Stilling Restless Legs A Tailored Approach - Maybe Enhancing Iron - Is Likely Way to Go
One of the best things to happen to Louise Rowles was her husband's
sleep apnea. While visiting a Hopkins sleep clinic, he asked his
clinician, "Could you also help my wife? She walks around all night
because she's got to move her legs."
Neurologist Earley checks up on patient Rowles.
From middle age on, Rowles, 75, had endured restless legs
syndrome (RLS) without proper treatment. Continually misdiagnosed-"There
was always the subtle suggestion that my problem was all in my head," she
says-she'd pad around her house until before dawn, when the sensation
would ebb and she could sleep.
"Many physicians aren't well-versed
in RLS," says Christopher Earley, M.D.
Ph.D., who, with Richard Allen,
Ph.D., heads the Johns
Hopkins Center for Restless Legs Syndrome. The problem may lie in
diagnosis. As Rowles experienced, there's an uncomfortable, not-painful
sensation, most commonly in the foot or leg. Patients describe it as an
aching or "creepy- crawly" sensation or as increasing tension.
The
driving force behind the feeling, however, Earley says, "is the ungodly
urge to move-the perception that sitting still would drive you crazy."
This akathisia vanishes when patients walk about but typically returns
when they're still. Most patients experience secondary movements:
repetitive jerks of the legs or whole body that appear during
rest.
But more typically, says Earley, it's the therapy that's
outdated. Because RLS disrupts sleep, the traditional approach has been
with soporifics like the benzodiazepines. "They're still useful," he says,
"mostly for those with mild symptoms."
He and Allen, however, offer
patients a tailored protocol that may also include opiates,
anticonvulsants or agents to increase or mimic activity of the
neurotransmitter dopamine. The latter may help because recent research
suggests RLS is largely a disorder of the substantia nigra and other
specific subcortical brain regions normally rich in
it.
"Dopaminergic drugs help almost every patient," says Earley.
Rowles, for example, is convinced that dopamine-stimulating Pergolide
changed her life. She recently took an 18-hour flight she "wouldn't have
even considered" before. "But," says Earley, "the drugs must be carefully
prescribed, to avoid symptom-augmenting that may appear."
No cure
exists for RLS. But the future may hold one based, surprisingly, on iron
availability in the brain. Earley's studies on cerebrospinal fluid and
brain tissue show RLS patients have lowered iron that may or may not
reflect what clinicians see in the bloodstream with standard diagnostic
measures. His autopsies confirm low iron levels in brain regions rich in
dopaminergic nerves.
"We assume there's some tie between dopamine
and brain iron metabolism," says Earley. "We just haven't mapped it yet."
For example, IV infusions of iron quickly still patients' restless legs,
but that treatment has safety drawbacks. Meanwhile, Earley says,
clinicians who suspect RLS should test patients for decreased iron stores,
even if they're not anemic. For more information,
call 410.550.1044.
