Supplementary Material for: Thiamine Substitution in Alcohol Use Disorder: A Narrative Review of Medical Guidelines

Aims: Patients with alcohol use disorder (AUD) frequently suffer from cognitive deficits ranging from mild symptoms to most severe forms. Wernicke encephalopathy (WE), caused by thiamine deficiency, is a potentially fatal syndrome characterized by the clinical triad of ophthalmoplegia, ataxia, and confusion. WE frequently presents in patients with AUD and, if left untreated, can progress to Wernicke-Korsakoff syndrome, which constitutes severe anterograde amnesia, confabulation, and behavioral abnormalities. Due to oftentimes indistinct clinical presentation, WE remains undiagnosed in up to 80% of cases. We conducted a review of current treatment guidelines for AUD in order to identify recommendations for the use of thiamine. Methods: Three different keyword combinations (“alcohol treatment guideline,” “alcohol withdrawal guideline,” and “alcohol treatment recommendation”) were entered in PubMed and Scopus, additional guidelines were searched screening the online sites of the respective agencies or societies. In total, 14 guidelines were included. Results: Thiamine was mentioned in all but one of the reviewed publications. Specifications on application modalities and indications varied considerably. While the majority of reviewed guidelines recommended parenteral thiamine only for patients at high risk for WE, some gave no information regarding the application form or dosage. Conclusion: Substitution of parenteral thiamine in individuals with suspected WE is a well-established treatment regimen. However, suggestions according to guidelines vary widely. Furthermore, hardly any evidence-based recommendations exist on a more general use of thiamine as a preventative intervention in individuals with AUD. Further research is of utmost importance to raise awareness for this potentially undervalued problem.