Relationship between γ-glutamyltransferase and metabolic syndrome in a Korean population

Aims: To investigate associations between γ-glutamyltransferase (GGT) and components of metabolic syndrome (MS), insulin resistance and inflammatory markers in the Korean population. Methods: The 3508 subjects enrolled in this survey participated in the Korean Rural Genomic Cohort (KRGC) study. Written consent was obtained from the local ethical committee. Of these participants, 1437 were men (mean age 56.9 ± 7.9 years) and 2071 were women (mean age 55.8 ± 8.1 years). We measured GGT levels and various biochemical markers. To examine insulin resistance status, we used the homeostasis assessment method for insulin resistance (HOMA-IR). For inflammatory marker, we used C-reactive protein (CRP) levels. Results: Serum GGT levels were significantly higher in the MS group compared to the healthy patient group [23 (5-1403) vs. 19 (5-1920) IU/l; P = 0.01]. The prevalence of MS and adjusted relative risk were both significantly increased from the lowest to highest GGT quartiles; these results persisted after adjustments for multiple confounders. Positive correlations were established between GGT and HOMA-IR or CRP. Conclusion: These results suggest that GGT levels may be a surrogate marker of insulin resistance, inflammation and MS.