When Brain Shuts Down, Legs Kick into Overdrive

It's maddening to have a feeling that you can't explain. When I was a kid on long car rides, I would sometimes experience a strange sensation in my legs. I felt like I had to move my legs. When I did, the feeling would go away for a few seconds but then come back.

It struck at the worst times — my legs kept me awake when I was tired and needed to sleep. As an adult, the feeling periodically comes back to haunt me, during a slow movie, on airplane rides, or having a late drink at a bar, or just around bedtime. Always when my brain is half-disengaged.

I had no idea what this was until a few years ago when I found a Web site about something called Restless Legs Syndrome (RLS). I had that eureka moment people must have when they find out that what ails them has a name. "Yes!" I thought, "THIS IS WHAT I HAVE!"

My case is fairly tame. People with severe forms of Restless Legs Syndrome are sleep deprived and miserable.

Jumping Legs

The number of people affected by RLS is somewhat uncertain, but one large study found that almost 8 percent of people in the United States have experienced restless legs sometime in the past year. Three percent are bothered by it two or more times a week. And "bothered" probably isn't the right word — the study categorizes these people as experiencing "moderate or extreme distress."

People with RLS sometimes describe a "tugging" or "creepy crawly" sensation. Until recently, an average physician was unlikely to know what it was.

There are some early references to what appears to be RLS in the scientific literature. An English physician named Thomas Willis wrote a description in 1683:

"Wherefore to some, when being in bed they betake themselves to sleep, presently in the arms and legs. Leaping and contractions of the tendons and so great a restlessness and tossing of the members ensure, that the diseased are no more able to sleep, than if they were in the place of the greatest torture!"

But that was it, for about 250 years. Then, in the 1940s, a researcher made a more detailed study, and more work has been done in the past decades.

Today, there is a Restless Legs Syndrome Foundation, dedicated to getting the word out and encouraging research. Bob Waterman served as chairman of the foundation, and says RLS affects him almost every night. He hid his condition for years because, he says, it just seemed strange.

"I just get very fidgety," he says "I make people nervous just to look at me."

One of the foundation's goals is education — and Waterman speaks freely about his condition now.

"One of the funniest things is to visit one of our board meetings," Waterman says. "You see people lying around with their legs up against the wall, or walking around. It's very amusing. You really wonder how we get any work done."

Growing Body of Research

A small community of scientists now studies Restless Legs Syndrome. David Rye is a neurologist at Emory University and director of the Emory Healthcare Program in Sleep. Rye also has the disorder and has used himself as a guinea pig. At one point, he attached a special device to his leg to measure how often he kicked while he was asleep. Rye says there is good evidence the condition has a strong genetic component.

"If you go to a clinic [for RLS], 65 to 75 percent of the patients will tell you they have a first-degree relative with RLS."

Rye thinks he and others are close to finding a gene.

It is unclear what causes the irresistible desire to move. Christopher Earley, a neurologist at Johns Hopkins University thinks it has something to do with low levels of iron in the brain. His group has measured iron in the spinal fluid of people with RLS (which he says gives you some idea of what's going on in the brain) and found these patients tended to have reduced iron levels.

Earley isn't sure why the feeling seems to strike people when they are tired, but he imagines that when someone is busy or moving around, the brain is exerting strong control over the body. When a person gets tired and the conscious brain begins to check out — that's when quieter signals can get through.

Earley has a pet theory that RLS may be the body's way of reacting to reduced iron in the brain and saying, in essence, "Go get some iron!"

"5,000 or 10,000 years ago, the major source of iron was meat," he says. "So the guy out running around... was more likely to find meat and iron than the other guy sitting warmly in his cave keeping comfortable."

Studies indicate the RLS is more common in people from Scandinavia and northern Europe. Earley jokes that this could explain the trips taken by the Vikings.

"What could possibly possess a bunch of guys to get in a boat in the middle of winter and row across the Atlantic," he says, "other than a bad case of restless legs!"

Treatment for Restless Legs Syndrome

Some physicians recommend eliminating alcohol and exercising regularly to decrease the symptoms of RLS. I've found both of these help.

There are also a variety of drugs that can be used to treat RLS. You may have seen ads on television for GlaxoSmithKline's drug Requip. Requip, like some other medications used for RLS, boosts production of the neurotransmitter dopamine in the brain.

But physicians say no drugs work perfectly. And dopamine boosters all have a potential drawback — when used past a certain point, some patients experience "augmentation." In other words, their symptoms get worse.

One of the first dopamine drugs used to treat RLS was the medication containing levodopa, often used for Parkinson's. It seemed to work miracles for RLS, and neurologist David Rye says patients were eternally grateful when they started taking it.

"They would remain happy for weeks to months," he says. "Then invariably you'd get a phone call saying they were worse than when they first came to see you. What they were screaming and describing to you is not something you would want to repeat to your children."

Some physicians worry that (in part because of the ads on television) people with mild RLS will take medications they don't really need. Steven Woloshin, a professor at Dartmouth College calls RLS the "poster child for disease mongering."

Bob Waterman, who served as chair of the Restless Legs Syndrome Foundation, takes what he calls a "bouquet" of drugs, and says they help. But like many people with the condition, he has also developed an elaborate series of home remedies. He takes hot or cold baths, or tries to occupy his mind by painting or playing video games (Tomb Raider was his favorite for a while.)

Waterman says his wife is accustomed to him crawling out of bed to get on the exercise bicycle for a half-hour in the middle of the night.

"Our whole married life is me crawling around and her trying to get some sleep," he says.

Waterman says he sometimes wonders if his ancestors were night watchmen.

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