A randomized double-blind placebo-controlled trial of intravenous thiamine for prevention of delirium following allogeneic hematopoietic stem cell transplantation

Whole blood thiamine, intravenous thiamine supplementation and delirium occurrence in the intensive care unit: retrospective cohort analyses

BACKGROUND

Thiamine di-phosphate is an essential cofactor in glucose metabolism, glutamate transformation and acetylcholinesterase activity, pathways associated with delirium occurrence. We hypothesised that a deficiency in whole blood thiamine and intravenous thiamine supplementation could impact delirium occurrence.

AIM

To establish whether a deficiency in whole blood thiamine and/or intravenous thiamine supplementation within 72 h of intensive care admission is associated with delirium occurrence.

METHOD

The first dataset was secondary analysis of a previous study in an intensive care unit in the Netherlands, reported in 2017. The second dataset contained consecutive intensive care admissions 2 years before (period 1: October 2014 to October 2016) and after (period 2: April 2017 to April 2019) routine thiamine supplementation was introduced within 72 h of admission. Delirium was defined as a positive Confusion Assessment Method-Intensive Care Unit score(s) in 24 h.

RESULTS

Analysis of the first dataset (n = 57) using logistic regression showed no relationship between delirium and sepsis or whole blood thiamine, but a significant association with age (p = 0.014). In the second dataset (n = 3074), 15.1% received IV thiamine in period 1 and 62.6% during period 2. Hierarchical regression analysis reported reduction in delirium occurrence in the second period; this did not reach statistical significance, OR = 0.81 (95% CI 0.652-1.002); p = 0.052.

CONCLUSION

No relationship was detected between whole blood thiamine and delirium occurrence on admission, at 24 and 48 h. It remains unclear whether routine intravenous thiamine supplementation during intensive care admission impacts delirium occurrence. Further prospective randomised clinical trials are needed.

Thiamine supplementation in hospitalized patients with altered mental status: does it help?

OBJECTIVE

To describe thiamine-prescribing patterns and to study the association of thiamine supplementation with clinical outcomes in hospitalized patients with altered mental status (AMS).

METHODS

We conducted a retrospective cohort study of all adult hospitalized patients with AMS with index admission in calendar year 2017. We studied the association of a) supplemental thiamine and b) timing of thiamine relative to glucose, with hospital outcomes - length of stay (LOS), 90-day readmission rates, and mortality rates - using linear, logistic, and extended Cox models, respectively. We also modeled association of supplemental thiamine on time to resolution of AMS using extended Cox models in patients admitted with AMS.

RESULTS

Of 985 patients, 178 (18%) received thiamine, including 123 (12.5%) who received thiamine before, with, or without glucose (thiamine first). We identified 365 (37%) patients who received intravenous glucose before or without thiamine (glucose first). We found that patients who received glucose first had longer LOS and higher rate of in-hospital deaths compared to those who did not. Patients who received thiamine supplementation had longer LOS compared to those who did not. There were no significant differences in other hospital outcomes or AMS resolution by discharge compared to their respective reference groups.

CONCLUSION

Although thiamine supplementation was not associated with better hospital or cognitive outcomes, we do not have enough evidence to suggest a change in current practice. Thiamine must be administered prior to glucose in hospitalized patients with AMS.

Delirium in Critical Illness Patients and the Potential Role of Thiamine Therapy in Prevention and Treatment: Findings from a Scoping Review with Implications for Evidence-Based Practice

INTRODUCTION

Thiamine is a water-soluble vitamin and is necessary for energy metabolism. Critically ill patients are at particular risk of developing thiamine deficiency and related complications. One of the complications that can occur is delirium. Delirium is a disorder that affects the body's response to treatment, length of stay in the ward, mortality, long-term cognitive impairment, and significantly increases treatment costs. In addition, studies show that delirium medication is more effective in preventing than in treating delirium. Given its low cost, availability, and minimal risk of side effects, thiamine supplementation could prove to be a relevant strategy in the prevention and treatment of delirium.

METHODS

PubMed, Cochrane Library, Ovid, and ClinicalTrials.gov databases were searched using relevant keywords that focus on the use of thiamine to prevent or treat delirium in critically ill patients.

RESULTS

Seven articles were included in the analysis.

CONCLUSION

The small number of studies and considerable heterogeneity prevent conclusions supporting the use of thiamine as an adjuvant in the prevention and treatment of delirium among critically ill patients. There is a need for high-quality, large-scale randomized clinical trials to confirm the beneficial effects of thiamine in the prevention and treatment of delirium.