Test Characteristics of Carbohydrate-Deficient Transferrin and γ-Glutamyltransferase in Alcohol-Using Perimenopausal Women

Background: The application of biochemical markers to detect heavy alcohol use in women has shown disappointing results until now. We evaluated carbohydrate‐deficient transferrin (CDT) by the CDTcct® method and γ‐glutamyltransferase (GGT) in a large cohort of alcohol‐using perimenopausal women studied primarily for osteoporosis. Methods: CDT and GGT were measured in 431 women aged 46 to 54 years, who were selected from a large cohort (n= 8503) of pre‐, peri‐, and postmenopausal women. Their alcohol intake was known from questionnaires and face‐to‐face interviews. Three groups were constructed for statistical analysis: those drinking on average less than 7 alcoholic drinks per week (n= 103), those drinking 7 to 34 per week (n= 280), and those drinking at least 35 per week (n= 48). Results: The mean values of CDT and GGT of the three groups increased with an increasing alcohol intake, but there was a poor correlation between CDT and GGT in the complete study group (r= 0.3). The specificities of CDT and GGT were comparable, 83% and 78%, respectively. The sensitivities for CDT and GGT were 30% and 50%, respectively. A logistic regression model could assign, overall, 77% of the women correctly in relation to their alcohol intake: 43% of the women drinking at least 35 drinks per week and 92% of the women drinking less than 7 drinks per week. Conclusions: The test characteristics of both GGT and CDT are not good enough to be used as biochemical markers for detecting heavy alcohol use in women. The use of a logistic regression model offers an advantage, because both numeric values of CDT and GGT are taken into account instead of arbitrary cutoff values.