First objective association between elevated carbohydrate-deficient transferrin concentrations and alcohol-related traffic accidents

Background: Carbohydrate-deficient transferrin (CDT) is a well-recognized highly specific marker of chronic alcohol abuse. The association of CDT with alcohol-related traffic accidents was evaluated to objectively validate the use of this marker for certifying the physical fitness for driving license regranting after its confiscation for drunk driving. Methods: The study was carried out on 468 injured drivers (InjDr), who underwent mandatory blood alcohol concentration (BAC) and drug analysis in biological fluids. The InjDr group was divided into 2 subgroups on the basis of BAC legal limit adopted in Italy (BAC ≤ 0.5 g/l: InjDr1; BAC >0.5 g/l: InjDr2). The control group (CntDr) included 236 subjects holding safety-sensitive job positions and undergoing mandatory toxicological analyses. The determination of BAC in blood and CDT in serum were performed using validated analytical methods based on head-space gas chromatography and high-performance liquid chromatography, respectively. Results: The evaluation of CDT distribution in the 3 groups (CntDr, InjDr1, InjDr2) showed that CDT distribution in the InjDr1 group was similar to that observed in the CntDr group (p = 0.159) and different from that observed in the InjDr2 group (p < 0.001). Partitioning the CDT data of each group into "CDT positives" and "CDT negatives" on the basis of the cut off (1.90%), it was possible to calculate the odds of the 3 groups and then the odds ratios. The odds ratio of InjDr1 versus CntDr was 4.56 (p = 0.158), whereas the odds ratio of InjDr2 versus CntDr was 132 (p < 0.001). Furthermore, a dose-response effect was found only when comparing InjDr2 with CntDr. Conclusions: The data of the present study strongly support the use of the CDT test to evaluate the risk of a subject to be involved in a road accident while driving under the influence of alcohol.