New evidence of high association between carbohydrate deficient transferrin (CDT) and alcohol-related road traffic accidents. A retrospective study on 929 injured drivers

Nadia M Porpiglia, Franco Tagliaro, Rocco Micciolo, Luisa Canal, Giacomo Musile, Federica Bortolotti

Background: It is well known that traffic injuries still represent one of the main causes of death and that high blood alcohol concentrations while driving significantly increase the occurrence of accidents. However, only limited literature on the correlation between chronic alcohol abuse and accident risk is available. The aim of the present study was to investigate the hypothesis of an association between elevated concentrations of carbohydrate deficient transferrin (CDT) and the occurrence of alcohol-related traffic accidents.

Methods: The analytical determinations of BAC and CDT were performed following certified methods in HS-GC-FID and HPLC, respectively. For BAC, 0.50 g/L was used as cut-off, whereas 2.0% was used for CDT, according to the standardisation proposed by IFCC. A total of 929 drivers, tested for BAC at the time of hospital admission after a traffic accident, were classified into two groups: InjDr 1 (BAC ≤ 0.50 g/L) and InjDr 2 (BAC>0.50 g/L); all drivers were also tested for CDT.

Results: InjDr 1 included 674 individuals, only 2.5% showing a CDT above the cutoff, whereas InjDr 2 group consisted of 255 subjects, 28.6% testing positive for CDT (Odds Ratio 15.5). When subdividing the InjDr group into increasing classes of CDT, a steady increase in the percentage of BAC-positive drivers was appreciated. Moreover, average BAC was found to parallel each class of CDT.

Conclusions: The reported data strongly support the use of CDT as a biomarker of increased risk of alcohol-related traffic accidents in the procedures of re-granting of the driving license upon confiscation for “drink driving”.

Keywords: Alcohol-related road traffic accidents; Blood alcohol concentration; Carbohydrate deficient transferrin; Forensic toxicology; Traffic medicine.