A population-based, prospective study of elderly British individuals shows that risk of memory loss increases over time with increasing levels of total blood homocysteine and decreasing folate levels.
Homocysteine is an amino acid in the blood. Too much of it ups the risk for coronary heart disease, stroke and fatty deposits in peripheral arteries. High circulating levels of homocysteine, especially with advancing age, have also been associated with cognitive impairment. Homocysteine levels in the blood are strongly influenced by diet and genetics.
Folic acid and other B vitamins help break down homocysteine in the body.
Dr. Eha Nurk and colleagues at the University of Oxford examined more than 2,100 subjects aged 65 to 67 years at baseline who lived in the community. The investigators measured total plasma homocysteine levels, folate, vitamin B12 and memory at baseline between 1992 and 1993 and then again six years later.
They discovered that subjects showing a memory deficit on a standard test had higher total plasma homocysteine and lower folate levels at follow-up than subjects who did not.
“The risk of memory deficit increased according to quintiles of total homocysteine both at baseline and at follow-up,” the authors report in the Annals of Neurology.
The researchers note that clinical trials on memory loss with total homocysteine-reducing therapies and vitamin supplements should be forthcoming and yield promising results.