Abstract
Objective: γ-glutamyl transferase (GGT) has long been regarded as a marker for excessive alcohol consumption or hepatobiliary disease and there is known to be a close relationship between obesity and serum GGT from epidemiological studies. Recently, many studies have reported GGT as a risk factor for cardiovascular disease mortality. Also, nonalcoholic fatty liver disease (NAFLD) has been seen to be associated with an increased incidence of cardiovascular events. In this study, we investigated a relationship between NAFLD detected by ultrasound and serum GGT in health check-up subjects.
Subjects and Methods: 1,000 subjects were chosen at random from 17,069 persons undergoing health check-ups at our clinic in 2009. Still images were recorded by 5 sonographers using a commercially available ultrasonoscope (Toshiba XarioTM XG) and later diagnosed by a certified fellow of JSUM in accordance with our criteria for fatty liver.
Results: Serum GGT levels in NAFLD tended to rise in association with the degree of fatty change and there was a fair correlation, r = 0.562 ( p < 0.001 ), between serum GGT and serum ALT. In 76.8% of the detected NAFLD, GGT levels were normal (≤50IU/L) and the close association between fatty change and GGT even extended into the normal range. A small proportion (1.4 %) of subjects had isolated GGT elevation (ALT≤30IU/L) of unknown mechanism.
Conclusion: In the health check-up subjects, there was a close association between NAFLD and serum GGT with the correlation even extending into its normal range (≤50 IU/L). Unknown mechanisms of GGT elevation seemed to be present.
