Fatal cases with drug detection in postmortem toxicology: a retrospective study in the Bío-Bío Region, Chile (2016–2020)

Drug consumption is a recognized risk factor for morbidity and premature mortality worldwide. Toxicological findings in medico-legal death investigations provide important epidemiological insight into patterns of substance exposure within a population. This retrospective study aimed to characterize the prevalence and distribution of drugs detected in peripheral blood among decedents undergoing medico-legal autopsy in the Bío-Bío region of Chile between 2016 and 2020. Cases were identified from the regional office of the Servicio Médico Legal. Decedents were included when at least one drug was detected and confirmed in peripheral blood. A total of 678 decedents had at least one drug detected during the study period. The most frequent certified causes of death were disease (29.2%), trauma (26.8%), asphyxia (15.0%), and suicide (10.6%). Men represented 82.6% of cases and women 17.4%. The most commonly detected substances were cocaine (45.7%), benzodiazepines (28.3%), and tetrahydrocannabinol (THC) (12.7%). Ages ranged from 1 to 96 years, with 84.5% of cases older than 31 years. Benzodiazepines and amitriptyline were more frequently detected among older decedents, whereas cocaine and THC predominated in younger age groups.