Effects of alcohol intake and obesity on serum liver enzyme activity in obese men with mild hypertension

Abstract
To examine the relationships between alcohol intake, obesity, plasma insulin concentration and serum activities of three liver enzymes in obese men with mild hypertension. A 6-week run-in period followed by randomization to either diet treatment or antihypertensive drug treatment, lasting for 1 year. Alcohol intake was estimated using questionnaires. Plasma insulin concentration, serum activities of gamma-glutamyl transferase, and aspartate and alanine aminotransferase, respectively, were measured at entry and after 1 year. Out-patient clinic, city hospital. Sixty-four men aged 40-69 years with a body mass index > or = 26 kg m-1 and with mild untreated hypertension. Exclusion criteria were alcoholism and diabetes mellitus. Sixty-one patients completed the study. Dietary treatment was based upon weight reduction and recommendations about a low alcohol intake. Drug treatment used a stepped-care approach with atenolol as the first-choice drug. Serum activities of the liver enzymes, body weight, body mass index, alcohol intake, plasma insulin concentration. Body weight decreased by 7.8 kg in the diet group and increased by 1.0 kg in the drug-treated group. Alcohol intake did not differ between the groups before or after 1 year. Serum gamma-glutamyl transferase activity correlated with alcohol consumption; it showed no significant change after weight loss. At entry, serum activities of aspartate and alanine aminotransferases correlated to plasma insulin concentration independent of body mass index. Weight reduction significantly lowered serum activities of these liver enzymes as well as plasma insulin concentrations and normalized elevated serum activity of alanine aminotransferase in a majority of the cases. Alcohol intake was an important determinant for elevated serum gamma-glutamyl transferase activity. The degree of obesity was a contributing factor for elevations of serum alanine aminotransferase activity. We speculate that insulin may play a role in this relationship.