By Marcello Cherchi, MD PhD
Vitamin B1, also called thiamine, is usually obtained in the diet from animal products (fish, meat) and from whole grains. In industrialized countries many foods are fortified by the addition of vitamin B1. Vitamin B1 functions as a cofactor for enzymes involved in the metabolism of carbohydrates and branched-chain amino acids.
Vitamin B1 deficiency can occur due to dietary deprivation such as starvation and alcoholism.
In severe cases, vitamin B1 deficiency can present as Wernicke-Korsakoff syndrome, which involves amnesia (and thus confabulation), psychosis, ataxia and ocular motor abnormalities.
The ocular motor abnormalities may be among the first manifestations of incipient vitamin B1 deficiency, and thus are important to recognize as the possible harbinger of florid Wernicke-Korsakoff syndrome.
The eye movement abnormalities described in association with vitamin B1 deficiency include:
- Ophthalmoparesis (Kattah 2017)
- Symmetric vestibular weakness, manifesting as decreased vestibulo-ocular reflex gain (Kattah, Dhanani et al. 2013, Kattah 2017)
- Horizontal gaze-evoked nystagmus (Kattah, Dhanani et al. 2013, Kattah 2020)
Treatment is parenteral administration of vitamin B1, followed by oral supplementation.
References
Kattah JC (2017) The Spectrum of Vestibular and Ocular Motor Abnormalities in Thiamine Deficiency. Curr Neurol Neurosci Rep 17: 40. doi: 10.1007/s11910-017-0747-9
Kattah JC (2020) Early Signs of Thiamine Deficiency: A Case Report. Ann Intern Med 173: 72-73. doi: 10.7326/L19-0836
Kattah JC, Dhanani SS, Pula JH, Mantokoudis G, Tehrani ASS, Toker DEN (2013) Vestibular signs of thiamine deficiency during the early phase of suspected Wernicke encephalopathy. Neurol Clin Pract 3: 460-468. doi: 10.1212/01.CPJ.0000435749.32868.91
