Restless legs syndrome: Sign of heart trouble?

(CBS/AP) Poor sleep may not be the only health problem caused by restless legs syndrome (RLS). New research suggests that people who have the controversial condition may be suffering from hidden heart problems.

In a recent study conducted at the Mayo Clinic, people with the condition were more likely to have thick hearts - a condition that makes them more prone to cardiac problems, stroke and death.

"We are not saying there is a cause-and-effect relationship," just that restless legs might be a sign of heart trouble that doctors and patients should consider, said study leader Dr. Arshad Jahangir, a heart rhythm specialist at the Mayo Clinic Arizona in Scottsdale. He gave results of the study Sunday at a meeting of the American College of Cardiology in New Orleans.

RLS is thought to affect millions, though some doctors think its seriousness has been exaggerated, possibly to help sell treatments. The syndrome gained more scientific respect several years ago, when several genes were linked to it. And doctors have long known that other sleep disturbances such as sleep apnea up the risk of heart problems. The study suggests the same may be true of the syndrome, famously referred to as "the jimmy legs" in an old episode of the TV comedy "Seinfeld."

The study involved 584 people diagnosed with the syndrome based on four widely used criteria. Participants were given an imaging test that their allowed heart thickness to be measured, and were kept overnight so their sleep could be monitored. Afterward, researchers divided them into two groups based on the frequency of leg twitches.

The 45 percent who twitched at least 35 times per hour were more likely to have the thick-heart condition than those who kicked less often.

Looking at all study participants about three years later, researchers saw that those with severely thick hearts - about a quarter of the total group - were more than twice as likely to have suffered a heart problem or to have died.

People with restless legs shouldn't panic, but it's worth talking with doctors about whether more tests are needed to look for an enlarged heart, Jahangir said.

"Don't ignore it," he said. "Discuss it with your physician."