The correlation between trimethylamine N-oxide, lipoprotein ratios, and conventional lipid parameters in patients with unstable angina pectoris

PURPOSE: Trimethylamine N-oxide (TMAO) is recently the main risk factor for coronary heart disease (CHD). Plasma lipid levels are conventionally used to predict coronary risk, but the correlation between TMAO and plasma lipid levels in unstable angina pectoris (UAP) was unclear. Our objective was to compare the plasma level of TMAO to lipoprotein ratios and conventional lipid parameters in UAP patients. METHODS: A total of 114 control participants and 184 UAP patients were enrolled. Demographic characteristics were collected. Plasma levels of TMAO and lipid in all patients were measured and analyzed. The receiver operating characteristic analysis (ROC), univariate, and multivariate logistic regression analyses were carried out to examine the relationship between TMAO, lipoprotein ratios, conventional lipid parameters, and UAP. RESULTS: The plasma levels of TMAO were remarkably increased in UAP patients (3.28 +/- 1.97 microM) compared with control participants (1.52 +/- 0.59 microM, P < 0.01). TMAO was significantly correlated with lipid levels in UAP patients. The ROC, univariate and multivariate logistic regression analysis both showed that the TMAO significantly increased the risk for occurrence of UAP. CONCLUSIONS: Our data indicate that the TMAO is superior to lipoprotein ratios and conventional lipid parameters in predicting occurrence of UAP.