Trial in elderly veterans shows promise for those in early stages
The sagging reputation of vitamin E as a disease fighter could be on the upswing. The antioxidant, which has shown inconsistent results in studies, can slow functional decline in elderly people with mild to moderate Alzheimer’s disease, a new study suggests. Patients randomly assigned to get the vitamin in high daily doses didn’t lose their ability to carry out basic daily activities as rapidly as those getting a placebo, researchers report in the Jan. 1 JAMA.
“This shows a modest but potentially important benefit,” says Denis Evans, an internist at Rush University Medical Center in Chicago. “Surely one would like a revolutionary gain against this grim and really common disease. But chewing away at it by bits and pieces — and that’s what’s happening here — is very good news.”
Although vitamin E is important for many processes in the body, it has a shaky record as a supplement. In recent years, it has failed to show a benefit against cardiovascular disease and other ailments. The big blow came in a 2005 review by researchers at Johns Hopkins University and elsewhere who analyzed 11 trials in which some participants were assigned to take high doses of vitamin E. Those people collectively were more likely to die during the subsequent years than those who didn’t take it.
But only one of those trials specifically involved Alzheimer’s patients, and that trial suggested that vitamin E might improve survival. Psychiatrist Maurice Dysken of the Minneapolis Veterans’ Affairs Health Care System also notes that in that trial, vitamin E seemed to slow functional decline in the patients, who had moderately severe Alzheimer’s disease.
The vitamin hadn’t been tested in a randomized trial of people with mild to moderate Alzheimer’s disease, so Dysken and his colleagues assigned 613 Alzheimer’s patients to get one of four treatments: 2,000 international units daily of vitamin E, 20 milligrams the drug memantine, both or a placebo. All but one of the patients were already on a drug called an acetylcholinesterase inhibitor, with most taking donepezil (Aricept) or galantamine (Razadyne). The participants were veterans, and nearly all were men.
After an average follow-up of 2.3 years, no mortality difference emerged between the groups. But patients getting just vitamin E retained the ability to carry out daily activities longer than those getting the placebo. Specifically, they reached new low points in functionality several months later than those taking a placebo did, on average.
The participants getting memantine didn’t fare any better on functionality than those getting dummy pills. And neither vitamin E nor memantine offered any delay in cognitive or memory loss compared with the placebo group.
Participants’ caregivers, typically a spouse or an adult child, logged the number of hours needed to care for the Alzheimer’s patients, which was about three hours a day at the study outset. Their caregiving time rose by 3.4 hours a day in the vitamin E group during the study, but by at least 5 hours a day in the other three groups.
While that difference could have been due to chance, Dysken says, it suggests that the modest benefit of vitamin E could help families as well as patients. But he cautions that the 2,000 IU of daily vitamin E used in this trial is much higher than the recommended intake for adults, which is only 22.4 IU in most cases. Caregivers should consult a doctor before giving the vitamin to a patient, he says.
Editor's Note: This story was updated January 24, 2014, to correct the number of high-dose trials analyzed in the 2005 review.
M.W. Dyskenet al. Effect of vitamin E and memantine on functional decline in Alzheimer disease: The TEAM-AD VA Cooperative Randomized Trial.JAMA. Vol. 311, Jan. 1, 2014, p. 33. doi: 10.1001/jama.2013.282834.
E. R. Miller III et al. Meta-Analysis: High-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine. Vol. 142, Jan. 4, 2005, p. 37. doi: 10.7326/0003-4819-142-1-200501040-00110.
M. Sano et al. A controlled trial of selegiline, alpha-tocopherol, or both as treatment for Alzheimer's disease. New England Journal of Medicine. Vol. 336, April 24, 1997, p. 1212. doi: 10.1056/NEJM199704243361704.
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