Use of carbohydrate-deficient transferrin (CDT) and a combination of GGT and CDT (GGT-CDT) to assess heavy alcohol consumption in traffic medicine.
OBJECTIVE
Carbohydrate-deficient transferrin (CDT) has become widely used in traffic medicine to detect chronic alcohol abuse among subjects applying for driving-license renewal or regranting. By defining cut-off values in a large population of abstainers and moderate drinkers, we report on CDT, GGT-CDT (a combination of gamma-glutamylaminotransferase (GGT) and CDT) and the association between blood alcohol concentration (BAC) and CDT among Italian drivers.


METHODS
CDT was evaluated by a high performance liquid chromatography (HPLC)-based commercial kit in 652 abstainers or moderate drinkers, 603 drivers applying for driving-license regranting after a rehabilitation programme and 105 drivers involved in car accidents with blood alcohol concentration higher than the legal limit used in Italy (BAC >0.5g/l). GGT-CDT was calculated according to Sillanaukee and Olsson and Niemelä. BAC has been assessed by gas chromatography-mass spectrometry.


RESULTS
A common CDT cut-off (1.8%) and gender-specific GGT-CDT cut-off (4.15% for males, 3.56% for females) were calculated as 99.9th percentiles of the control population. Also, 3% and 27% of subjects were classified as CDT positive respectively among drivers applying for license regranting and drivers involved in car accidents. A significant association between BAC and both CDT values and CDT positivity was found, with a frequency up to 49% of CDT samples, suggesting chronic alcohol abuse, among drivers with BAC >2.5g/l. Concordance between CDT and GGT-CDT was only moderate (kappa = 0.44), with CDT performing better than GGT-CDT.


CONCLUSIONS
A relevant proportion of drivers with high BAC are chronic abusers. GGT-CDT, previously validated with CDT immunoassays, should not be applied to traffic medicine in its current form and its performances re-evaluated with CDT measured by HPLC.
Bianchi
Vincenza
V
Toxicology Laboratory, Department of Clinical Pathology, SS. Antonio e Biagio e C. Arrigo Hospital, Alessandria, Italy.
Ivaldi
Alessandra
A
Raspagni
Alessia
A
Arfini
Carlo
C
Vidali
Matteo
M
D000063:Accidents, Traffic; D000328:Adult; D000437:Alcoholism / Q000097:blood* / Q000175:diagnosis; D001334:Automobile Driving / Q000331:legislation & jurisprudence; D015415:Biomarkers / Q000097:blood; D002492:Central Nervous System Depressants / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D000431:Ethanol / Q000097:blood; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007558:Italy; D008297:Male; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012727:Sex Characteristics; D014168:Transferrin / Q000031:analogs & derivatives* / Q000378:metabolism; D005723:gamma-Glutamyltransferase / Q000097:blood*
D015415:Biomarkers; D002492:Central Nervous System Depressants; D011933:Reagent Kits, Diagnostic; D014168:Transferrin; C056759:carbohydrate-deficient transferrin; D000431:Ethanol; D005723:gamma-Glutamyltransferase