Clinical Characteristics and Outcomes Associated With High-Dose Intravenous Thiamine Administration in Patients With Encephalopathy

Background: Wernicke encephalopathy is a common neuropsychiatric syndrome due to thiamine deficiency. There is no consensus regarding thiamine dosing when Wernicke encephalopathy is suspected. A longstanding dosing strategy for Wernicke encephalopathy is 100mg daily, yet updated clinical guidelines suggest using high-dose intravenous (HDIV) thiamine.

Objective: To describe thiamine prescribing practices at a large, public academic hospital and investigate clinical characteristics and outcomes associated with HDIV thiamine in patients with encephalopathy who received IV thiamine.

Methods: Electronic medical records of hospitalized patients who received thiamine between 4/4/2014 and 11/1/2015 were reviewed. Chi-square tests, Wilcoxon Rank Sum tests, and logistic regression were used to compare clinical variables in patients with encephalopathy who received HDIV thiamine (≥ 200mg twice daily) vs lower doses of IV thiamine.

Results: Among the total of 5236 thiamine orders, 29% (n = 1531) were IV; 10% (n = 150) of IV orders met HDIV criteria. In patients with encephalopathy who received IV thiamine (n = 432), HDIV thiamine was administered to 20% (n = 86) and only 2.1% (n = 9) received dosing consistent with Royal College of Physicians guidelines. In bivariable analyses, HDIV thiamine was associated with surgical services (p = 0.001), psychiatric consultation (p < 0.001), and decreased mortality (p = 0.004). In multivariable models, the association between HDIV thiamine and decreased in-hospital mortality did not meet statistical significance (p = 0.061).

Conclusions: In a large, public academic hospital, guideline-concordant thiamine supplementation is rare and HDIV thiamine is infrequently prescribed to patients with encephalopathy. Further studies are needed to confirm the possible benefits of HDIV thiamine for patients with suspected thiamine-deficient encephalopathy.