Serum apolipoprotein A-II as a marker of change in alcohol intake in male drinkers.

The relative usefulness of high-density lipoprotein cholesterol (HDL-C) and the HDL components, apolipoproteins A-I and A-II (Apo A-I and Apo A-II), as prospective markers of change in alcohol intake was compared to gamma-glutamyl transferase (gamma GT) and erythrocyte mean corpuscular volume (MCV) in a controlled crossover trial of 46 moderate male drinkers whose alcohol intake was reduced by approximately 80% for six weeks by the substitution of their normal drinking habits for a low alcohol content beer only. Only serum Apo A-II levels correlated significantly with self-reported alcohol intake at the commencement of the study (r = 0.46; P less than 0.001). All five indices fell significantly with reduction of alcohol intake. The change in these indices between normal and low alcohol intake periods correlated directly with change in alcohol intake, the highest correlation being with delta Apo A-II (r = 0.72; P less than 0.001). Using discriminant analysis this variable was found to achieve an accuracy of 96% in classifying subjects into the correct drinking category (either normal or low alcohol intake). The relative percentages for the other variables were delta Apo A-I 78%, delta HDL-C 82%, delta gamma GT 78% and delta MCV 76%. We conclude that Apo A-II may prove a valuable marker of alcohol intake in cross-sectional epidemiological studies, while delta Apo A-II may be a sensitive marker of change in alcohol intake in the prospective management of the heavy drinker.