Characterising opportunity to use heroin reveals new avenues for intervention: context, outcomes, and latency to initiation

Preceding initiation, opportunity to use heroin is the earliest necessary condition for heroin-related outcomes to occur. This study aimed to characterise first heroin use opportunity (prior to initiation) and to identify heroin-related outcomes associated with earlier age at first opportunity. Structured interviews were conducted with 93 opiate substitution treatment clients in UK drug and alcohol treatment clinics. The majority of participants (64.8%) reported initiating heroin use on the same day as being first presented with the opportunity to use heroin. Of those who reported early age at opportunity to use heroin, 77.4% reported this came from friends/partner/family compared with 59.3% of those who reported later opportunities. After adjustment, overdose was found to be more than twice as likely amongst those who reported first opportunity to use heroin at age 17 or under (AOR 2.82 95% CI 1.57–5.05). Findings indicate the early drug use environment is linked to later risk of overdose. Greater consideration of context surrounding heroin use opportunity may indicate mechanisms to disrupt or prevent initiation of heroin use and later drug-related harms. Given short latency to initiation, focus should be placed on preventing initiation of heroin use through injecting.