Vol. 16 Issue 22
My Legs Won't Let Me Sleep!
Restless legs syndrome can cause insomnia
That pulling, drawing, tingling, wormy, crawly, just-gotta-move-my-legs feeling might be restless legs syndrome (RLS). As its name implies, individuals with RLS feel an overwhelming urge to move their legs. It's a neurological condition that may begin at any stage of life, but tends to worsen during pregnancy and with aging.
The severity of the symptoms ranges from mild to severe, following a circadian rhythm with symptoms most noticeable at night. Movement of the legs provides temporary relief which disrupts sleep and leaves the person with the disorder sleep-deprived and exhausted.
The diagnostic criteria for RLS were developed in the 1970s by the American Sleep Disorders Association, then further refined in 1995 by The International Restless Legs Syndrome Study Group. The essential criteria that must be present for a diagnosis of RLS include:
1. An urge to move the legs, usually accompanied by an uncomfortable sensation.
2. The urge to move the legs that begins or worsens during inactive sitting or lying.
3. The urge to move the legs that is temporarily relieved by movement, but the relief generally lasts only as long as the activity continues.
4. The urge to move the legs that follows a circadian rhythm–only occurring during the evening and night or, if present during the day, worsening during the evening and night.
Sleep Disorder and RLS
Sleep disorder is often the main reason that individuals will talk to a physician about RLS. Sleep disorder occurs because relief from the urge to move comes from moving or engaging the brain in activity–neither of which is helpful to sleep. The time spent resting before falling asleep is prime-time for RLS. In a mild case of RLS, the symptoms start after a longer period of rest, giving more time to fall asleep before the urge to move begins. The faster an individual with RLS falls asleep the less likely the symptoms will disrupt sleep. In moderate to severe RLS, the symptoms occur after a short period of inactivity and can cause a significant sleep loss.
According to We Move, Worldwide Education and Awareness for Movement Disorders, periodic limb movement disorder (PLMD) affects as many as 85 percent of individuals with RLS and also causes sleep disturbance. Unlike RLS, which disrupts the ability to fall asleep, PLMD causes periodic limb movements in sleep that cause awakening many times during the night. The individual with periodic limb movements is often unaware of waking repetitively during the night, but the changes in sleep are measurable with EEG. As a result, the person with PLMD wakes in the morning feeling tired and unrested.
Pathophysiology of RLS
Studies to find the source of RLS dysfunction have narrowed it to the subcortical areas of the brain. Dopamine agonists have been found to successfully treat RLS pointing to abnormalities in dopaminergic function. There also appears to be decreased inhibition of the sensorimotor cortical system and the spinal system. Primary forms of RLS occur spontaneously, and a family history is reported in many cases, suggesting a genetic component to the disease.
Secondary Forms of RLS
Secondary RLS can occur because of an underlying medical condition. Three secondary reversible forms of RLS, pregnancy, end-stage renal disease, and iron deficiency anemia, are all related to iron insufficiency. RLS may initially appear for some woman during pregnancy and disappear again after pregnancy. RLS in end-stage renal disease will often resolve after renal transplantation. Iron levels are difficult to maintain in both situations.
According to the Restless Legs Syndrome Foundation, two studies have found lower serum levels of ferritin in patients with RLS. Reduced iron in the substantia nigra and putamen were found in one study using MRI studies of patients with RLS and also in an autopsy study. The substantia nigra contains cells of one of the major dopaminergic pathways. Iron deficiency in the brain is an important finding for treatment of patients with RLS. Evaluation and treatment of iron deficiency has been found to improve or resolve RLS symptoms in some patients.
Treatment of RLS
A physician may begin treatment for RLS by evaluating all over-the-counter medications taken by the patient that may be causing symptoms of RLS. Medications that can aggravate RLS include certain drugs that control nausea and cold and allergy medications.
Prescription drugs that can cause symptoms include certain drugs that are used to treat seizures, psychoses and depression. Elimination or replacement of the problem drug is one step that can reduce RLS.
Supplementation with iron as directed by a physician is another effective strategy for RLS patients who are iron deficient. Treatment of deficiencies in folate, magnesium and vitamins B, C or E have also been found to decrease symptoms for some patients.
Medical conditions that may bring on symptoms include uremia, thyroid problems and diabetes mellitus. Control of the underlying medical condition may help to reduce or eliminate the symptoms of RLS.
The following also need to be ruled out as a source of the problem: leg cramps, peripheral neuropathy, varicose veins, intermittent claudication, positional discomfort, pain from arthritis or radiculapathy.
Implications for Rehabilitation Professionals
Sleep is essential to repair and healing of the body. Patients who aren't well rested have difficulty progressing exercise programs and continually present with stress-related muscle pain. Questioning patients about sleeping habits needs to be a basic part of the physical therapy evaluation. When a patient reports unusual sensations in the legs that make falling asleep difficult, a referral to a physician is essential for proper treatment.
We Move, Worldwide Education and Awareness for Movement Disorders, 204 West 84th Street, New York, NY 10024; www.wemove.org; www.mdvu.org
The Restless Legs Syndrome Foundation suggests the following strategies for temporarily relieving the symptoms of RLS:
• Taking a warm bath or shower;
• Using massage or vibration on the affected limb;
• Engaging in mentally stimulating activities such as reading, knitting or playing video games.
Information on RLS
Restless Legs Syndrome Foundation, 819 Second Street, SW, Rochester, MN 55902-2985; www.rls.org