A new biological alcohol marker, the ratio between the acetaldehyde-induced haemoglobin fraction HbA1ach and the glycated haemoglobin fraction HbA1c (HbA1ach/HbA1c), was studied in association with data obtained in a questionnaire, the Malmo modified Michigan alcoholism screening test (Mm-MAST), completed by 270 consecutive middle-aged men participating in a voluntary health screening. None of them had earlier alcoholic health or alcohol-dependent social problems. The nine-question Mm-MAST correlated positively with the ratio of HbA1ach/HbA1c (r = 0.272, P < 0.001). In the three drinker groups defined according to the questionnaire, HbA1ach/HbA1c values were significantly higher among heavy drinkers (mean = 40, S.E.M. = 1) than among teetotallers (mean = 32, S.E.M. = 2, P < 0.01) or social drinkers (mean = 35, S.E.M. = 1, P < 0.01). In the groups formed according to the respondents' own alcohol anamnesis there was no significant difference between the marker values, but the Mm-MAST score was significantly higher in both social (P < 0.001) and heavy drinkers' (P < 0.001) groups as compared with teetotallers. This shows that the questionnaire detected heavy drinkers better than the self-given anamnesis. The correlation of HbA1ach/HbA1c and the questionnaire means that the biological marker studied represents a new possibility to identify heavy drinkers before alcoholic health problems or social consequences have appeared.
