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Advanced age as a risk factor for folate-associated functional cobalamin deficiency.
1Section of Palliative Care, Department of Medicine, School of Medicine, Yale University, New Haven, CT 06520, USA. lawrence.solomon@yale.edu
Journal of the American Geriatrics Society
|March 26, 2013
Summary
High serum folate levels can increase methylmalonic acid (MMA) in older adults with low cobalamin, an effect reversed by cobalamin therapy. This suggests caution with folic acid supplements in the elderly.
Area of Science:
- Gerontology
- Nutritional Biochemistry
- Clinical Medicine
Background:
- Elevated serum folate levels may impact vitamin B12 metabolism.
- Understanding the interplay between folate and cobalamin is crucial for managing age-related metabolic changes.
Purpose of the Study:
- To investigate the association between high serum folate levels and metabolite changes (methylmalonic acid and homocysteine) in elderly individuals with normal cobalamin levels.
Main Methods:
- A case series involving 233 ambulatory adults without diabetes, normal renal function, and normal cobalamin levels.
- Measurements included serum cobalamin, serum folate, methylmalonic acid (MMA), and homocysteine.
Main Results:
- Older adults (≥60) with low-normal cobalamin (201-300 pg/mL) and high serum folate (>20 ng/mL) exhibited higher MMA and lower homocysteine levels.
- This association was age-dependent and reversed by cobalamin therapy, with MMA potentially being neurotoxic.
Conclusions:
- High serum folate levels are linked to increased MMA in elderly individuals with low-normal cobalamin, indicating a potential threshold effect.
- Cobalamin therapy effectively normalized MMA and homocysteine levels.
- Caution is advised regarding folic acid supplementation in the elderly due to potential adverse effects on MMA levels.
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