Delirium is an acute disturbance of consciousness with reduced ability to focus, sustain, or shift attention. It is associated with prolonged hospital stays, increased mortality rates, and cognitive dysfunction post-delirium. Thiamine and vitamin B12 deficiencies are potential etiologies of delirium. Despite well-established roles in cognitive function, the extent to which these micronutrients are being investigated as part of a delirium workup and treatment plan for hospitalist medicine patients at Vancouver General Hospital (VGH) is unknown.

To determine: 1) the prevalence of delirium as identified by physicians across the three hospitalist medicine units at VGH, and of those: 2) the number of patients who received thiamine supplementation; and, 3) the number of patients who received vitamin B12 supplementation and/or laboratory investigations of serum vitamin B12 levels.

A retrospective chart review of 199 patients admitted to VGH hospitalist medicine units (L7A, L7C, L8A) from January 1 to 31, 2019 was conducted. Descriptive statistics were used to analyze data. Results: 82 patients (41.6%) presented with delirium. Among these patients, 19.5% (n=16) received thiamine supplementation, of which 25% (n=4) were for treatment of alcohol withdrawal and 75% (n=12) had no documented reason. 9.8% (n=8) of patients with delirium received vitamin B12 supplementation, of which 12.5% (n=1) was for delirium workup. 56.1% (n=46) underwent investigations of serum vitamin B12 levels.

This study indicates that despite a high prevalence of delirium within VGH hospitalist medicine wards, delirium workups do not routinely investigate thiamine or vitamin B12 deficiencies as potential causes.

This study suggests the connection between nutritional deficiencies and delirium may be underrecognized during workup and treatment plans for delirium. Dietitians may play a key role in advocating for awareness on this topic, and identifying and treating nutritional deficiencies related to delirium.