Does RLS Run in the Family?
Willis-Ekbom Syndrome, better known as Restless Leg Syndrome (RLS), affects about five to ten percent of adults and two to four percent of children. Although the disease is not well understood, we do know that it causes an irresistible urge to move the legs to relieve discomfort and pain. But what exactly causes RLS? There are several causes, but for many patients, RLS is genetic.
Causes of Restless Legs
Restless leg syndrome is caused by a lack of the neurotransmitter dopamine in the brain. The substantia nigra, the main area of the brain where dopamine is produced, is part of the basal ganglia. This area of the brain is responsible for the control of voluntary motor movements, among other things. Low dopamine levels in this area can lead to an inability of the brain to inhibit the painful sensations associated with RLS. There are a number of conditions that can cause these low levels of dopamine, and they are called secondary causes.
The most common secondary cause of restless leg syndrome is iron deficiency. Iron is a cofactor in the production of the neurotransmitter dopamine. When iron levels are low, dopamine production is low as well. Interestingly, only about 15 percent of patients with RLS have low serum iron levels, meaning these people have normal levels of iron in their blood, but not in the substantia nigra where dopamine is produced.
Another secondary cause of RLS is varicose veins. Although varicose veins are not related to dopamine levels, they can be painful. This can lead to the uncontrollable urge to move the legs that are so common in people with RLS.
However, about 60 percent of RLS cases are genetic, being passed down through generations and having no secondary cause. Scientists suspect the responsible genes are involved in the development of the neurological system during fetal development. But just because you inherited RLS, doesn’t mean you need to suffer. RLS can be treated successfully.
Treatment for Restless Leg Syndrome
Treatment depends on what is causing the RLS. Once the secondary cause is found, treating it typically alleviates symptoms, and in some cases, RLS permanently subsides. For example, treating someone who has an iron deficiency with iron supplementation will, in most cases, relieve RLS symptoms after taking the iron for several days to weeks.
In patients with varicose veins, treatment of the veins themselves can be successful in relieving symptoms. Endovenous laser and sclerotherapy are common and effective treatments for varicose veins and can provide relief for RLS caused by them.
When it comes to RLS that is inherited, the main course of treatment is medications that increase dopamine levels in the brain such as Mirapex or Requip. These medications are very successful in alleviating symptoms, but in some cases, trial and error with dosage variations are required.