Can CoQ10 Treat Heart Disease?

By Elizabeth Shimer

Several years ago, in a few small-scale studies, coenzyme Q10 (coQ10) had seemingly proven itself to be a tough soldier in the war against congestive heart failure. Results of a recent study presented at the 72nd Scientific Session of the American Heart Association in November of 1999, suggest that, at least below certain blood levels of coQ10, this supplement may not be so powerful after all as a means for treating elderly patients with heart disease.

Clinically, coQ10 had been shown to bolster energy production and antioxidant activity. In addition to its possible role in the treatment of heart failure, other small studies have also deemed coQ10 helpful to patients in the prevention and treatment of angina, coronary artery disease, high blood pressure, and other cardiovascular conditions. But this new research, gathered by Stephen S. Gottlieb, M.D.,and his colleagues, challenges one element among coQ10’s potential health benefits?its role in preventing heart failure among elderly patients with heart ailments.

Gottlieb evaluated the effects of coQ10 on both ejection fraction (a measure of the heart muscle’s strength and how hard it pumps) and tolerance for exercise in heart disease patients. His subjects consisted of 39 men and 7 women, all heart patients over the age of 64. Forty-two of the patients had marked limitation of activity and experienced symptoms when they attempted less than ordinary bouts of activity; the remaining four were unable to carry on any physical activity without discomfort and had symptoms at rest. Gottlieb gave the patients a daily dose of 200 milligrams of either coQ10 or a placebo for six months.

After six months, there was no improvement in ejection fraction, exercise tolerance, or any other heart disease symptoms in either the coQ10 or the placebo patients, so it seems Gottlieb’s results weaken the argument for coQ10’s power in the therapy of congestive heart failure. Critics of the study, however, noted that the patients may not have raised the concentrations of CoQ10 in their blood to sufficiently high levels. CoQ10 experts assert that in order for coQ10 to be effective against heart disease, blood level concentrations of at least 2/5-3.5 ?g/ml (micrograms per millileter) must be met. According to Gottlieb, blood concentrations of coQ10 in the patients at the end of this study ranged from .95 – .62 ?g/ml to 2.2 – 1.2 ?g/ml?below the recommended concentration level.

Proponents of coQ10 also note that there is a wide variance in the absorption rate of coQ10 products. Some are better absorbed than others; powders in general are thought to be poorly absorbed, so you need to take a higher dose in order to achieve the level of concentration that you might get, say, from a water-soluble or gel-type of coQ10. This question of coQ10 absorption is the subject of ongoing research, but it may be an important factor in determining whether Gottlieb’s subjects took enough coQ10 for it to have been of cardiovascular benefit.

In the meantime, take heart: Gottlieb’s small study focused on just one kind of heart problem. The antioxidant power of coQ10 continues to be studied for its potential benefits in treating a variety of conditions. Other small double-blind, controlled studies have shown coQ10 to be moderately effective in treating hypertension. And, science is a

trial and debate process’so stay tuned!


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