Long-term study, involving women, deals another blow to homocysteine theory
TUESDAY, May 6 (HealthDay News) -- Folic acid and vitamin B supplements aimed at reducing blood levels of the amino acid homocysteine did not protect women against heart disease and stroke, a long-term study found.
It's the latest of several trials to douse the hope that lowering homocysteine levels could reduce the incidence of cardiovascular disease, said study lead author Dr. JoAnn Manson, chief of preventive medicine at Harvard's Brigham and Women's Hospital in Boston.
"To our knowledge, this is the trial with the longest follow-up," Manson said. "And to date, it is the largest study of women."
The trial also included a large number of women without cardiovascular disease, she said. Most earlier studies concentrated on people who already had had a heart attack, stroke or other cardiovascular problem.
The new findings were published in the May 7 issue of the Journal of the American Medical Association.
The trial included more than 5,400 U.S. women who were health professionals. Some had a history of cardiovascular disease, and others had three or more coronary risk factors, such as high blood pressure, obesity or diabetes. Half of the women took a daily combination pill containing 2.5 milligrams of folic acid, 50 milligrams of vitamin B6, and 1 milligram of vitamin B12, while the other half took a placebo.
Over the next 7.3 years, 14.9 percent of the women taking the active pill had a cardiovascular event, such as a heart attack or stroke. The incidence of such events in the women taking the inactive pill was almost the same -- 14.3 percent.
There still are ongoing trials, all stimulated by past studies suggesting an association between high blood levels of homocysteine and cardiovascular disease. But the latest results "cast further doubt on the hypothesis that lowering homocysteine prev
All rights reserved