BACKGROUND: Carbohydrate-deficient transferrin (CDT) and gamma-glutamyl transferase (GGT) are used as biomarkers of alcohol misuse. The aim of this study was to evaluate, in terms of sensitivity and specificity, the performance of the new Bio-Rad %CDT TIA kit and GGT assay for identifying alcohol abuse and alcohol dependence (according to the DSM-IV criteria). METHODS: An open multicenter study (30 centers) over 3 months, including patient groups of "abusers," "dependents," and controls, was conducted in France. RESULTS: In alcohol abuse, the sensitivity of GGT was 0.56, and that of CDT was 0.80; in alcohol dependence, the sensitivity of GGT was 0.86, and that of CDT was 0.91. The specificity of GGT was 0.77, and that of CDT was 0.83. The association of GGT with CDT increased sensitivity for alcohol abuse to 0.90 and for alcohol dependence to 0.99, but it appreciably decreased specificity (0.63). CONCLUSIONS: %CDT is the better screening marker for alcohol abuse and dependence, but GGT is still a useful marker for the detection of alcohol dependence. As an assay method, the second-generation Bio-Rad %CDT immunoassay can be recommended for routine CDT measurement.
BACKGROUND:Carbohydrate-deficient transferrin (CDT) and gamma-glutamyl transferase (GGT) are used as biomarkers of alcohol misuse. The aim of this study was to evaluate, in terms of sensitivity and specificity, the performance of the new Bio-Rad %CDT TIA kit and GGT assay for identifying alcohol abuse and alcohol dependence (according to the DSM-IV criteria). METHODS: An open multicenter study (30 centers) over 3 months, including patient groups of "abusers," "dependents," and controls, was conducted in France. RESULTS: In alcohol abuse, the sensitivity of GGT was 0.56, and that of CDT was 0.80; in alcohol dependence, the sensitivity of GGT was 0.86, and that of CDT was 0.91. The specificity of GGT was 0.77, and that of CDT was 0.83. The association of GGT with CDT increased sensitivity for alcohol abuse to 0.90 and for alcohol dependence to 0.99, but it appreciably decreased specificity (0.63). CONCLUSIONS: %CDT is the better screening marker for alcohol abuse and dependence, but GGT is still a useful marker for the detection of alcohol dependence. As an assay method, the second-generation Bio-Rad %CDT immunoassay can be recommended for routine CDT measurement.