Lowering homocysteine with B vitamins has no effect on blood pressure in older adults.
An elevated circulating homocysteine concentration is associated with the risk of cardiovascular disease. The mechanism by which an elevated homocysteine increases cardiovascular risk is unclear but may be mediated in part by elevating blood pressure. It is well established that supplements containing folate, vitamins B-12, and B-6 lower homocysteine concentrations. However, the effect of homocysteine-lowering vitamins on blood pressure has not been well studied. We sought to determine whether lowering homocysteine with B vitamins lowers blood pressure in healthy older people with elevated homocysteine concentrations. Two hundred seventy-six healthy older participants (> or = 65 y) with a homocysteine > or = 13 micromol/L were randomized to receive a daily supplement containing folate (1 mg), vitamin B-12 (500 microg), and vitamin B-6 (10 mg), or a placebo, for 2 y. Plasma homocysteine was lower in the Vitamins group than the Placebo group at both 1 [-4.3 micromol/L (95% CI; -4.9, -3.7)] and 2 y [-4.4 micromol/L (95% CI: -5.3, -3.6)]. Systolic and diastolic blood pressures as well as pulse pressure in the Vitamins group did not differ from the Placebo group over the duration of the trial. The mean differences in blood pressures, adjusted for baseline values, did not exceed 1 mm Hg. Supplemental B-vitamins lowered plasma homocysteine but had no effect on blood pressure in older people with elevated baseline homocysteine concentrations.
McMahon
Jennifer A
JA
Department of Human Nutrition, University of Otago, Dunedin 9001, New Zealand.
Skeaff
C Murray
CM
Williams
Sheila M
SM
Green
Timothy J
TJ
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D003971:Diastole; D004338:Drug Combinations; D005260:Female; D005492:Folic Acid / Q000494:pharmacology; D006710:Homocysteine / Q000037:antagonists & inhibitors* / Q000097:blood*; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D013599:Systole; D014805:Vitamin B 12 / Q000494:pharmacology; D025101:Vitamin B 6 / Q000494:pharmacology; D014803:Vitamin B Complex / Q000494:pharmacology*
D004338:Drug Combinations; D006710:Homocysteine; D014803:Vitamin B Complex; D025101:Vitamin B 6; D005492:Folic Acid; D014805:Vitamin B 12