Descriptive epidemiology of acute liver enzyme abnormalities in the general population of central Massachusetts

Objectives: This study quantifies the incidence of liver enzyme abnormalities in the general population of central Massachusetts.

Methods: Computerized data files from a health maintenance organization were used to ascertain potential subjects during the study period of 1 July 1992-30 June 1993. Medical records and laboratory tests results were reviewed to confirm the diagnoses.

Results: The incidence rates were 40.6 cases per 100,000 persons per year for drug-associated liver enzyme abnormalities, 39.0 per 100,000 persons per year for liver enzyme abnormalities secondary to biliary pathologies, 25.2 per 100,000 persons per year for liver enzyme abnormalities secondary to mononucleosis, 25.2 per 100,000 persons per year for liver enzyme abnormalities of unknown aetiology, 15.4 per 100,000 persons per year for alcoholic liver enzyme abnormalities, 12.2 per 100,000 persons per year for liver malignancy, and 7.3 per 100,000 persons per year for viral hepatitis (HAV, HBV and HCV). Men were more commonly affected by alcoholic liver enzyme abnormalities and viral hepatitis, with respective incidence rates approximately 5 and 2 times higher than women. Liver enzyme abnormalities secondary to mononucleosis occurred predominantly between the ages of 15-24 years. In contrast, liver diseases secondary to biliary pathologies, liver malignancies and drug-associated liver enzyme abnormalities were found most frequently among the elderly.

Conclusion: Liver enzyme abnormalities occurred with a higher incidence in this general population than reported previously in selected patients. Drug-associated liver enzyme abnormality was the most common type. The magnitude of drug-associated liver enzyme abnormality could be much higher as an appreciable proportion of the liver cases of unknown aetiology are potentially drug-attributable.