Prevalence of Alcohol and Drugs in Fatal Road Traffic Injuries (RTIs) in a Thai Population Between 2018 and 2023

OBJECTIVE To determine and compare the prevalence of alcohol, drugs of abuse and medicines in fatal road traffic injuries (RTIs) in Thailand from 2018 through 2023. METHODS A retrospective study was conducted of fatal RTI cases sent for autopsy at the Department of Forensic Medicine, Siriraj Hospital, Mahidol University from 2018 through 2023. Subject data, including sex, age, type of RTI case, blood alcohol concentration (BAC), and urine drug profile, were collected. Descriptive statistics, Chi-square tests, Mann–Whitney U tests, and Kruskal–Wallis H tests were performed as appropriate. RESULTS From 2018 through 2023 a total of 1,979 fatal RTI cases were included in this study. Of those cases, 1,649 were male (83.3%) and the mean subject age was 37.3 years. The yearly prevalence of driving under the influence (DUI) of alcohol (BAC > 50 mg/dL) during the study period was between 45.80% and 53.40% with the exception of 2022, which showed a significant increase at 57.10% (p < 0.05). The prevalence of drugs in 2023 was 21.00%, a significant difference compared with the prevalence in 2018 of 13.70% (p < 0.05). The prevalence of cannabis use showed an increasing trend, with a statistically significant increase in 2023 (p < 0.05). The prevalence of multiple drug use also significantly increased over the study period, particularly in 2023 (p < 0.05). CONCLUSIONS The prevalence of drugs of abuse and medication in fatal RTI cases markedly increased over the study period, particularly in 2023. There was a significant increase in cannabis use and poly-drug use in fatal RTI cases over the period, especially in 2023.