Between 5 and 10% of the population has restless legs. Although the exact cause is unknown, it seems to be clear that RLS does not have the same background in everyone. As a result, there may be differences in how the condition manifests itself and what benefits a patient. These differences are undoubtedly also related to the distinction between primary and secondary RLS. In most people no identifiable cause is found.
In stories of fellow sufferers I have already seen many examples of “remedies” that worked with one person, but seemed to have no effect on the other. I put remedies in quotation marks, because there are actually no means or therapies that completely eliminate the complaints of restless leg syndrome. At most, you can try to ease the symptoms.
Primary RLS is a hereditary issue in more than half of cases. This means that more people in the same family suffer from restless legs. If one person has restless leg syndrome, family members are three to six times more likely to get the disease as well. Much research is currently being done in this regard on characteristics of consanguinity. Members of the same family who have to deal with restless legs may have a hereditary predisposition. In that case they probably share a common piece of DNA.
Two subgroups can be distinguished in primary RLS:
1. People who suffer from restless legs before the age of 45.
2. People who show the first symptoms of RLS after the age of 45.
Heredity plays a role in most cases before the age of 45. If you experience restless legs after the age of 45, this is usually not the case.
Symptoms of primary RLS often do not appear for the first time until middle age. However, research shows that for many of those patients there were indications of restless legs as early as childhood. These signals may not have been recognized as such at the time, but described as growing pains or hyperactivity, for example.
Primary RLS is also referred to as idiopathic RLS. Idiopathic means own disease, so a disease for which there is no identifiable cause. This is when the restless legs do not run in your family and there is no other underlying disease.
In secondary RLS, restless legs are the result of another condition or you are deficient in something. Examples of such another condition are:
• Parkinson’s disease
• Renal impairment
• Thyroid problems
• Rheumatic diseases
• Huntington’s disease
Pregnancy is also an external condition that can involve secondary RLS. People with diabetes, MS, cardiovascular disease, COPD, peripheral neuropathy or anemia are also more vulnerable to troubled legs.
Examples of a shortage are:
• Iron deficiency
• Dopamine deficiency
• Folate deficiency (during pregnancy)
Restless legs may also develop or worsen in some cases with certain medicines. Examples of these drugs are antidepressants, antipsychotics, cold medications and remedies for allergies or nausea. Furthermore, smoking does not promote RLS. Alcohol, coffee, obesity and too little exercise are also unfavorable.