Abstract | BACKGROUND AND PURPOSE: A higher plasma concentration of total homocysteine (tHcy) is associated with a greater risk of cardiovascular events. Previous studies, largely in younger individuals, have shown that B vitamins lowered tHcy by substantial amounts and that this effect is greater in people with higher tHcy and lower folate levels. METHODS: We undertook a 2-year, double-blind, placebo-controlled, randomized trial in 299 men aged > or =75 years, comparing treatment with a daily tablet containing 2 mg of folate, 25 mg of B6, and 400 microg of B12 or placebo. The study groups were balanced regarding age (mean+/-SD, 78.9+/-2.8 years), B vitamins, and tHcy at baseline. RESULTS: Among the 13% with B12 deficiency, the difference in mean changes in treatment and control groups for tHcy was 6.74 micromol/L (95% CI, 3.94 to 9.55 micromol/L) compared with 2.88 micromol/L (95% CI, 0.07 to 5.69 micromol/L) for all others. Among the 20% with hyperhomocysteinaemia, the difference between mean changes in treatment and control groups for men with high plasma tHcy compared with the rest of the group was 2.8 micromol/L (95% CI, 0.6 to 4.9 micromol/L). Baseline vitamin B12, serum folate, and tHcy were significantly associated with changes in plasma tHcy at follow-up (r=0.252, r=0.522, and r=-0.903, respectively; P=0.003, <0.001, and <0.001, respectively) in the vitamin group. CONCLUSIONS: The tHcy-lowering effect of B vitamins was maximal in those who had low B12 or high tHcy levels. Community-dwelling older men, who are likely to be deficient in B12 or have hyperhomocysteinemia, may be most likely to benefit from treatment with B vitamins.
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Authors | Leon Flicker, Samuel D Vasikaran, Jenny Thomas, John M Acres, Paul Norman, Konrad Jamrozik, Graeme J Hankey, Osvaldo P Almeida |
Journal | Stroke
(Stroke)
Vol. 37
Issue 2
Pg. 547-9
(Feb 2006)
ISSN: 1524-4628 [Electronic] United States |
PMID | 16373648
(Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
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Chemical References |
- Placebos
- Homocysteine
- Vitamin B Complex
- Folic Acid
- Vitamin B 12
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Topics |
- Aged
- Dietary Supplements
- Double-Blind Method
- Folic Acid
(pharmacology)
- Homocysteine
(blood)
- Humans
- Hyperhomocysteinemia
(blood, therapy)
- Male
- Placebos
- Time Factors
- Treatment Outcome
- Vitamin B 12
(pharmacology)
- Vitamin B 12 Deficiency
(blood, therapy)
- Vitamin B Complex
(pharmacology)
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