INTRODUCTION: Familial isolated deficiency of vitamin E (VED or AVED; MIM #277460) is a progressive neurodegenerative disorder resembling Friedreich ataxia. It is caused by the deficiency of α-tocopherol transfer protein that prevents patients from retaining vitamin E. Oral vitamin E supplements are an accepted treatment, but detailed dosage recommendations and reports on long-term therapeutic results are scarce.
METHODS: The first patient with VED was discovered at our institution at the age of 12 years and has since been followed with clinical, neurophysiological, neuroradiological, and biochemical investigations to his present age of 52 years. For the last 36 years, the patient has scrupulously followed a custom-made high-dose vitamin E supplement regimen that we devised on the basis of studies of his metabolism of vitamin E.
RESULTS: Over the long period of observation, the patient has remained in good general health and has not shown progression of neurological symptoms and signs. His vitamin E plasma levels were always moderately above the normal range. During short interruptions of vitamin E supplements, vitamin E levels fell rapidly, even after years of massive supplementation.
DISCUSSION: In this VED patient, a specified and carefully controlled high-dose vitamin E therapy has prevented any recognizable progression of the neurodegenerative process over more than 3 decades of observation.