Transition to injecting drug use in Iran: A systematic review of qualitative and quantitative evidence

• The Age of First injection (AFI) reported in Iran is higher than what has been reported in other countries.
• No specific change can be observed in the AFI in these studies conducted from 1998 to 2011.
• Most studies in the review reported an average of 6–7 years of drug use before starting to use injections.
• The long interim period is an opportune time for preventing mechanisms of the transition to injection use in Iran.
• An average of 17.6% of PWID initiated their drug use by injecting which is higher than some other countries.

BackgroundInjection drug use, a behavior associated with significant adverse health effects, has been increasing over the past decade in Iran. This study aims to systematically review the epidemiological and qualitative evidence on factors that facilitate or protect the transition to injection drug use in Iran.MethodsWe conducted electronic searches in five international (Medline, Web of Science, EMBASE, CINAHL, PsycINFO), one regional (IMEMR) and three Iranian (Iranmedex, Iranpsych, IranDoc) databases, as well as contacting experts in the field. Two trained researchers screened documents to identify relevant studies and independently dual-extracted data following pre-specified protocol. We applied principles of thematic analysis for qualitative data and applied a random effect meta-analysis model for age of first injection.ResultsA total of 38 documents from 31 studies met eligibility criteria, from which more than 50% were implemented from 2006 to 2008. The weighted mean age of first injection was 25.8 (95% Confidence Interval: 25.3–26.2). Between 1998 and 2011, the age of first injection was relatively stable. Overall, drug users had used drugs for 6–7 years before they started injection use. Heroin was the first drug of injection in the majority of the cases. We identified factors influencing the initiation of or transition to injection use at various levels, including: (1) individual (pleasure-seeking behavior, curiosity and development of drug dependency commonly reported), (2) social and environmental (role of peer drug users in the first injection use, the economic efficiency associated with injections and the wide availability of injectable form of drugs in the market).ConclusionHarm reduction policies in Iran have almost exclusively focused on drug injectors in Iran. However, given the extent of the non-injection drug use epidemic, evidence from this study can provide insight on points of interventions for the prevention of the transition to injection use.