FROM THE EXPERT | Understanding Restless Legs Syndrome

One of the most frequent health problems that I diagnose at Bothwell Sleep Center is Restless Legs Syndrome (RLS). RLS affects over 10% of adults and 2-4% of children, yet few people come in complaining about their legs. When I ask patients sitting down next to me why they are moving their legs back and forth rapidly, they attribute it to nerves or to attention deficit disorder. Often restless legs are not bothersome to the patient but are to the people around them. I will use this column to discuss the under-recognized, and often misunderstood health problem of Restless Legs Syndrome.

Restless Legs Syndrome is an urge to move your legs. It is worse in the evening, worse when sitting or lying down, and better with walking around. While it is called “Restless Legs Syndrome,” it really should be called “Restless Limb Syndrome” as arms can be impacted as well. It is not the same as neuropathy, which causes numbness and burning as opposed to the urge to move the legs. It is also different from nocturnal leg cramps, which are muscle aches in the legs at night.

Underlying medical disorders such as chronic kidney disease and Parkinson ’s disease can be a cause of restless legs. Untreated sleep disorders, lack of sleep, and some medications used to treat depression can also exacerbate Restless Legs Syndrome. One of the least recognized causes of RLS is iron deficiency. Iron is necessary for the production of dopamine, and when brain dopamine levels are low, people may start to sway their legs. When I see patients in the clinic, they often believe that iron deficiency has already been ruled out as a cause of their fatigue. What they may not realize is that iron studies are not a part of a routine blood work up, and that you can be anemic without being iron deficient and iron deficient without being anemic.

Because iron deficiency is a common and treatable cause of RLS, I will have my patients get their blood drawn for serum ferritin and iron levels. If their iron levels are low, I will often start ferrous sulfate 325 mg daily and have them take this medication with orange juice or Vitamin C tablets to help with the absorption of the iron. Unfortunately, ferrous sulfate can darken your stool and cause constipation, so some patients cannot take this over-the-counter mineral. If that is the case, I will make a referral to Bothwell Infusion & Procedure Center for IV iron dextran, which can bring up iron levels much more quickly. In fact, a few days after the infusion, many patients may notice an improvement in their energy level as well as their RLS.

There are many treatments with varying degrees of evidence for the treatment of restless legs. Some patients have claimed that putting a bar of soap under their sheets has helped with their RLS symptoms, but no studies have supported this. Neurontin, which is frequently prescribed to treat neuropathy, is often helpful. Unfortunately, Neurontin often causes sleepiness and weight gain. Medications used in the treatment of Parkinson’s disease such as Mirapex and Requip have historically been used with success in RLS, but they can make symptoms worse over time and should also be used with caution.

If you are having problems with Restless Legs Syndrome or any other sleep disorder, I would be happy to see you in the sleep clinic.

Dr. David Kuhlmann has been Bothwell Regional Health Center’s sleep medicine specialist for 17 years. He is board certified by the American Board of Sleep Medicine and currently serves on the board for the American Academy of Sleep Medicine. He can be reached by calling Bothwell Sleep Center at 660-827-9573.