γ-Glutamyltransferase rather than total bilirubin predicts outcome in chronic heart failure

Abstract

Background: Gamma-glutamyltransferase (GGT) and total bilirubin (T-Bil) are elevated and of prognostic significance in chronic heart failure (CHF). This study sought to compare these novel cardiovascular risk markers in CHF.

Methods and results: We evaluated 1,087 ambulatory patients from our heart failure program. Long-term follow-up was available in 1,056 patients. The combined end point was defined as death of any cause or heart transplantation. Prevalence of elevated GGT was 43% in men and 48% in women, that of T-Bil 17% and 8%, respectively. Both variables were significantly correlated with severity of heart failure. GGT and T-Bil were associated with transplant-free survival in bivariate analysis (P values <.001 and .006, respectively). However, GGT (hazard ratio [HR] 1.28, 95% confidence interval [CI] 1.13-1.44; P < .001), but not T-Bil, remained an independent predictor of prognosis in the multivariate model. Also, categorized GGT levels beyond the gender-specific normal ranges were predictive of the combined end point (HR 1.55, 95% CI 1.23-1.95). Elevation of both GGT and T-Bil further increased the risk of reaching the end point (HR 2.57, 95% CI 1.74-3.18).

Conclusions: GGT and T-Bil are associated with disease severity in CHF. However, only GGT is independently associated with adverse outcome. Our findings further highlight the clinical importance of GGT in cardiovascular disease.