PLoS ONE (Jan 2006)

Hyperhomocysteinemia and mortality after coronary artery bypass grafting.

  • Domenico Girelli,
  • Nicola Martinelli,
  • Oliviero Olivieri,
  • Francesca Pizzolo,
  • Simonetta Friso,
  • Giovanni Faccini,
  • Claudia Bozzini,
  • Ilaria Tenuti,
  • Valentina Lotto,
  • Giuliano Villa,
  • Patrizia Guarini,
  • Elisabetta Trabetti,
  • Pier Franco Pignatti,
  • Alessandro Mazzucco,
  • Roberto Corrocher

DOI
https://doi.org/10.1371/journal.pone.0000083
Journal volume & issue
Vol. 1
p. e83

Abstract

Read online

BACKGROUND: The independent prognostic impact, as well as the possible causal role, of hyperhomocysteinemia (HHcy) in coronary artery disease (CAD) is controversial. No previous study specifically has addressed the relationship between HHcy and mortality after coronary artery bypass grafting (CABG) surgery. The aim of this study is to evaluate the prognostic impact of HHcy after CABG surgery. METHODOLOGY AND PRINCIPAL FINDINGS: We prospectively followed 350 patients who underwent elective CABG between May 1996 and May 1999. At baseline, fasting total homocysteine (tHcy) levels were measured in all participants, and a post-methionine loading (PML) test was performed in 77.7% of them (n = 272). After a median follow-up of 58 months, 33 patients (9.4%) had died, 25 because of cardiovascular events. HHcy, defined by levels higher than the 90th percentile (25.2 micromol/L) of the population's distribution, was significantly associated to total and cardiovascular mortality (P = 0.018 [log-rank test 5.57]; P = 0.002 [log-rank test 9.76], respectively). The PML test had no prognostic value. After multiple adjustment for other univariate predictors by Cox regression, including statin therapy (the most powerful predictor in uni-/multivariate analyses), high-sensitivity C Reactive Protein (hs-CRP) levels, and all known major genetic (MTHFR 677C-->T polymorphism) and non-genetic (B-group vitamin status and renal function) tHcy determinants, HHcy remained an independent prognostic factor for mortality (HRs: 5.02, 95% CIs 1.88 to 13.42, P = 0.001). CONCLUSIONS: HHcy is an important prognostic marker after CABG, independent of modern drug therapy and biomarkers.