Characteristic features of folate-deficient neurological diseases in the elderly

Background:  Folic acid (folate) deficiency causes neurological disorders in aged people, the characteristic features of which were examined.
Methods:  Serum folate levels were determined in 343 neurological patients by chemiluminescence. We found 36 folate-deficient patients (10.5%) who were divided into elderly ≥ 65 years old (12 cases) and younger group, < 65 years old (24 cases), and were administered folate (15 mg/day) for 60 days.
Results:   Serum folate levels were not different between the elderly and younger group, while folate levels were lower in elderly females than elderly males. Neuropathy was more frequent in elderly male than elderly female patients. Elderly neurological patients with neuropathy more readily responded to folate supplementation than those without neuropathy. Folate-deficient patients with dementia were older than those without dementia, although nine younger patients had dementia and four of nine cases showed frontal dementia. Anemia or female sex was more frequent and neuropathy was less frequent among elderly patients with central nervous system involvement. Serum folate levels were lower in elderly anemic than nonanemic patients. Tube feeding was more frequent in elderly folate-deficient neurological patients than in younger ones. Folate therapy was less effective in elderly patients with dementia, although three cases improved. Elderly folate-deficient patients treated with tube feeding did not respond to the folate supplement.
Conclusion:   Folate deficiency was not rare among aged neurological patients, and its features were different from younger patients. Since folate-deficient neuroencephalopathies are responsive to folate supplementation in the elderly, the examination of elderly patients' serum folate level is valuable.