Got restless legs? You could need a dose of iron

COMPA RED with serious illnesses such as cancer and heart disease, restless legs syndrome (RLS) may sound relatively innocuous. But this surprisingly common condition — which affects an estimated three million people in Britain — can have far-reaching health consequences.

It causes symptoms such as leg pain and a ‘creepy crawly’ feeling at the bottom of the legs and feet, typically at night. Most of those affected also experience limbjerking during sleep.

In some cases, the same restless feelings can spread to the arms, torso and even the head.

Yet until recently the only treatments were powerful prescription medicines that can cause serious side-effects.

But this is changing. Just last week came news of a new device strapped around the foot that was shown to improve symptoms for 90 per cent of patients in tests.

If further tests confirm this, it will be a welcome development for a condition that — while in mild cases can disrupt sleep, causing drowsiness and concentration problems during the day — can have serious implications for health. Studies in recent months have found patients with restless legs syndrome are more likely to have high blood pressure — putting them at increased risk of heart attack or strokes — or type 2 diabetes.

Other research has found that a third of those who become depressed because of the impact on their lives have contemplated suicide.

Professor Kailash Bhatia, an expert in RLS at the Institute of Neurology in London, says few people, including many GPs, fully appreciate the impact it can have.

‘Some can become suicidal. They tend to be the ones who don’t respond to medication, and we don’t know why some respond and others don’t.’

Until recently, scientists have had little idea about the cause.

What’s known is that it can run in families, and the most popular theory is that RLS is due to depleted levels of the brain chemical dopamine, which controls muscle activity and movement.

It’s not known why dopamine levels should decline, but everyone’s levels are known to tail off towards the end of the day. If the brain is already producing less of the chemical, this would explain why symptoms often peak in the evening.

Dopamine- boosting drugs, such as levodopa, also used to treat Parkinson’s disease, are often prescribed to block severe symptoms but can have sideeffects such as nausea, constipation and extreme drowsiness.

Those with milder symptoms may be given iron supplements.

Studies show that depleted iron levels in the blood can trigger the symptoms of RLS, probably because iron helps dopamine transmit messages from the brain to the nerves.

This explains why one in five pregnant women or those with very heavy periods are prone to RLS, and may be part of the reason why women are more susceptible than men.

Iron is stored in tissue by the protein ferritin. If its levels in the blood are low — below 50 microgrammes per litre — doctors will often prescribe a small daily iron supplement.

If they are much lower, larger intravenous doses of liquid iron may be needed.

‘ I’d advise people to get their ferritin levels tested before taking an over-the-counter iron supplement,’ says Dr Martin Lee, a consultant neurologist at the Norfolk and Norwich Hospital.

‘It can cause unpleasant sideeffects such as constipation.’

Last week’s announcement about the £260 Restiffic wrap device which is strapped around the foot was significant because it is drug-free.

It applies constant pressure to muscles in the foot to relax them, and signals the brain to relax the leg muscles.

In a trial of 30 people, 27 reported fewer symptoms and better sleep, says the Journal of the American Osteopathic Association.

AS WELL as treatments, experts say there is also an urgent need for better awareness. The charity RLS UK says many live with the condition for ten to 20 years before it is correctly diagnosed. ‘ It often gets mistaken for arthritis,’ says Dr Lee.

‘Patients I see for the first time are often in their 40s or 50s, but have had restless legs since their teens. Some drink huge amounts of whisky to try to get to sleep. Others have lost jobs because of the effect on their concentration.’

Some experts believe that those affected should have regular health checks.

A major U.S. study, published in the Journal of Sleep Research, found the rate of strokes and heart attacks was four times higher in men with restless legs than a healthy group.

Another study from Gdansk University in Poland found nighttime blood pressure readings spiked if patients had RLS.

Dr Lee agrees that regular checks for people with RLS could be worthwhile, as he says it’s ‘highly likely’ that it plays a role in heart disease.

This is because it causes poor sleep, which can trigger increased heart rate, higher blood pressure and a surge in levels of stress hormone cortisol, which is known to raise heart disease risk.