This Vitamin May Help Lower Stroke Risk

Folic acid with enalapril may reduce stroke risk more than enalapril alone

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) As stroke becomes an increasingly common health risk, researchers look for ways patients can lower their risk. And they might have found one.

When taken with a blood pressure medication called enalapril, folic acid (a B vitamin) appeared to lower stroke risk more than taking enalapril but not the vitamin, a new study found.

Strokes are caused by poor blood flow to the brain, often resulting from blood clots or blood vessels in the brain that burst. A stroke can lead to paralysis on one side of the body and problems with speech or thinking.

“We speculate that even in countries with folic acid fortification and widespread use of folic acid supplements such as in the United States and Canada, there may still be room to further reduce stroke incidence using more targeted folic acid therapy,” wrote the study authors, led by Yong Huo, MD, of Peking University First Hospital in Beijing.

Dr. Huo and team found that the supplement was most useful in people with a genetic risk of having low folic acid levels and those whose folic acid levels were already low before starting the study.

This study looked at more than 20,000 adults in China with high blood pressure (a known risk factor for stroke). None had ever had a stroke or heart attack.

These patients were randomly assigned to take 10 milligrams (mg) of enalapril every day or 10 mg of enalapril and 0.8 mg of folic acid. They were 40 to 75 years old, and were followed for an average of 4.5 years.

In that time, 3.4 percent of those on the enalapril alone had strokes (355 people), compared with only 2.7 percent (282 people) of those taking the medication and the supplement.

The main goal was to cut the chance that a person would have his or her first stroke, but the study authors also found there were fewer heart-related incidents, such as heart attack, in the group taking folic acid.

Loyola University Medical Center neurologist Michael Schneck, MD, said he had doubts about whether this study would help many Americans.

"While this Chinese study suggested a benefit of folate supplementation, similar studies in North America, Europe and Australia did not confirm a benefit," Dr. Schneck told dailyRx News, noting that he was a researcher in one of those studies. "The assumption is that in the ‘Western World’ where folate supplements occur in food, additional folic acid is of limited benefit. Thus, supplements may not help in stroke prevention. Folate supplements probably won’t hurt, but they may not help."

In an editorial about this study, Meir Stampfer, MD, and Walter Willett, MD, of the Harvard T. H. Chan School of Public Health in Boston, wrote that they felt the results of this study were so strong that another study to support these findings may not be needed.

“It is possible to debate the ethics of whether a replication trial should be performed, especially because folic acid supplementation (or fortification) is safe and inexpensive, and carries other benefits,” they wrote.

Folate is available in fortified foods like milk in the US. It is also found in dark green vegetables like spinach and broccoli, citrus fruits, beans and peas.

The study and editorial were published March 15 in JAMA.

Funding came from a variety of sources, such as the National Clinical Research Center for Kidney Disease and the Shenzhen Municipal Government. Various study authors made disclosures, such as grants from the National Science Foundation and AUSA Research Institute.

Review Date: 
March 13, 2015
Last Updated:
March 20, 2015