What is the relationship between glucose (blood sugar) and thiamine (Vitamin B1)?

From the Guidelines

Glucose should not be administered to patients at risk of thiamine deficiency without first giving thiamine, as it can precipitate Wernicke-Korsakoff syndrome. When treating patients with suspected Wernicke's encephalopathy or those at risk of thiamine deficiency, the recommended approach is to give thiamine before glucose. Key points to consider:

• Thiamine must be given before glucose in at-risk patients to prevent Wernicke-Korsakoff syndrome, as supported by the British Obesity and Metabolic Surgery Society guidelines 1.
• The dose of thiamine can vary, but for patients at risk of thiamine deficiency, oral thiamine 200–300 mg daily or intravenous thiamine may be necessary, as indicated in the guidelines 1.
• It is crucial to recognize that glucose metabolism requires thiamine as a cofactor, and in thiamine-deficient states, administering glucose without thiamine can lead to acute neurological deterioration, as discussed in the context of bariatric surgery patients 1.
• The importance of thiamine supplementation is also highlighted in other clinical contexts, such as liver disease, where patients are at risk of thiamine deficiency due to poor dietary intake, malabsorption, or increased metabolic requirements 1.
• For pediatric patients on parenteral nutrition, specific recommendations for thiamine intake are provided, emphasizing the need for adequate thiamine supply to prevent deficiency and related complications 1.

From the FDA Drug Label

Clinical Pharmacology ... Its role in carbohydrate metabolism is the decarboxylation of pyruvic acid in the blood and -ketoacids to acetaldehyde and carbon dioxide. Increased levels of pyruvic acid in the blood indicate vitamin B1 deficiency. The requirement for thiamine is greater when the carbohydrate content of the diet is raised

• Thiamine plays a crucial role in carbohydrate metabolism, specifically in the decarboxylation of pyruvic acid in the blood.
• Pyruvic acid is a product of glucose metabolism, and increased levels of pyruvic acid in the blood can indicate thiamine deficiency.
• The requirement for thiamine is greater when the carbohydrate content of the diet is raised, suggesting a link between glucose intake and thiamine needs 2.

From the Research

Relationship Between Glucose and Thiamine

• The relationship between glucose and thiamine is crucial in preventing Wernicke encephalopathy, particularly in hypoglycemic patients 3.
• Thiamine deficiency can lead to Wernicke encephalopathy, and administering glucose without thiamine supplementation may exacerbate the condition 3.
• However, there is no conclusive evidence to support the idea that glucose supplementation should be delayed in hypoglycemic patients to prevent Wernicke encephalopathy 3.
• Instead, prompt thiamine supplementation after or concurrent with glucose administration is recommended to prevent Wernicke encephalopathy 3.

Glucose Monitoring and Thiamine

• Continuous glucose monitoring (CGM) can provide real-time information about glucose concentration, direction, and rate of change, which may be beneficial in managing dysglycemia in hospital settings 4, 5.
• CGM may have an advantage over point-of-care testing in reducing the incidence of severe hypoglycemia in acute care 4.
• However, the use of CGM in hospital settings is not without barriers, including regulatory, behavioral, logistical, technical, staffing, and systemic issues 6.

Clinical Implications

• The administration of glucose and thiamine should be carefully considered in hypoglycemic patients to prevent Wernicke encephalopathy 3.
• CGM may be a useful tool in managing glucose levels in critically ill patients, but its accuracy and safety need to be further evaluated 7, 5.
• Further research is needed to determine the optimal approach to glucose and thiamine administration in various clinical settings 3, 4, 6, 5.