I'm not antagonistic to the use of CoQ10 by others, but I suggest caution in determining its benefits, efficacy, and contraindications.
The links provided in the mentioned post for CoQ10 are interpretational monologues citing carefully selected favorable studies, some of which are old and have been since discounted. Both articles linked refer to subsets of the same, few favorable studies and articles, two of which are test tube studies, one which is not a study, but an interpretation of other studies, another which is a rat study, and another citing patients being released from the hospital earlier on CoQ10 - by the choice of the same doctors who were doing the funded research.
The studies cited were all small. The most interesting one to me, and referred to in the other post, purported to show that CoQ10 levels were significantly improved in atrial tissue after OHS. This study included only 24 individuals,
including those taking the placebo. The articles failed to mention that the significant increases were found in the tissues of some patients over 70, and not in all the patients. The studies and articles appeared in small trade journals, rather than the NEJM, The Lancet, or other major publications.
Looking at other sources that do not gain financially from reporting on herbal/nutritional supplements:
The Mayo Clinic site comments found most often in listings of proposed uses of CoQ10 are "Most trials are small or not well designed," "results are variable," and "Better research is needed in this area."
http://www.mayoclinic.com/health/coenzyme-q10/NS_patient-coenzymeq10
The Linus Pauling Institute Micronutrient Information Center, as posted on the Oregon State Education Infocenter site, sends more specific messages regarding efficacy and conditions of usage:
"...it is not clear whether oral supplementation increases coenzyme Q10 concentrations in other tissues of individuals with normal endogenous coenzyme Q10 synthesis. Oral coenzyme Q10 supplementation of young healthy animals has not generally resulted in increased tissue concentrations, other than in the liver, spleen, and blood vessels (15, 16). Supplementation of healthy men with 120 mg/d for 3 weeks did not increase muscle concentrations of coenzyme Q10 (17). "
"Although one study in the 1970's found that weekly coenzyme Q10 injections increased the lifespan of mice, those results have not been replicated. In more recent studies, lifelong dietary supplementation with coenzyme Q10 did not increase the life spans of rats or mice (15). Presently, there is no scientific evidence that coenzyme Q10 supplementation prolongs life or prevents age-related functional declines in humans."
"...there is little evidence that it improves athletic performance in healthy individuals...Two studies actually found significantly greater improvement in measures of anaerobic (60) and aerobic (61) exercise performance after supplementation with a placebo compared to coenzyme Q10"
http://lpi.oregonstate.edu/infocenter/othernuts/coq10/index.html
On a Q10-positive note, there is agreement that in certain disease conditions, reduced levels of CoQ10 generally exist, but there is a lack of evidence that raising the amount of serum CQ10 has a positive effect on the disease states. There is no case made for health improvements in healthy individuals.
There is general agreement that supplementation can assist for cases of CoQ10 deficiency, but the concensus is that it's very uncommon, generally linked to genetic mitochondrial problems. (Per the Linus Pauling Institute: ""No coenzyme Q10 deficiency symptoms have been reported in the general population.")
Areas in which there are small, but positive studies include some possible benefits for those over 70 who may have lower levels of the chemical. Also, small trials showed some short-term gains for some patients undergoing CABG. The results are not stratified by age groups, and may also relate to an over-70 connection. The studies have small subject groups, and there were no followups to see if any perceived advantage remains beyond the first days following surgery.
As far as drug interactions, the Pauling Institute indicates that CoQ10 reduces the effects of warfarin (Coumadin), apparently in a way that can be measured via INR, so test and dose the diet, if you're taking it, and don't go on and off it too much. Check Al Lodwick's site to see what he says.
As mentioned in earlier posts, oral doses are antagonistic to beta blockers, which most valve patients take for at least a while after surgery.
There are very mixed results in studies involving statins, such as Lipitor and Pravachol. Older studies say they reduce CoQ10 levels. Newer studies say they don't. Simvastatin has been shown to reduce serum (blood) CoQ10 levels in rats, but there are no studies that show the same effect in humans. The older Lipitor and Pravachol studies may have been largely animal studies as well, suggesting that human CoQ10-cholesterol relationships may not respond in the same way as those in rodents and dogs. I'm no fan of statins, but the jury is still out on this one.
Other cautions (this from Pauling again): CoQ10 may lower blood sugar levels. Caution is advised in patients with diabetes or hypoglycemia, and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.
Best wishes,
