Objective: Increased serum gamma-glutamyl transferase (GGT) activity is known to be associated with atherosclerotic diseases. Thoracic aortic intima-media thickness (IMT) was reported as a marker of preclinical atherosclerosis. However, there is a lack of research directly examining the relationship between serum GGT activity and thoracic aortic IMT. Therefore, we aimed to investigate the association between serum GGT activity and thoracic aortic IMT.
Patients and methods: The study population consisted of 329 patients without coronary artery disease, who underwent transesophageal echocardiography (TEE) examination for various indications from January 2011 to April 2013. GGT, high-sensitivity C-reactive protein (hs-CRP) and other biochemical markers were measured in all patients. The patients were classified into tertiles according to their GGT activities (GGTlow < 19 U/l, GGTmid ≥ 19 U/l < 29 U/l, and GGThigh ≥ 29).
Results: The highest aortic IMT values were observed in the GGThigh group compared with the GGTmid and GGTlow groups (p < 0.05, for all). Also, aortic IMT values in the GGTmid group were higher than in the GGTlow group (p < 0.05). Multivariate regression analysis showed that GGT activity was independently associated with aortic IMT (β = 0.487, p < 0.001) hs-CRP (β = 0.282, p < 0.001), and triglyceride level (β = 0.161, p = 0.007).
Conclusion: The higher serum GGT concentrations within the "normal" range were associated with a greater IMT of the thoracic aorta. GGT activity may be a predictor of the extent of subclinical aortic atherosclerosis assessed with thoracic aortic IMT.