The toxicology of heroin-related death: estimating survival times

Background and aimsThe feasibility of intervention in heroin overdose is of clinical importance. The presence of 6-monoacetyl morphine (6MAM) in the blood is suggestive of survival times of less than 20-30 minutes following heroin administration. The study aimed to determine the proportions of cases in which 6MAM was present, and compare concentrations of secondary metabolites and circumstances of death by 6MAM status. DesignAnalysis of cases of heroin-related death presenting to the Department of Forensic Medicine Sydney, 1 January 2013-12 December 2014. SettingSydney, Australia. CasesA total of 145 cases. The mean age was 40.5years and 81% were male. MeasurementsConcentrations of 6MAM, free morphine, morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). Circumstances of death included bronchopneumonia, apparent sudden collapse, location and other central nervous system (CNS) depressants. Findings6MAM was detected in 43% [confidence interval (CI)=35-51%] of cases. The median free morphine concentration of 6MAM-positive cases was more than twice that of cases without 6MAM (0.26 versus 0.12mg/l). 6MAM-positive cases also had lower concentrations of the other major heroin metabolites: M3G (0.05 versus 0.29mg/l), M6G (0.02 versus 0.05mg/l) with correspondingly lower M3G/morphine (0.54 versus 2.71) and M6G/morphine (0.05 versus 0.50) ratios. Significant independent correlates of 6MAM were a higher free morphine concentration [odds ratio (OR)=1.7], a lower M6G/free morphine ratio (OR=0.5) and signs of apparent collapse (OR=6.7). ConclusionsIn heroin-related deaths in Sydney, Australia during 2013 and 2014, 6- monoacetyl morphine was present in the blood in less than half of cases, suggesting that a minority of cases had survival times after overdose of less than 20-30 minutes. The toxicology of heroin metabolites and the circumstances of death were consistent with 6- monoacetyl morphine as a proxy for a more rapid death.