Breakthroughs in Restless Legs Syndrome Treatment
Is there a connection between restless legs syndrome and a host of other conditions, including heart disease and hypertension? Researchers are conducting studies to see how certain disorders affect one another. On paper, restless legs syndrome (RLS) sounds about as serious as an itchy toe. That may explain why, despite afflicting about 12 million people in the U.S., the condition often goes misdiagnosed.
In fact, it may be the most common disorder that nobody has heard about, says Arshad Jahangir, M.D., professor of medicine at Mayo Clinic in Arizona.
Restless legs syndrome is characterized by a creeping, painful feeling in the legs and an irresistible urge to move. It’s worse when you sit still or lie down, and is more troublesome in the evening. For some patients, the condition is merely an annoyance.
But new research has revealed that some patients with RLS may be at higher risk of heart disease, hypertension, recurring bouts of RLS after pregnancy and other diseases.“Don’t take [RLS] lightly,” says Jahangir, who is one of several researchers in the past year who has published new studies on the nervous system disorder.
Read on for the latest research breakthroughs from Jahangir and other medical scientists.
1. Heart Conditions Linked to Restless Leg Syndrome
What it’s about: Older restless legs syndrome patients with more severe cases of the disease also are more likely to also have a condition marked by a tightening of the heart muscles, according to a new study. That may be a sign of high blood pressure, a precursor to such life-threatening health risks as heart attacks, experts say.
The 2010 study, led by Jahangir, included 584 patients with RLS. Researchers measured patients’ leg twitches at night, when RLS symptoms typically worsen.
Those results were compared with the results of patients’ echocardiograms, diagnostic tests that look for left ventricular hypertrophy.
That’s a heart condition in which the muscle tissue making up the wall of the heart’s main pumping chamber, the left ventricle, is enlarged, according to Mayo Clinic.Those whose legs were most affected by RLS symptoms were more likely to suffer from the heart ailment.
It’s possible, he says, that RLS may simply exacerbate an existing heart problem, rather than cause one. “If someone already has borderline tightening of the heart muscle, and you add the restless legs syndrome symptoms, they are more at risk,” he says.
But Jahangir cautions that more research is needed before applying this study to the general population. “It’s a little early to say what can be recommended for every RLS patient,” Jahangir says.
Bottom line: In the meantime, people with restless legs syndrome should avoid well-established risk factors for heart conditions, such as smoking, lack of physical activity, uncontrolled diabetes and too much stress, Jahangir advises.
2. Hypertension and Restless Legs Syndrome
What it’s about: Middle-aged, female RLS patients are at higher risk for hypertension and should monitor their blood pressure regularly, experts advise.
Women who experience RLS symptoms frequently may be up to 41% more likely to also have hypertension than women without the condition, according to a Harvard University study published in the journal Hypertension in October 2011.
The researchers analyzed data from 65,500 female nurses who participated in the Nurses’ Health Study II, one of the largest, longest-lasting studies ever undertaken on women. Their average age was 50.
Bottom line: Although unable to determine the cause, “the results were significant enough to suggest that women who have restless legs syndrome have a higher prevalence of hypertension,” says Salma Batool-Anwar, M.D., M.P.H., of Harvard Medical School and Brigham and Women’s Hospital.
“Future studies are needed to confirm this association,” Batool-Anwar tells Lifescript, adding she already has launched additional projects. However, women with RLS shouldn’t wait for further results. Sometimes treatment for RLS is minor, “as simple as changing the iron” women take, Batool-Anwar advises.
3. Recurrence of Restless Legs Syndrome After Pregnancy
What it’s about: It’s well-established that pregnant women have about five times the risk of getting restless legs syndrome during pregnancy compared with the general population, says Daniel Picchietti, M.D., clinical associate professor at the University of Illinois School of Medicine.
But what researchers recently discovered is that women with RLS during pregnancy may face a higher risk of developing a chronic form of the condition later in life, according to an Italian study published in the medical journal Neurology in December 2010. The women also may face the same RLS symptoms in subsequent pregnancies.
As one of the first long-term studies to assess a connection between RLS in pregnancy future recurrences, it included 207 women, 74 of whom experienced RLS and 133 who didn't. About 24% of the women who had RLS during pregnancy still had it at the end of a follow-up analysis 6-1/2 years later, compared with 8% of women who didn’t have RLS during pregnancy.
Women with RLS during pregnancy were four times more likely to get it later than those who didn’t have it. About two-thirds of the women with RLS during pregnancy also reported experiencing symptoms in subsequent pregnancies, according to the report.
Bottom line: Don’t fret. “In most cases, RLS symptoms are transient and disappear after pregnancy,” Picchietti says.
Still, be aware that there’s a strong risk of it showing up years later, says study author Mauro Manconi, M.D., Ph.D. of Vita-Salute University in Milan, Italy.
4. Restless Legs Syndrome and Fibromyalgia
What it’s about: RLS shares sleep and fatigue symptoms with fibromyalgia, a disorder in which a person has long-term pain and tenderness in the joints, muscles, tendons and other soft tissues.
“It can be difficult to distinguish fibromyalgia symptoms from RLS symptoms,” says Theodore Omachi, M.D., assistant professor of medicine at the University of California: San Francisco School of Medicine. That's because the two often go hand in hand.
In fact, adults with fibromyalgia are 11 times more likely than those without the disorder to have RLS, and 33% of those with fibromyalgia also have RLS, according to a new study.
What’s the connection? Sleep disruption, which also is a prominent fibromyalgia symptom.
Fibromyalgia patients with RLS suffered worse sleep problems than those without it, the study reported.
Bottom line: A large portion of sleep disturbance among fibromyalgia patients is caused by RLS, says Nathaniel F. Watson, M.D., associate professor of neurology at the University of Washington in Seattle. The study suggests that treating RLS may help improve the rest of patients with fibromyalgia.
5. Dialysis Patients and Restless Legs Syndrome
What it’s about: Diabetes patients undergoing dialysis often have RLS too.
Researchers at the University of Thessaly, Larissa in Thessaly, Greece, studied patients with dialysis and RLS and compared their quality of life with dialysis patients who didn’t suffer from RLS.
The dialysis group with RLS showed signs of thigh-muscle atrophy, compared with patients without RLS, and their quality-of-life scores including mental health were significantly lower than their non-RLS counterparts, according to the researchers.
Bottom line: The low quality of life reported by dialysis patients with RLS, compared with patients without the disorder, was due primarily to increased depression symptoms and sleep-related issues, the scientists concluded.
The muscle atrophy also was attributed to lack of good, “restorative” rest. “About 30% of end-stage renal-failure patients also have RLS,” says Picchietti, who didn’t participate in the Greek study, but is an RLS expert. “Patients with renal failure and RLS are more likely to discontinue dialysis and die," he says. "They get very despondent over RLS.”
6. Genetic Origins of Restless Legs Syndrome
What it’s about: Until recently, researchers were uncertain what caused RLS. Now a team of scientists from the United States, Canada and Europe has discovered new genetic risk factors for the disorder.
The scientific group, led by Juliane Winkelmann, a professor in the neurology department at Technical University in Munich, Germany, studied about 5,000 RLS patients and 7,280 patients without the disorder.
The researchers uncovered two new genetic mutations that play a role in the development of RLS. A mutation is an event that changes the genetic structure of an organism.
One mutation, called TOX3, involves a gene that helps regulate brain activity. The connection between that mutation and RLS still is uncertain.