Q & A on Benefits of Coenzyme Q10

A 3-year Australian study found that when patients who underwent bypass surgery were given coenzyme Q10 for a week or more before the operation, their heart muscle tolerated stress better, recovered more quickly, and had better pumping ability after surgery than did the heart muscle in patients given placebo.1
Should patients who are scheduled to undergo bypass surgery routinely be given coenzyme Q10 before the operation?
—Richard S. Banfield, MD
  New Canaan, Conn

REFERENCE:
1. Rosenfeldt F. Paper presented at: Second Conference of the International Coenzyme Q10 Association; December 2000; Frankfurt/Main, Germany.

The benefits of coenzyme Q10 (ubiquinone) in both cardiac and noncardiac conditions have been widely touted. Unfortunately, data are not as strong as proponents often state. Many of the studies are unblinded or not randomized. The well-designed studies tend to be small, and the results are often negative.1,2

Although long-term coenzyme Q10 therapy for patients with congestive heart failure has been advocated, the compound is very expensive and its benefits remain unproven. Similarly, the data for perioperative use of coenzyme Q10 are generally uncontrolled and unblinded.

Dr Rosenfeldt's data regarding ubiquinone are provocative; however, numerous parameters affect the length of hospital stay, and it is difficult to believe that a simple intervention could have such a profound effect. Indeed, many small studies have demonstrated great benefit, while subsequent large-scale studies (eg, the ELITE studies3 and the vesnarinone trials4) had negative results. Thus, confirmatory studies need to be done before routine administration of coenzyme Q10 can be recommended for patients who are to undergo bypass surgery.

Stephen S. Gottlieb, MD,
  Professor of Medicine
  University of Maryland
  Baltimore

REFERENCES:
1. Watson PS, Scalia GM, Galbraith A, et al. Lack of effect of coenzyme Q on left ventricular function in patients with congestive heart failure. J Am Coll Cardiol. 1999;33:1549-1552.
2. Khatta M, Alexander BS, Krichten CM, et al. The impact of coenzyme Q10 in patients with congestive heart failure. Ann Intern Med. 2000;132:636-640.
3. Pitt B, Poole-Wilson PA, Segal R, et al, for the Losartan( Heart Failure Survival Study ELITE II. Effect of losartan compared with captopril( on mortality in patients with symptomatic heart failure: randomised trial. Lancet. 2000;355:1582-1587.
4. Cohn JN, Goldstein SO, Greenberg BH, et al, for the Vesnarinone Trial Investigators. A dose-dependent increase in mortality with vesnarinone among patients with severe heart failure. N Engl J Med. 1998;339: 1810-1816.