A clinical trial led by Paul S. Aisen, M.D., professor of neurosciences at the University of California, San Diego School of Medicine, showed that high-dose vitamin B supplements did not slow the rate of cognitive decline in patients with mild to moderate Alzheimer disease.
The study will be published in the October 15 issue of the Journal of the American Medical Association (JAMA).
Aisen is director of the Alzheimer's Disease Cooperative Study (ADCS), a multi-center network spanning the United States and Canada, which conducted the clinical trial to determine if reduction of an amino acid called homocysteine would reduce the risk of Alzheimer's disease or slow its progression. Homocysteine is known to be involved in neurological disease, including Alzheimer's, and its metabolism is affected by B vitamins. Therefore, it was thought that B vitamin supplements might offer a new therapeutic approach in treating Alzheimer' disease.
"Prior studies using B vitamin supplementation to reduce homocysteine levels in patients with Alzheimer's weren't large enough, or of long enough duration to effectively assess their impact on cognitive decline," said Aisen. "This study of several hundred individuals over the course of 18 months showed no impact on cognition, although it resulted in lower levels of homocysteine in these patients."