Antioxidants May Impede Statin Drugs' HDL-Raising Properties

SEATTLE--In the August Arteriosclerosis, Thrombosis, and Vascular Biology (21: 1320-6, 2001) (http://atvb.ahajournals.org), researchers reported that antioxidant vitamins and minerals may help statin drugs reduce overall cholesterol levels but, when combined with those drugs, they may impede the drugs' ability to increase "good" cholesterol levels.

In a 12-month study of 153 patients with coronary artery disease and low levels of HDL cholesterol, subjects were randomly assigned to one of four groups taking 1) cholesterol-regulating drugs (simvastatin with niacin); 2) antioxidants (vitamins C and E, beta carotene and selenium); 3) a combination of statins and antioxidants or 4) a placebo.

Both the statin and statin/antioxidant groups had significant reductions in plasma cholesterol, triglyceride and LDL ("bad") cholesterol. However, HDL improved in the statin participants while remaining the same in the antioxidant subjects. Researchers, led by Marian Cheung, Ph.D., from the University of Washington, concluded that antioxidants impeded the beneficial HDL-raising properties of statin drugs.

In an accompanying editorial (p. 1253) by Lewis Kuller, M.D., Ph.D., from the University of Pittsburgh, stated that there was no way of knowing which of the four nutrients is the "one or ones [that] are the culprit or whether it is the antioxidants overall that have an adverse effect." He also wrote that patients should not take more than the recommended dietary allowances for the prevention or treatment of cardiovascular disease until more is known about their possible counteractions for statin drugs.

"I was surprised after hearing about this study," said W.H. Leong, vice president of sales and marketing at Carotech, manufacturer of vitamin E ingredients. "I couldn't understand how antioxidants could interfere with these drugs. When looking at the totality of vitamin E studies out there, they still show more of a benefit for heart disease risk."