MilliporeSigma
  • B vitamin therapy for homocysteine: renal function and vitamin B12 determine cardiovascular outcomes.

B vitamin therapy for homocysteine: renal function and vitamin B12 determine cardiovascular outcomes.

Clinical chemistry and laboratory medicine (2013-03-02)
John David Spence
ABSTRACT

Therapy to lower homocysteine with B vitamins does reduce the risk of stroke, if not myocardial infarction. The apparent lack of efficacy of vitamin therapy in most of the large clinical trials was probably determined by the failure to take account of the metabolic deficiency of vitamin B12, which is very common and often missed, and by the failure to take account of impaired renal function. Metabolic B12 deficiency is present in 20% of people over 65 years of age, and in 30% of vascular patients above 70 years, so higher doses of B12 are needed in elderly patients. However, high-dose cyanocobalamin leads to accumulation of cyanide in patients with renal failure. B vitamin therapy is beneficial in patients with good renal function, but harmful in patients with significantly impaired renal function (a glomerular filtration rate <50). It seems likely that in patients with renal impairment, methylcobalamin should be used instead cyanocobalamin.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Methylcobalamin, vitamin B12 analog