Low Vitamin C Associated With Heart Attacks
NEW YORK (Reuters) -- Among patients who have coronary atherosclerosis, low blood levels of vitamin C are significantly associated with recurring chest pain or a heart attack, a study indicates.
The researchers who published the findings speculate that vitamin C may help to keep the fatty deposits inside the arteries from rupturing and causing unstable angina or a heart attack.
"The study is another piece of the puzzle that helps explain what's wrong with blood vessels that predisposes them to go on and cause a problem like a heart attack," Dr. Joseph A. Vita of Boston University, Massachusetts, said in an interview with Reuters. "It seems that lower levels of vitamin C may be involved in the abnormalities in the arteries of patients who have these problems."
Vita and his colleagues studied 149 patients, aged 50 to 74, using cardiac catheterization -- an imaging procedure that lets doctors visualize the inside of the heart and coronary arteries. In 129 of these patients, at least one coronary artery was more than halfway blocked with deposits.
The research team further categorized the patients into 65 patients who had stable angina and 84 patients who had an unstable coronary syndrome, which they defined as unstable angina or a heart attack within the previous 2 weeks.
Angina -- chest pain caused by insufficient blood flow to the heart -- is said to be unstable if it worsens suddenly or recurs over days and weeks.
Among the 129 patients with significant artery blockage, low blood levels of vitamin C correlated with unstable coronary syndrome, Vita's team reports in the April issue of the Journal of the American College of Cardiology. Conversely, the researchers did not find any correlation between unstable coronary syndrome and the extent of the deposits inside the coronary arteries.
Vitamin C does not seem to reduce the buildup of deposits, Vita and his colleagues conclude.
Vita explained that the study findings do not prove that taking vitamin C or other antioxidants would have protected patients from developing unstable angina or having a heart attack. "We and several other investigators are working on that question, but we don't have an answer," he told Reuters.
"We do not yet recommend vitamin C for patients with coronary disease," Vita emphasized. "We simply don't have any proof that it's beneficial. But our study would help answer the question of why antioxidants work, if they turn out to work."
SOURCE: Journal of the American College of Cardiology (1998;31:980-986)