Gamma-glutamyltransferase and prognosis in patients with stable coronary heart disease followed over 8 years

Background: Serum gamma-glutamyltransferase (gGT) predicts incident cardiovascular disease and mortality. The present study examined whether gGT also is associated with prognosis in patients with stable coronary heart disease. Methods: This study included 1152 participants (aged 30–70 years at baseline) of an in-patient rehabilitation programme after acute coronary syndrome, recruited in two rehabilitation clinics in Germany in the years 1999–2000 (KAROLA study). Associations of gGT with secondary events and mortality were examined using Cox regression models. Results: Until year 8 follow-up, 147 participants had experienced a non-fatal or fatal secondary cardiovascular disease event. Confounder-adjusted Cox proportional hazards models revealed an increase in risk for secondary events over ascending gGT quartiles, with hazard ratios (95% confidence interval) of 1.21 (0.72–2.03), 1.32 (0.80–2.16) and 1.75 (1.08–2.83) for the 2nd, 3rd and 4th in reference to the lowest quartile (Ptrend=0.024). The association with all-cause mortality examined as a secondary outcome was slightly stronger (hazard ratio of 4th quartile: 1.97 [1.15–3.36]; Ptrend=0.017). Conclusions: In patients with stable coronary heart disease, serum gGT was associated with prognosis independent of a variety of established risk markers. The association appeared similar to that reported for primary cardiovascular disease, which should motivate additional studies of its clinical utility in cardiovascular patient care.