Elevated plasma total homocysteine levels increased the risk for dementia in the elderly.

A s s e s s m e n t o f r i s k f a c t o r s Baseline data were collected on the plasma total homocysteine level. Analyses were adjusted for baseline age; sex; apolipoprotein E genotype (93% of participants); plasma levels of folate (98% of participants), vitamin B12 (85% of participants), and vitamin B6 (92% of participants); educational status; history of stroke; cigarette smoking; alcohol intake; diabetes mellitus; systolic blood pressure; and body mass index.