Better Sleep with Restless Legs? Start With Iron

Restless legs syndrome (RLS) causes a strong urge to move the legs when resting, which often interferes with sleep quality.

“The sensation isn’t really painful, but it is an uncomfortable sensation that makes you want to move your leg. It typically gets worse at night, although in extreme cases you see patients start having symptoms all day,” says University Hospitals sleep medicine specialist Eric Yeh, MD.

The condition can occur at any age, but it’s most common in people over 50 and typically gets worse over time. The good news is that RLS is often caused by an iron deficiency and can be treated with iron supplements.

Symptoms of RLS

Restless legs syndrome (RLS) affects up to 10 percent of adults. Symptoms may include:

• Leg discomfort that begins while resting. Unpleasant sensations might feel like pulling, itching, tingling, crawling or tugging.
• Worsening symptoms at night.
• Moving around relieves the sensation.
• Patients may have symptoms several nights a week and or less frequently.

Chronic sleep loss because of RLS can lead to significant physical, psychological and cognitive problems. “The effect of RLS on sleep is very real,” says Dr. Yeh. “It interferes with the ability to fall asleep, to stay asleep and creates fragmentation of sleep, which leads to sleep deprivation.”

Symptoms of RLS may decrease or disappear for a while, but they often reappear and become more severe over time.

What Causes RLS?

The cause of RLS is unknown, but it may be related an imbalance in the brain neurotransmitter dopamine. The disorder tends to run in families, and has been linked to certain gene variants.

Risk factors for RLS include:

• Kidney disease
• Neuropathy
• Multiple sclerosis
• Diabetes
• Rheumatoid arthritis
• Sleep disorders such as sleep apnea
• Pregnancy
• Antidepressant and antihistamine use
• Alcohol and caffeine

Diagnosing RLS

There’s no specific test for RLS. Diagnosis is made with a clinical exam based on symptoms. “There are four diagnostic criteria we asked patients about, and if they answer yes to all of them, we make a clinical diagnosis,” Dr. Yeh says.

A blood test for ferritin – a blood protein that stores iron – is also part of the medical evaluation. Depending on the results, a doctor may recommend iron supplements and/or dietary changes to boost iron.

“Once we address an iron deficiency, in my experience 40 to 50 percent of patients will have their RLS symptoms treated and resolved without medication,” he says.

Treating RLS

New treatment guidelines suggest checking for and treating low iron which can improve symptoms naturally. Doctors also may prescribe gabapentin and pregabalin, which are anticonvulsant drugs.

Commonly used medications for restless legs, called dopamine agonists (like pramipexole and ropinirole), can help at first but often stop working over time. They may even make symptoms worse. “Some people develop tolerance very quickly, and generally people always develop some tolerance. We have known that for a long time, but with recently updated guidelines, now people are paying more attention to it,” Dr. Yeh says.

People should not ignore symptoms of RLS, Dr. Yeh says. Long-term sleep deprivation can increase the risk of cardiovascular disease, type 2 diabetes, and affect mood, memory and immune function.

“People need 7-9 hours of sleep. Sleep deprivation leads to poor health.” Dr. Yeh also recommends that patients avoid common triggers for RLS, including alcohol and caffeine, and look for signs of untreated sleep apnea.