MONDAY, Feb. 18, 2008 (HealthDay News) -- Statins such as Crestor, Lipitor or Zocor that are prescribed to lower cholesterol levels may also cut the risk of atrial fibrillation, the abnormal heartbeat that boosts the odds of a stroke, French researchers report.
An analysis of six controlled studies with more than 3,500 participants showed that those patients who received statins had a decreased risk of incidence or recurrence of atrial fibrillation, said lead researcher Dr. Laurent Fauchier, a professor of cardiology at the Centre Hospitalier Universitaire Trousseau in Tours.
His team will publish the findings Feb. 26 in a special issue of the Journal of the American College of Cardiology that focused on atrial fibrillation.
Atrial fibrillation occurs when the two upper chambers of the heart quiver rather than beating in a coordinated way. Blood can pool in the chambers, and clots can form that travel to the brain, causing a stroke. The incidence of atrial fibrillation rises with age and experts estimate that the condition is present in more than 5 percent of Americans over the age of 70. One 2006 study put the number of Americans with atrial fibrillation at over 5 million.
Participants in the trials either had experienced atrial fibrillation in the past or had a high risk of the condition after a heart attack or bypass surgery.
Overall, those who got statins had a 61 percent lower risk of developing atrial fibrillation than those who did not, the analysis found.
Still, the time has not yet come when statin therapy can be recommended for treatment of atrial fibrillation, Fauchier said.
"I think it is too early to use statins only for atrial fibrillation," he said.
That belief was echoed by Dr. Christopher Cannon, an associate professor of medicine at Harvard Medical School and a cardiologist at Brigham and Women's Hospital, Boston. Cannon is also a senior investigator in the TIMI (Thrombolysis in Myocardial Infarction) Group, which has done studies on statins and atrial fibrillation.
"It would be nice to see a larger number of patients studied for longer periods," Cannon said.
The new analysis shows that statin therapy "is very encouraging as a potential treatment for preventing atrial fibrillation, but larger studies are needed before it is used widely," he said.
Cannon noted that the largest study included in the report did not see a significant difference in the incidence of atrial fibrillation, "but that was just for a short period of time, four months."
As for the mechanism by which statins might reduce atrial fibrillation, it probably has nothing to do with their cholesterol-lowering ability, Cannon said. "We believe that statins reduce inflammation," he said. "That would be a mechanism to reduce incidence of atrial fibrillation, which could be related to inflammation around the heart."
The French report provides a reminder to cardiologists about the value of continuing statin therapy for people who undergo bypass surgery because of blocked coronary arteries, Cannon added.
"In bypass surgery, that can be overlooked because the doctor is focusing on short-term goals," he said. "This study suggests that it is reasonable to keep patients on statins during their hospital stay. It might have some benefits."
In the same issue of the journal, experts set forth a new set of performance measures developed by the American Heart Association and the American College of Cardiology, in collaboration with the Heart Rhythm Society, to monitor care delivered to people with the condition.
The new guidelines include the use of a point system to track those patients at highest stroke risk, prescribing blood thinners such as warfarin (Coumadin) to cut the odds of stroke, and monitoring warfarin's effects on a monthly basis.
There's more on atrial fibrillation at the American Heart Association.