This article is more than 5 years old. Information may no longer be current.
Folic acid supplementation for homocysteine reduction yields no effect on vascular outcomes
Clarke R. Arch Intern Med. 2010;170:1622-1631.
Click Here to Manage Email Alerts
Data from a meta-analysis of eight randomized trials demonstrated that folic acid supplementation to reduce homocysteine levels did not significantly affect CV events, cancer or mortality in patients at higher risk for CVD.
“Elevated plasma total homocysteine has been suggested as a potentially modifiable risk factor for CHD, stroke and other occlusive vascular conditions,” the researchers wrote.
However, the researchers found that lowering homocysteine levels by 25% for 5 years did not significantly affect the incidence of major vascular events during the treatment period.
The meta-analysis included eight randomized, placebo-controlled trials of 37,485 patients at high risk for CVD. Participants were randomly assigned to receive folic acid (n=18,723) in doses ranging from 0.8 mg per day to 40 mg per day or to placebo or a small dose of folic acid (n=18,762). Median duration of treatment was 5 years.
During the treatment period, 3,990 major coronary events, 1,528 strokes and 5,068 revascularizations occurred, as well as 3,010 cancers and 5,125 deaths. Folic acid supplementation resulted in an average reduction of 25% in homocysteine levels but was not associated with significant effects on vascular outcomes. The rate ratios were 1.01 (95% CI, 0.97-1.05) for major vascular events, 1.03 (95% CI, 0.97-1.10) for major coronary events and 0.96 (95% CI, 0.87-1.06) for stroke.
Similarly, there was no significant effect on cancer outcomes during the treatment period. The rate ratio was 1.05 (95% CI, 0.98-1.13) for overall cancer incidence, 1.00 (95% CI, 0.85-1.18) for cancer mortality and 1.02 (95% CI, 0.97-1.08) for all-cause mortality.
Additionally, folic acid supplementation did not significantly affect vascular outcomes in any subgroups and did not affect overall vascular mortality, according to the researchers. Participants who experienced larger reductions in homocysteine levels did not experience any benefit, and longer duration of treatment did not trend toward increasing benefit.
“Although the lack of any other benefits is disappointing (albeit fairly definitive), the lack of any significant adverse effects on vascular events, cancer incidence, cancer mortality and overall mortality provides reassurance about the safety of population-wide folic acid fortification,” the researchers wrote.
 |
Follow CardiologyToday.com on Twitter. |