Dose-effect relation between daily ethanol intake in the range 0-70 grams and %CDT value: validation of a cut-off value.

Aim: To evaluate the ability to infer alcohol consumption using the %CDT (carbohydrate deficient transferrin) immunoassay (Axis Shield).

Methods: One hundred and eighty-three healthy subjects (143 men, 40 women) undergoing a routine medical check-up at their workplace declared frequency and quantity of alcohol consumption covering the last 4 weeks. Seven sub-groups were made up from this population, according to daily ethanol intake and by increments of 10 g from 0 to 70 g/day. A reference group that consisted of 133 healthy teetotallers (74 men, 59 women) was recruited by occupational medicine in the same conditions as the 183 subjects of the study. Percentage CDT and gamma glutamyl transferase (GGT) were assayed on a fasting blood sample.

Results: There was a proportional dose-response effect of daily ethanol intake on %CDT values in the range of 0-70 g per day. A threshold effect on %CDT values for patients having an alcohol intake of over 40 g per day was found, an effect which was not observed for GGT activity.

Conclusion: The kit has clinical usefulness, and the value of 2.6% proposed by the manufacturer for the cut-off for hazardous drinking in both sexes has been validated.