Correlates and reference limits of plasma gamma-glutamyltransferase fractions from the Framingham Heart Study

Abstract

Background We assessed GGT fractions correlates and their reference values in the Offspring Cohort of the Framingham Heart Study. Methods Correlates of GGT fractions were assessed by multivariable regression analysis in 3203 individuals [47% men, mean age (SD): 59 (10) yrs.]. GGT fractions reference values were established by empirical quantile analysis in a reference group of 432 healthy subjects [45% men, 57 (10) years]. Results Fractional GGT levels were higher in men than in women (P < 0.0001). In both sexes, fractions were associated with: triglycerides were associated with b-GGT, alcohol consumption with m-, s- and f-GGT. C-reactive protein with m- and s-GGT, while plasminogen activator inhibitor-1 with b- and f-GGT. Body mass index, blood pressure, glucose and triglycerides correlated with b- and f-GGT. In comparison with the reference group [b-GGT/s-GGT median (Q1-Q3): 0.51 (0.35-0.79) U/L], subjects affected by cardiovascular disease or diabetes showed no change of b/s ratio [0.52 (0.34-0.79) U/L, 0.57 (0.40-0.83) U/L, respectively]. The b/s ratio was higher in presence of metabolic syndrome [0.61 (0.42-0.87) U/L, P<0.0001], while lower in heavy alcohol consumers [0.41 (0.28-0.64) U/L, P<0.0001]. Conclusions Metabolic and cardiovascular risk markers are important correlates of GGT fractions, in particular of b-GGT.

b-Gamma-glutamyltransferase activity in human vulnerable carotid plaques

“…This observation adds to findings from population studies showing the highest predictive value of serum total GGT activity for cardiovascular events at mediumehigh levels within normal 25e50 U/L reference range [17,20,21]. Metabolic and cardiovascular risk markers are important correlates of GGT fractions, in particular of b-GGT in healthy subjects [42] and in Framingham population [43]. It is noteworthy that non-alcoholic fatty liver disease, a component of the metabolic syndrome which is associated to increased cardiovascular risk [44], seems to be a rather specific cause of plasma b-GGT increase in blood [45], while alcohol abuse and liver diseases are more specifically associated with s-GGT elevation [46].…”

Circulating gamma glutamyltransferase and prediction of cardiovascular disease

“…It has been recently reported that GGT is made up of four fractions namely big-GGT (b-GGT), medium-GGT (m-GGT), small-GGT (s-GGT), and free-GGT (f-GGT), with each having its own molecular weight and distinct physiochemical property [30]. Of these fractions, the b-GGT fraction is known to correlate strongly with conventional cardiovascular and metabolic risk markers [31] and is the only one found in the atherosclerotic plaque [29].…”

Gamma-Glutamyltransferase Fractions in Human Plasma and Bile: Characteristic and Biogenesis

“…While f-GGT is the most abundant fraction in healthy adults [18], the three high MW fractions (b-, m- and s-GGT) are increased in liver diseases [19]. The first study on diagnostic specificity of the four GGT fractions showed that the latter are present also in patients with non-alcoholic fatty liver diseases (NAFLD), chronic viral hepatitis C [19] or alcoholic liver disease [20], but in different quantities.…”