High levels of TMAO have been associated with an increased risk of heart disease.1
The TMAO test may be used as (1) an aid in the assessment of risk for cardiovascular disease (CVD), independent of established risk factors, (2) an aid in the determination of altered gut microbiome (gut dysbiosis) in individuals who may benefit from intensive dietary intervention, and (3) a monitor therapy aimed at reducing TMAO concentrations.
This test was developed and its performance characteristics determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration.
TMAO is a dietary metabolite produced by a pathway involving gut microbiota. TMAO concentrations increase in the blood after ingestion of dietary choline and L-carnitine, which are abundant in meat, eggs, liver, and wheat germ and energy drinks. Choline and L-carnitine are metabolized in the gut by microbiota to form trimethylamine (TMA), which is subsequently oxidized in the liver into TMAO by flavin monooxygenases (FMOs). TMAO concentrations have been shown to be reduced in animals and humans treated with broad-spectrum oral antibiotics confirming the requirement for gut bacteria in the formation of TMA and TMAO.2-6 TMAO has been hypothesized to promote atherosclerosis by upregulating macro-phage scavenger receptor activity and downregulating bile acid synthesis which together reduce reverse cholesterol transport.2-6
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