Findings from a new study, published in JAMA Neurology , suggest antioxidant supplements are not useful in preventing dementia.
Oxidative stress is an established dementia pathway, but it is unknown if the use of antioxidant supplements can prevent dementia. The Prevention of Alzheimer’s Disease by Vitamin E and Selenium (PREADViSE) clinical trial initially enrolled 7,540 older men who used the supplements for an average of about five years and a subset of 3,786 men who agreed to be observed longer. The men received either vitamin E, selenium, both or a placebo.
The authors found the incidence of dementia (325 of 7,338 men [4.4 per cent]) was not different among the four study groups.
The authors acknowledged there were limitations in the study including losing about half of the participants to long-term follow-up during the transition from a randomised clinical trial to a cohort study. Publicity about the negative effect of supplements also may have played a role, they said.
The authors concluded: “The supplemental use of vitamin E and selenium did not forestall dementia and are not recommended as preventive agents.”
The PREADViSE trial is a member of the first generation of Alzheimer’s disease prevention trials, all of which failed to meet their primary goal.