Use of morphine and 6-monoacetylmorphine in blood for the evaluation of possible risk factors for sudden death in 192 heroin users

Aims To detect risk factors for sudden death from heroin injection. Design Evaluation of data from forensic investigations of all fatal cases of suspected heroin death in a metropolitan area. Only cases with detectable morphine and 6-monoacetylmorphine (6-MAM) in blood were included in order to select heroin intoxication cases. Setting Stockholm, Sweden. Measurements Autopsy investigation and toxicological analysis of blood and urine; and police reports. Findings In two-thirds of the 192 cases, death occurred in public places, and mostly without any time delay. Blood concentrations of morphine ranged from 50 to 1200 ng/g, and of 6-MAM from 1 to 80 ng/g. Codeine was detected in 96% of the subjects. In the majority of cases the forensic investigation indicated polydrug use, the most common additional findings being alcohol and benzodiazepines. However, in one-quarter of the cases other drug combinations were found. Previous abstinence from heroin and use of alcohol were identified as risk factors. For 6-MAM there was also a correlation with the presence of THC and benzodiazepines. Despite a high frequency of heart abnormalities (e.g. myocarditis and focal myocardial fibrosis), these conditions did not correlate with morphine or 6-MAM blood concentrations. Conclusions We confirm that alcohol intake and loss of tolerance are risk factors for death from heroin use, whereas no connection to heart pathology was observed. Further, prospective, studies should focus on other possible risk factors.