Association of cognitive impairment with plasma levels of folate, vitamin B12 and homocysteine in the elderly.

BACKGROUND: Alterations in folate, vitamin B12 and homocysteine plasma levels have been associated with aging, neuronal development and cognitive impairment. The aim of this study was to investigate the relationship between plasma folate, vitamin B12 and homocysteine and cognitive function in the elderly. PATIENTS AND METHODS: Elderly individuals over 60 years of age living in the community, were screened with the Mini-Mental State Examination. The study population was divided into two groups: (a) 37 subjects with dementia; and (b) 33 healthy controls. Blood samples were analyzed with the use of ELISA, and the results were statistically evaluated at p < 0.05 level of significance. RESULTS: Group a had significantly lower levels of folate and vitamin B12 than group b. Homocysteine was significantly higher in demented individuals than in controls (p < 0.01). CONCLUSION: Lower levels of plasma folate and/or vitamin B12 and higher levels of plasma homocysteine are associated with cognitive impairment in elderly individuals.