Correlations between folate, B-12, homocysteine levels, and radiological markers of neuropathology in elderly post-stroke patients

Objective: To investigate serum levels of folate, B-12, and total homocysteine (tHcy) in elderly post-stroke patients, and the possible correlations with radiological markers of neuropathology. Design: Cross-sectional study. Setting: Department of Neurology, Cardinal Tien Hospital. Subjects: Eighty-nine elderly post-stroke patients were enrolled for dietary assessment and blood tests. Neuroradiological assessment was done in 62 of these patients. Main Outcome Measures: Dietary folate and vitamin B-12 intakes were evaluated by a 24-h recall system using a semi-quantitative questionnaire. Circulating levels of folate, B-12, and tHcy were measured. Magnetic resonance imaging (MRI) or computed tomography (CT) was used for evaluation of brain lesions including infarction and atrophy. Results: Mean folate and B-12 intakes of these post-stroke patients were 69% and 261 % of the recommended dietary allowances (RDA), respectively. Inadequate folate levels, defined as serum folate < 6 ng/mL, was noted in 68% of these patients. Hyperhomocysteinemia levels (tHcy >= 15 mu mol/L) were observed in 48%. According to tertiles of serum tHcy and folate levels, the rate of brain atrophy, but not brain infarctions, are significantly associated with elevated tHcy (P = 0.0126) and decreased folate levels (P = 0.0273). After adjustments for age, sex, disease status, brain infarctions and carotid stenosis, the odds ratio of brain atrophy was 9.8 (95% CI: 1.7-56.4, P = 0.0101) in the hyperhomocysteinemia group and 9.6 (95% CI: 1.1-81.3, P = 0.0377) in the low folate group (serum folate < 3.0 ng/mL) compared with the group with normal tHcy and folate levels. No significant association was noted between vitamin B-12 levels and brain lesions. Conclusions: Our data shows that folate deficiency and hyperhomocysteinemia are prevalent in elderly post-stroke patients. These two conditions are strongly and independently associated with the development of brain atrophy.