Diet-Derived Trimethylamine N-Oxide (TMAO) Pathway Disruption in Patients with Concurrent Alcohol Use Disorder and Smokers Persists After Alcohol Detoxification

Abstract

Diet-Derived Trimethylamine N-Oxide (TMAO) Pathway Disruption in Patients with Concurrent Alcohol Use Disorder and Smokers Persists After Alcohol Detoxification

Abstract

Background and Purpose: Trimethylamine N-oxide (TMAO), a gut-microbiota-derived metabolite, is associated with cardiometabolic diseases, and therapeutic strategies targeting TMAO reduction are gaining interest for disease management. This study aimed to compare serum TMAO levels in patients with alcohol use disorder (AUD) and smokers versus healthy controls, and to assess changes following medically supervised alcohol detoxification. Method: Demographic data, biochemical parameters, and serum TMAO levels were analyzed. These parameters were quantified in healthy controls and patients with AUD and smokers before and after alcohol detoxification. Results: The study included thirty-four healthy controls (six females and 28 males) and thirty-three patients (five females and 28 males) with AUD and smokers. At baseline, patients demonstrated significantly lower TMAO levels but higher levels of ferritin, CRP, AST, ALT, GGT, and MCV compared to healthy controls. Following detoxification, patients exhibited a further decrease in TMAO levels (p=0.024), alongside significant improvements in hepatic enzymes (AST and GGT) and ferritin levels (p<0.001). Conclusions: These findings provide novel evidence that AUD combined with smoking is associated with markedly reduced TMAO levels, and that detoxification treatment leads to a further decline. This suppression likely reflects underlying gut dysbiosis, impaired hepatic function, and malnutrition, and persists even after detoxification.

Keywords

• Alcoholism
• Dysbiosis
• Inflammation
• Malnutrition
• Smoking

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