Serum Gamma Glutamyltransferase (GGT) in coronary artery disease: Exploring the Asian Indian Connection.

Background: There is a need to identify novel markers for CAD, independent of traditional CV risk factors. One of these is gamma-glutamyl transferase (GGT), a marker of increased oxidative stress. Given the high prevalence of CAD in Asian Indians, the link of GGT and CAD in them needs to be studied. Aim: To assess GGT in patients with angiographically documented CAD. Methods and Results: Two hundred patients aged 58.1 ± 9.95 years, 73% males, hypertension 56%, diabetes 40% were included. Mean GGT was 63.6 ± 44.33 (10-269 U/L). The levels of GGT progressively increased in those with single/double or triple-vessel CAD (36.5, 61.5, and 87 U/L, respectively, P < 0.001). Using objective criteria of CAD burden (SYNTAX and Gensini scores), we reaffirmed these findings. GGT in patients with SYNTAX tertiles 0-22, 23-32, and ≥ 33 was 33, 62, and 97 U/L, respectively and in Gensini tertiles 0-17.65, 17.66-56.65, ≥56.66 was 32, 52, and 88 U/L, respectively, all P < 0.001. SYNTAX score ≥ 23 was present in only 23% patients in GGT tertile 1 (<41 U/L), whereas60% and 94% in GGT tertiles 2 and 3 had SYNTAX ≥ 23. Significant positive correlation was seen between GGT and SYNTAX (r = 0.634) and Gensini score (r = 0.772). Conclusions: In this study, GGT had an independent correlation with angiographic severity of CAD and SYNTAX and Gensini scores. Although the existing evidence seems biologically plausible, more studies are needed to explore the potential role of this inexpensive marker for predicting disease burden in patients with CAD.