Trimethylamine-N-Oxide and Precursors as Novel Potential Biomarkers for Anxiety Disorder

Background Anxiety disorder (AD) is closely related to changes in the composition of the gut microbiota, and changes in gut microbiota abundance affect the synthesis of trimethylamine N-oxide (TMAO). Objective To explore whether TMAO is related to and serves as a potential biomarker for the diagnosis of AD. Methods The concentrations of TMAO, choline, and betaine were analyzed in 60 patients with AD and 60 control individuals using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Results Compared with controls, TMAO was significantly reduced in patients with AD. Logistic regression analysis demonstrated that decreased TMAO concentrations were associated with an increased risk of AD. The multiplication of TMAO and its precursors (choline and betaine) produced the best AUC for the diagnosis of AD (AUC = 0.847; 95% CI, 0.780-0.914; P <.001). Conclusion The decrease of TMAO concentration is related to the increase of anxiety disorder. TMAO and precursors could be identified as novel potential biomarkers for the diagnosis of AD.