Association of Circulating Trimethylamine-N Oxide With Malnutrition and the Risk of Coronary Artery Disease in Patients With Maintenance Hemodialysis

Abstract

Malnutrition is a serious complication frequently observed in dialysis patients. Therefore, nutrition status evaluation and the early identification of malnutrition are clinically important. Trimethylamine N-oxide (TMAO) is reportedly associated with deteriorating metabolic profiles and cardiovascular diseases. The aim of our study was to investigate correlations between circulating TMAO levels and malnutrition and the risk of major adverse cardiovascular events in patients on maintenance hemodialysis. This retrospective observational study involved 228 subjects. Fasting plasma TMAO levels were detected using liquid chromatography-tandem mass spectrometry. TMAO levels were significantly elevated in patients with malnutrition (8728.78±704.12ng/mL) when compared with those without (6532.1±570.41ng/mL, P<.01). TMAO levels were positively correlated with Subjective Global Assessment scores (ρ=0.56, P=.02) and were independent risk factors for malnutrition after adjustment for multiple traditional risk factors (odds ratio=2.07, 95% confidence interval: 1.41-3.62, P<.01). Furthermore, TMAO levels were good predictors of major adverse cardiovascular events in a 2-year follow-up period (area under the curve=0.68, P<.01) and accuracy was increased to 74% when TMAO levels were combined with Subjective Global Assessment scores (area under the curve=0.74, P=.02). Elevated TMAO levels were independently associated with a risk of malnutrition and cardiovascular disease, and could be a useful predictive biomarker for risk stratification and cardiovascular disease management for patients on dialysis.