Friday, October 19, 2012

Creatine: Bad for the heart? by Jerry Brainum

     One indirect gauge of the effectiveness of sports supplements is the amount of criticism directed at them. Supplements that work as advertised seem to attract more attention. Examples include ephedrine-and-caffeine combinations that were banned for one year by the FDA due to often dubious adverse-effect reports, then restored to the market by a federal judge because of a lack of sufficient scientific evidence concerning their potential dangers to health when used in suggested doses. Another example is the pro-hormone supplements, which fell victim to the ongoing hysteria about anabolic steroids. The final versions of them were remarkably effective and produced few or no side effects when used as directed. Their biggest problem was that they attracted too much attention—and because a few of them actually were anabolic steroids or contained so-called designer steroids.
     It was perhaps only a matter of time before creatine was accused of endangering health. That’s evident in reports that it is linked to kidney failure, muscle cramps and liver damage, none of which are even remotely true.
      Some reports to the FDA have even claimed that using creatine led to heart problems. Since creatine is a natural constituent of the human body, synthesized from amino acids in the liver, pancreas and kidneys, it’s hard to justify an accusation like that. Nevertheless, a recent case report linked the use of supplemental creatine to atrial fibrillation, a disturbance of heart rhythm.1
      Atrial fibrillation involves a disturbance in the contraction of the atrial, or upper, chambers of the heart. The incidence of this disorder doubles with each decade of life, so it’s far more common in older people. The most frequent cause is long-term hypertension, or high blood pressure, which may damage the heart. The errant heart rhythm may lead to more clots being released into the blood—embolisms that may then travel to the brain, inducing stroke. Doctors prevent that effect by providing anticoagulants, such as Warfarin, to those afflicted with the condition.
     When atrial fibrillation occurs without any evidence of structural heart damage, it’s called lone atrial fibrillation. While it’s rare in younger people, it can be produced by scar tissue forming in the atrial chambers of the heart, hypersensitivity due to neural stimulation of the heart or an inflammation in the heart. The most common causes, however, are drug use, including excessive caffeine intake, acute alcohol intoxication and using too much thyroid drugs (many bodybuilders have experienced it after using excessive amounts of the thyroid drug Cytomel).
      In the case study a 30-year-old man without any prior evidence of heart problems reported to a hospital emergency room, complaining of heart palpitations and rapid breathing, both of which had occurred abruptly within the previous 48 hours. An electrocardiogram indicated atrial fibrillation. The man denied using any drugs, and none showed up in his medical tests. He did, however, admit to using creatine supplements. He’d begun by taking 20 grams a day for five days, a loading phase, followed by a maintenance dose of 2.5 grams daily for one month.
      That much creatine produced cramping and diarrhea, so he curtailed it for a month, then switched to a capsule form. He developed the heart symptoms while taking a loading dose of the creatine capsules. He was treated with intravenous drugs to prevent clot formation and to stabilize his irregular heart rhythm. The treatment proved effective, as his heart returned to normal rhythm in eight hours. He was discharged within 24 hours and told to take aspirin and a beta-blocking drug for his heart.
      In discussing this man’s case, the author asserts that since creatine is known to cause dehydration and diarrhea, it may have caused an electrolyte, or mineral, imbalance that led to the atrial fibrillation. Yet the man’s primary electrolytes, potassium and magnesium, were within normal values. While it has been frequently reported anecdotally that creatine causes dehydration, there’s no documented evidence in the medical literature that points to it. Since creatine may promote a shift of water from extracellular to intracellular compartments in the body, it may adversely affect electrolyte balance that way, but that would happen only during restricted fluid intake. The odds that creatine would cause an effect significant enough to produce a lone atrial fibrillation are remote at best.
       So why did the man in the study experience atrial fibrillation after he took creatine? He may have had an inherent sensitivity to creatine, or the creatine may have induced a neural stimulation of his heart. The latter effect is more likely, since the man was a vegetarian, and vegetarians have lower creatine stores in their bodies. The loading dose may have had a druglike effect on him. The solution would be to avoid the creatine load, which is a dubious technique anyway, and take no more than five grams, or one teaspoon, a day. In 30 days that will result in the same level of creatine storage in muscle as a one-week load, minus any possible side effects.
      One other aspect to consider is that if anything, creatine would be beneficial for the heart. A feature of heart failure is the lack of production of energy compounds, such as ATP. Anything that boosts ATP production in the heart would aid heart function. Several supplements, such as coenzyme Q10, ribose and creatine, have all been shown to do just that.
1 Kammer, R.T. (2005). Lone atrial fibrillation associated with creatine monohydrate supplementation. Pharmacotherapy. 25:762-764.

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

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