Results released today of a study published in the New England Journal of Medicine indicated that large doses of vitamin E may delay the time at which late-stage Alzheimer's patients must be institutionalized because of the loss of "daily living" skills such as feeding, grooming and continence. Patients who were given vitamin E took significantly longer (hundreds of days) to reach any of four major milestones-death, institutionalization, loss of ability to perform normal activities or progression to severe dementia-than those given a placebo. The effects with selegiline, another antioxidant, were also significant but less marked.
The vitamin E levels in the study were quite high, about six times the recommended daily dosage of 30 international units. Patients taking vitamin E had significantly more falls and fainting spells than those taking placebos. And unlike results from studies of women with Alzheimer's who were given estrogen replacement therapy, there was no improvement in victims’ memory and comprehension. The next step is a similar study on patients in earlier stages of Alzheimer's progression, to see if the onset of Alzheimer's debilitating cognitive symptoms can be delayed.
The drug selegiline, a monoamine oxidase-B inhibitor (administered in this study as the commercial drug Eldepryl), has already been studied as a neuroprotective anti-oxidant for Alzheimer's. Selegiline suppresses hydroxyl radical formation, stimulates biosynthesis of interleukin-1 beta and interleukin-6 and protects the substantia nigra in aged rats (see further reading).—June Kinoshita
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