Randomized clinical trial of folate supplementation in patients with peripheral arterial disease.
BACKGROUND
The aim was to determine whether folate supplementation improved arterial function in patients with peripheral arterial disease (PAD).


METHODS
Individuals with PAD were randomly assigned to receive 400 microg folic acid (45 patients) or 5-methyltetrahydrofolate (5-MTHF) (48) daily, or placebo (40) for 16 weeks. Primary endpoints were changes in plasma total homocysteine (tHcy), ankle : brachial pressure index (ABPI) and pulse wave velocity (PWV). Secondary outcomes were changes in plasma inflammatory markers.


RESULTS
Plasma tHcy was significantly reduced in folic acid and 5-MTHF groups compared with controls: median difference: - 2.12 (95 per cent confidence interval - 3.70 to - 0.75) micromol/l (P = 0.002) and - 2.07 (-3.48 to - 0.54) micromol/l (P = 0.007) respectively. ABPI improved significantly: median difference 0.07 (0.04 to 0.11) (P < 0.001) and 0.05 (0.01 to 0.10) (P = 0.009) respectively. Brachial-knee PWV (bk-PWV) decreased significantly in individuals receiving 5-MTHF and tended to be reduced in those taking folic acid compared with controls: median difference: - 1.10 (-2.20 to - 0.20) m/s (P = 0.011) and - 0.90 (-2.10 to 0.00) m/s (P = 0.051) respectively. Plasma levels of inflammatory markers were not affected.


CONCLUSIONS
Folate administration reduced plasma homocysteine, and slightly improved ABPI and bk-PWV.
Khandanpour
N
N
Vascular Unit, Norfolk and Norwich University Hospital NHS Trust, Norwich, UK. nkh950@yahoo.com
Armon
M P
MP
Jennings
B
B
Finglas
P M
PM
Willis
G
G
Clark
A
A
Meyer
F J
FJ
D000368:Aged; D000369:Aged, 80 and over; D055109:Ankle Brachial Index; D001783:Blood Flow Velocity / Q000187:drug effects; D002317:Cardiovascular Agents / Q000008:administration & dosage*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage*; D006710:Homocysteine / Q000378:metabolism; D006801:Humans; D007383:Intermittent Claudication / Q000097:blood / Q000178:diet therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D013763:Tetrahydrofolates / Q000008:administration & dosage*; D016896:Treatment Outcome
D002317:Cardiovascular Agents; D013763:Tetrahydrofolates; D006710:Homocysteine; D005492:Folic Acid; C005984:5-methyltetrahydrofolate