Hyperhomocysteinemia is an independent predictor of long-term clinical outcomes in Chinese octogenarians with acute coronary syndrome

OBJECTIVE To evaluate the prognostic value of homocysteine (Hcy) in Chinese acute coronary syndrome (ACS) octogenarians. METHODS The study cohort comprised 660 consecutive ACS octogenarians who underwent coronary angiography. We classified the patients into three groups according to Hcy tertiles. Kaplan-Meier method was performed for survival and major adverse cardiac events (MACE) rates. Multivariate Cox regression was performed to identify mortality predictors. Receiver operating characteristic curve analysis was performed to predict the cutoff value of Hcy for all-cause mortality. RESULTS The follow-up period was 28 (inter-quartile range: 16-38) months. Diastolic blood pressure, ratios of male, renal failure and old myocardial infarction in high plasma level Hcy (H-Hcy) group were higher than those in low (L-Hcy) and middle (M-Hcy) plasma level of Hcy groups (P<0.05). The Hcy level was positively correlated with uric acid level (r=0.211, P=0.001) and Cystatin C (Cys C) level (r=0.212, P=0.001) and negatively correlated with estimated glomerular filtration rate (r=-0.148, P=0.018). For the long-term outcomes, the cumulative survival rate of H-Hcy group was significantly lower than that of L-Hcy and M-Hcy groups (P=0.006). All-cause mortality and MACE of H-Hcy group were higher than those of L-Hcy and M-Hcy group (P=0.0001, P=0.0008). Hcy is an independent predictor for long-term all-cause mortality (odds ratio =2.26, 95% CI=1.23-4.16, P=0.023) and MACE (odds ratio =1.91, 95% CI=1.03-3.51, P=0.039). Receiver operating characteristic curve analysis indicated the predictive cutoff value of Hcy for all-cause mortality was 17.67 μmol/L (0.667, 0.681). CONCLUSION In ACS octogenarians, hyperhomocysteinemia is an important predictor for long-term all-cause mortality and MACE.