Association of gamma-glutamyltransferase with cardiovascular risk: a prognostic outlook.

gamma-Glutamyltransferase (GGT), an enzyme responsible for the extracellular catabolism of antioxidant glutathione, may explicitly participate in atherogenesis. Several population-based studies have documented strong cross-sectional associations between serum GGT concentrations and certain cardiovascular risk factors, irrespective of alcohol consumption. The mechanism underlying these associations remains largely enigmatic. Considerable association of high-sensitivity C-reactive protein, a major inflammatory marker for cardiovascular risk, with GGT and other cardiovascular risk factors has been described, implying that elevation of serum GGT (conceivably acting as a marker of oxidative stress) is correlated with subclinical microinflammatory response involved in the pathogenesis of atherosclerosis. It is also relevant to assess whether the prognostic impact of a novel risk marker can be influenced by therapeutic intervention, thus decreasing the occurrence of cardiovascular events. Subtle gradations in serum GGT may help predict long-term cardiovascular prognosis, and the supplementary GGT determination to conventional testing has potential implications for screening those at increased cardiovascular risk who may benefit from prophylactic measures and require enhanced therapeutic effort. It has been reported that serum GGT may contribute to the accumulation of GGT activity inside the plaque. Further comprehension is, however, needed about the relationship of GGT activity inside the plaque with inflammatory biomarkers, plasma lipoproteins, and other independent determinants to define the most risky combination and improve the prognostic stratification of patients.