Trimethylamine N-Oxide and mortality in hemodialysis patients: like a mystery.

Dear Sir, I have read with great interest the paper entitled 'Association of trimethylamine I N i -Oxide with cardiovascular and all-cause mortality in hemodialysis patients' by Zhang et al. [[1]]. TMAO was measured by liquid chromatography/mass spectrometry using TMAO-D9 as the internal standard. Plasma TMAO levels in HD patients reflect the net effect of TMAO production and clearance. [Extracted from the article]