Superior performances of CDT as a biomarker of alcohol abuse associated to alcohol-related traffic accidents

Background-aim The fitness to hold the driving license, particularly in case of a previous confiscation for drunk driving, is generally based on a clinical visit supported by the evaluation of biomarkers associated with clinically relevant chronic alcohol abuse. Unfortunately, very little is known on the real association between these biomarkers and the occurrence of alcohol-related road accidents. The present is one of the first studies aimed specifically at unravelling this intricate problem, which is crucial for the validation of any biomarker-based medical certification of the fitness to hold the driving license (or to do safety sensitive jobs). Methods The investigated biomarkers were: CDT (analyzed by using HPLC); MCV and ©GT (analyses performed on automated clinical chemistry instrumentation); and EtG (analyzed by employing GCQqQ MS). Blood alcohol concentration (BAC) analysis was performed by head-space GC with FID detection. Subjects: CDT was studied in 468 individuals injured in car crashes, 368 of whom had a BAC δ0.5 g/L and 100 N 0.5 g/L. MCV was studied in 6244 subjects, of whom 2718 had a BAC δ0.5 g/L and 3526 a BAC N0.5 g/L. ©GT was investigated in 393 individuals, 312 of whom had a BAC δ0.5 g/L and 81 a BAC N0.5 g/L. Finally, 53 individuals dead in car crashes were studied for EtG in hair (hEtG), 35 of whom showed a BAC δ0.5 g/L vs. 18 had a BAC N0.5 g/L. Results When comparing CDT and BAC analysis, a neat statistical significance was observed by obtaining a chi square value of 74.76 (p b .001) with an odds ratio of 30. The association between MCV and BAC provided a chi square of 68.0 (p b .001) and an odds ratio of 1.81. In the comparison between ©GT and BAC, the chi square was 25.48 (p b .001) with an odds ratio of 5.16. With regards to hEtG, the Fisher test resulted in a p value of ~ 0.05. Conclusions All studied biomarkers provided statistically significant results in the association of drunk driving and traffic accidents. Nevertheless, CDT showed the best figures in terms of odds ratio (ranging from 30 to 100), supporting its high strength of association with the risk of traffic accidents. On these grounds, CDT proved as the most useful biomarker in the process of re-granting the driving license after its confiscation for drunk driving