use of naloxone for those released drug users and others in their social networks [36
Results from this survey support the idea that overdose prevention training, including naloxone distribution, is needed and wanted in the region. A high percentage of surveyed heroin users lack accurate information related to overdose response. In particular, participants choose "injecting salt water", a strategy that has been proven to be ineffective [37
], as an effective way to respond to an overdose at a rate more than one and a half times higher than calling 120 (emergency), five times higher than the rate of performing mouth to mouth resuscitation, and nine times higher than administering naloxone. That accurate information about overdose response is lacking among many heroin users in Ningbo is not surprising given that to date there have been no peer-focused harm reduction activities, including overdose prevention intervention, in the region.
The survey data also shows that there is an interest in overdose prevention and response interventions among detained drug users. Between 64% and 88% of participants in the survey indicated that overdose was a concern in their own lives and, that they would be willing to attend a training program on overdose prevention, help peers administer naloxone, and share information they learned about these services. This finding mirrors international studies that have found that most drug users are willing to help peers [38
Approximately a third of Ningbo respondents reported having accidently overdosed in the past, 37.7% witnessed an overdose, and close to 40% reported having someone who they knew die of an overdose. These numbers are lower than drug user reports of witnessing an overdose in San Francisco (89%) [40
], sixteen cities throughout Russian federation (81%) [5
], and London (81%) [41
]. In Gejiu, China, approximately 90% of drug users surveyed had witnessed overdoses (unpublished data, author communication). In Kunming, China, 34% of respondents recruited from a methadone maintain clinic recently reported being at the site of an overdose of an acquaintance within the last year, nearly three times the number of our Ningbo participants (11.9%) (personal communication, unpublished data). There are a number of factors that may account for the relatively lower occurrence of overdose in Ningbo, such as lower proportion of opiate users injecting (less than 37% of those surveyed indicated that they injected), less mixing of drugs, and relatively low purity of heroin in the region. This underscores the fact that while there is a definite need for overdose prevention and response in Ningbo, there may be even greater need in other parts of the country, where a variety of factors may result in higher number of overdoses.
There are several limitations of this study's methodology that need to be addressed here. Generalization of these results must be made with caution as Ningbo's heroin using population and drug treatment services may not be representative of compulsory detoxification centers in other parts of the country. In addition, the study did not attempt to collect more details of participants' drug use history, information about poly-drug use, or other risk factors that could better identify the specific risk factors associated with overdose among this population. Furthermore, a simple and broad definition of heroin overdose was used in the questionnaire, due to the educational level of the participants. It is possible that this definition of overdose might bias the prevalence estimated here. In the future, more detailed research is needed to better understand what are the risk factors associated with heroin overdoses in Ningbo, where overdose deaths are occurring, and which demographics of heroin users are currently at highest risk. Future studies should recruit in multiple settings to attempt to recruit a more representative sample of those at risk of overdosing.
Despite these limitations, our survey provides preliminary evidence that detaind drug users in Ningbo have considerable interest in overdose prevention and response information and willingness to help peers. However, detained drug users in Ningbo isolated compulsory detoxification centers currently have limited understandings of effective ways of helping to prevent overdose deaths. According to the recent China Drug Control Law, drug dependent patients are required to receive isolated compulsory detoxification for between one and 3 years [42
]. Our study indicates that survey respondents had rather limited amount of overdose prevention related information. It should also be noted that relapse rates among individuals released from the isolated compulsory detoxification centers have been found to be extremely high [29
]. Taken together, we believe that Ningbo isolated compulsory detoxification centers could adopt an overdose prevention and response curriculum in compulsory detoxification centers, including pre-release coordination of prelease distribution of naloxone.