What are the effects of Vitamin B1 (Thiamine) deficiency?

From the Guidelines

Thiamine deficiency can lead to severe neurological complications, including Wernicke encephalopathy and Korsakoff syndrome, and should be treated promptly with thiamine supplementation, typically starting with 100mg intravenously three times daily for severe cases or 100mg orally daily for less severe cases, as recommended by the most recent guidelines 1. The effects of Vitamin B1 (Thiamine) deficiency can be devastating, ranging from mild symptoms such as apathy and confusion to severe neurological disorders like Wernicke-Korsakoff encephalopathy, optic neuropathy, and central pontine myelinolysis 1.

Key Considerations

• Thiamine deficiency is a major public health concern in several low- and middle-income countries, and clinical suspicion should be high in patients with malnutrition, alcoholism, and other risk factors 1.
• Early recognition and treatment of thiamine deficiency are crucial, as thiamine reserves can be depleted as early as 20 days of inadequate oral intake, and delayed treatment can lead to increased mortality 1.
• The refeeding syndrome is a particular concern in inpatients with thiamine deficiency, and prompt treatment with thiamine supplementation can help prevent this potentially life-threatening condition 1.

Treatment Recommendations

• For patients with suspected thiamine deficiency, treatment should be initiated promptly, with doses ranging from 100mg orally daily for mild cases to 500mg intravenously three times daily for severe cases, such as Wernicke encephalopathy 1.
• Maintenance therapy with 50-100mg of thiamine daily is recommended for patients with proven deficiency, and dietary sources of thiamine, such as whole grains, meat, fish, and legumes, should be incorporated into the diet for long-term prevention 1.
• In patients receiving glucose infusions, thiamine should be administered before glucose to prevent precipitating or worsening encephalopathy 1.

From the FDA Drug Label

CLINICAL PHARMACOLOGY: ... Increased levels of pyruvic acid in the blood indicate vitamin B 1 deficiency. ... Body depletion of vitamin B 1 can occur after approximately three weeks of total absence of thiamine in the diet.

The effects of Vitamin B1 (Thiamine) deficiency include:

• Increased levels of pyruvic acid in the blood
• Body depletion of vitamin B1 after approximately three weeks of total absence of thiamine in the diet 2

From the Research

Effects of Vitamin B1 (Thiamine) Deficiency

• Thiamine deficiency can lead to various health issues, including:
  • Wernicke's encephalopathy (WE), an acute and potentially life-threatening neurological disorder 3
  • Dry beriberi, characterized by neurological signs and symptoms 4
  • Wet beriberi, characterized by cardiovascular signs and symptoms 4
  • Lactic acidosis, peripheral neuropathy, ataxia, and ocular changes such as nystagmus 5
  • Confabulation and memory loss, and/or psychosis, resulting in Wernicke's Korsakoff syndrome 5
  • Congestive heart failure, peripheral neuropathy, and gastrointestinal beriberi 6
  • Intensive care unit complications, such as heart failure, delirium, critical care neuropathy, gastrointestinal dysfunction, and unexplained lactic acidosis 6
• Thiamine deficiency can occur due to various factors, including:
  • Inadequate nutrition 4, 6
  • Alcohol use disorders 4, 6
  • Increased urinary excretion and acute metabolic stress 6
  • Sepsis 6, 7
  • Surgical procedures 6
  • Malnutrition, refeeding syndrome, gastrointestinal surgery, and alcoholism 4
• Early treatment with thiamine supplementation is essential to prevent permanent neurological damage and other complications 3, 4, 7