I read with interest the article by Morris et al.1 Reviewing the cognitive tests administered, it appears that memory was preserved with both dietary and supplementary vitamin E. Some of the subjects were probably experiencing mild cognitive impairment, which is characterized by memory impairment with preservation of general cognitive and functional abilities and an absence of dementia.2 Neuropathologic studies have revealed that such individuals almost always have features of Alzheimer disease3 and that more impaired individuals nearly always progress to greater dementia severity within 10 years. It would seem that vitamin E is able to delay the progression of mild cognitive impairment to dementia. Because mild cognitive impairment generally represents early-stage Alzheimer disease, the results of the study indicate that vitamin E treatment affects the course of this disease.
Steven R. Brenner. Vitamin E Treatment Affects the Progression of Mild Cognitive Impairment to Dementia. Arch Neurol. 2003;60(2):292. doi:10.1001/archneur.60.2.292-a