Restless Legs Syndrome (RLS) and Periodic Limb Movement (PLMD) are two disorders that are very similar in their signs and symptoms as well as their treatment. It is very likely, but not always true, if you suffer from one, you may suffer with the other as well. The primary difference is that RLS occurs while awake and PLMD occurs while sleeping.
Restless Legs Syndrome (RLS) is a neurologic sensorimotor disorder that is characterized by an overwhelming urge to move the legs when they are at rest. The urge to move the legs is usually, but not always, accompanied by unpleasant sensations. These sensations keep many people from falling asleep since they constantly want to move their legs. More than 80 percent of people with RLS also suffer from a condition know as periodic limb movements in sleep (PLMS).
RLS symptoms occur during inactivity and they are temporarily relieved by movement or pressure. Symptoms of RLS are most severe in the evening and nighttime hours and can profoundly disrupt a patient’s sleep and daily life.
Symptoms include an urge to move the legs often associated with uncomfortable feeling in the legs (e.g. tingling, creepy, itching, pulling or aching) during periods of inactivity, including both sleep and wakefulness. Symptoms may also include involuntary jerking of the limbs that intensifies in the evening or at night and is relieved by movement. People with RLS tend to have difficulty falling or staying asleep and suffer from chronic sleep loss, leaving them with the tired feelings that occur with sleep loss.
RLS affects approximately 10% of adults in the U.S. Researchers believe that RLS is commonly unrecognized or misdiagnosed as insomnia or other neurological, muscular or orthopedic condition. RLS may also be confused with depression. According to the Restless Legs Syndrome Foundation, approximately 40% of people with RLS complain of symptoms that would indicate depression if assessed without knowledge or consideration of a sleep disorder.
RLS affects both men and women, can start at any age and can run in families. In addition, the severity of the disorder appears to increase with age. Older patients experience symptoms more frequently and for longer periods of time.
The exact cause of RLS is unknown but it has a primary form, not related to other disorders, and a secondary form related to an underlying condition such as kidney failure, pregnancy, or iron deficiency anemia. It may also be caused or made worse by certain medications.
There is no specific diagnostic test for RLS. If you suspect you may have the disorder, talk to your doctor as soon as you can. If possible, bring a diary of your sleep as well as a record of the occurrence and severity of your symptoms with you. Your doctor will conduct tests to rule out factors that may be causing the symptoms such as pregnancy, iron deficiency and end-stage renal failure. You can expect that he or she will ask what time your symptoms occur, when they are most severe, what you were doing before the onset of symptoms, and how much time elapses before you are able to get to sleep due to your RLS. Your doctor will also need a record of your sleep quality and quantity during the time when symptoms appear and whether or not you experienced any pain along with the RLS symptoms.
Until recently, there were no FDA-approved drugs for the treatment of RLS. In May 2005, a drug called Requip® (ropinirole hydrochloride) that is commonly used to treat Parkinson disease was given FDA approval at lower doses for the treatment of moderate-to-severe primary RLS after patients in clinical trials enjoyed more and better quality sleep as early as one week after starting treatment. In 2006, a drug by the name of Mirapex® was also approved by the FDA for the treatment of moderate-to-severe primary RLS. In clinical trials of Mirapex® it was shown that lower doses (than used for Parkinson’s disease) improve RLS symptoms, sleep satisfaction, and quality of life. Both drugs may cause side effects such as nausea and dizziness and may cause patients to fall asleep without any warning, even while doing normal daily activities such as driving.
There are also a number of self-directed activities for managing the symptoms of RLS including walking, massaging the legs, stretching, hot or cold packs, vibration, and acupressure. Practicing relaxation techniques such as meditation or yoga have been known to alleviate symptoms. For many people, treating an underlying cause or effective pharmacological treatment of primary RLS and implementation of coping strategies provides relief from most symptoms. However, sometimes medications need to be changed over time or doses adjusted and regular consultation with a physician is recommended.
Periodic limb movements in sleep are repetitive movements, most typically in the lower limbs, that occur about every 20-40 seconds. If you have PLMS, or sleep with someone who has PLMS (also referred to as PLMD, periodic limb movement disorder), you may recognize these movements as brief muscle twitches, jerking movements or an upward flexing of the feet. They cluster into episodes lasting anywhere from a few minutes to several hours.
In most people with PLMS, poor sleep and daytime sleepiness are the most bothersome symptoms. Many people do not link their sleep problem with leg movements.
Since this happens during sleep, you have to look for other clues that you may suffer from PLMS. You can ask your bed partner if they feel or see you moving around through out the night or look to see if your sheets are always a mess in the morning. Individuals with PLMS may also experience RLS, an irritation or uncomfortable sensation in the calves or thighs, as they attempt to fall asleep or when they awaken during the night. However, research also shows that many individuals have PLMS without experiencing any symptoms at all.
PLMS can occur at any age. Like many sleep disorders, PLMS is more common in middle-aged and older people.
You should talk to your doctor if you think you have this disorder. Your bed partner can speak with your doctor to help give a better description of what happens while you sleep and help answer some questions you may not know the answers to since you are asleep.
An overnight sleep study will show for sure if you have this sleep disorder but many times it can be diagnosed listening to the patient.
A number of medications have been shown to be effective in treating PLMS, but treatment is only necessary when PLMS are accompanied by restless legs (RLS), insomnia or daytime fatigue. If this is the case, medications used to treat RLS will be effective to treat PLMS.