The Restless Leg Syndrome
09 Feb 2004
A 25 year old university student from Winnipeg writes, "My legs are driving me crazy. I have the feeling there are thousands of ants marching in them. It’s a creepy-crawling sensation that keeps me from sleeping and it’s affecting my studies, not to mention my social life. What can I do?"
The restless leg syndrome (RLS), as this letter indicates, is not just an old age problem. In fact, it’s a common disorder affecting about 10 per cent of the population, slightly more common in women and tends to increase with age. It also has a genetic component tending to run in families.
People suffering from RLS complain of a persistent, overwhelming and distressing urge to move the legs. This usually begins or worsens during the night. Normally the most stressful time is from midnight to 2 a.m. while the early morning hours tend to be symptom-free.
Feeling compelled to pace the floor during the night isn’t the best way to earn an A at examination time. Nor does it improve one’s social life if you are forced to walk around during a concert or while attending a movie.
One businessman remarked to me, " I’ve had this problem for years. The insomnia is one thing. But the thought of sitting motionless on a plane for hours is more than I can endure".
RLS should not be confused with a condition called "periodic limb movement". People with this condition suffer rhythmic movement of the legs about every 20 to 40 seconds during sleep. The main difference is that people with this disorder sleep well as they move around in bed. Meanwhile their bed partners toss and turn wondering if these movements will ever stop.
The majority of patients with periodic limb movement do not suffer from RLS. But often those with RLS suffer from periodic limb movement.
So why do some people have an incessant urge to move their legs? Most experts believe the trouble lies in the brain, rather than in the legs. And that the restlessness is related to a decrease in the level of dopamine in the brain.
Dopamine is a neurotransmitter, a chemical that transmits messages from one cell to another in the brain. Normal movement is produced this way.
Researchers have been aware of the importance of dopamine for years. For instance, patients suffering from Parkinson’s Disease have decreased levels of dopamine, resulting in the inability to control limb movement. But fortunately, RLS is not related to this serious disease.
Recent research has also implicated low levels of iron in regions of the brain that produce dopamine. Since iron is required for the production of dopamine an iron deficiency may in turn lead to the lack of this chemical.
So what can this student and others do to ease restive legs other than pacing the bedroom? Much depends on the severity of the problem. Some people are helped by taking a hot bath or exercising on a stationary bicycle prior to bedtime. Others find relief by stretching calf muscles throughout the day. Or obtain relief by practicing yoga or biofeedback muscle relaxation. But for severe cases medication is needed.
Vitamin E is helpful in a small number of cases. In the past quinine, was prescribed with some success, but serious side-effects, including death, has been associated with its use.
Dr. Christopher Earley, a neurologist at Johns Hopkins Center for Restless Leg Syndrome, says that 99 per cent of patients can be helped by drugs that mimic dopamine’s action in the brain such as Mirapex. But this medication can lose its effectiveness over time.
He also advocates the use of oral iron supplements if blood studies show that iron stores are low. But iron supplements must always be taken on the advice of a doctor. Too much iron can result in iron overload, causing damage to liver and heart.
In one study Dr. Earley administered intravenous iron to RLS patients to increase iron levels in the brain. 75 per cent responded well to a single dose and one patient remained free of RLS for two years. But more research is needed before this treatment is recommended.
