Restless Leg Syndrome (RLS) is a neurological (nervous system) disorder. It is characterized by an urge to move the legs in order to relieve abnormal sensations such as pain, creeping, or burning. In fact, some people say it feels like insects are crawling around inside their legs.
The urge to move the legs occurs during periods of rest, such as before falling asleep, and generally tends to be worse in the evenings and at night. Although movement relieves the symptoms, the sensations often return. Although this condition is known as Restless Leg Syndrome, the abnormal sensations can occur in the arms as well.
According to the age of onset, RLS is categorized as early-onset or late-onset.
Early-onset RLS starts before the age of 45 years, tends to run in the family and evolve slowly with a female to male ratio of 2 to 1.
Late-onset RLS starts after the age of 45, is as common in both genders, evolves more quickly, and is more severe. There is no familial tendency but there is a common association with nerve disease and spinal cord disease.
Sometimes, people with RLS also experience sudden jerking of the arms and legs known as periodic limb movements. People don't have control over this movement, which generally occurs every 20 to 60 seconds and may continue throughout the night.
From 2% to 15% of people around the world may have RLS.
The cause of RLS is not clear. Scientists have observed that approximately half of the people who have RLS also have a family member with the condition.
RLS is thought to be caused by one of the following underlying conditions:
- low levels of iron or certain vitamins
- kidney failure
- Parkinson's disease
- other diseases of the nervous system
- medications used to treat nausea, seizures, depression, or psychosis
People with these conditions sometimes experience relief from RLS symptoms once the underlying condition is treated or when the suspected drug is discontinued.
Drinking coffee or alcohol and smoking may aggravate or trigger symptoms in people with RLS or those who are likely to develop it. Decreasing your intake of these substances, or stopping them altogether, may relieve or reduce symptoms of RLS. Not getting enough sleep also seems to aggravate the disorder.