RESTLESS LEG SYNDROME

              Restless Legs Syndrom            

 Restless Legs Syndrom

(RLS) is a disorder of the part of the nervous system that affects the legs and causes an urge to move them. Because it usually interferes with sleep, it also is considered a sleep disorder.

Restless leg syndrome raises mortality risk

In an analysis of 18,425 men participating in the Health Professionals Follow-up Study, men with RLS had a 39% higher mortality risk after adjustment for ageMoreover, the risk remained elevated (30%) after adjustment for lifestyle habits, sleep duration, ethnicity, body mass index, the presence of various chronic conditions, and the existence of other sleep-related disorders. Finally, when the investigators used data only from relatively healthy men (ie, those without major chronic conditions), mortality risk was 92% higher in men with RLS than in controls.

The association between RLS and mortality in the study appeared to be related primarily to respiratory, endocrine, nutrition/metabolic, and immunity diseases, as well as to diseases of the blood and blood-forming organs

Signs and symptoms

Specific DSM-5 criteria for RLS are as follow:

·        An urge to move the legs that is usually accompanied by or occurs in response to uncomfortable and unpleasant sensations in the legs, characterized by all of the following: (1) the urge to move the legs begins or worsens during periods of rest or inactivity; (2) the urge is partially or totally relieved by movement; and (3) the urge to move legs is worse in the evening or at night than during the day or occurs only in the evening or at night

·        Symptoms occur at least 3 times per week and have persisted for at least 3 months

·        Symptoms cause significant distress or impairment in social, occupational, educational, academic, behavioral or other areas of functioning

·        The symptoms cannot be attributed to another mental disorder or medical condition (e.g., leg edema, arthritis, leg cramps) or behavioral condition (e.g. positional discomfort, habitual foot tapping)

·        The disturbance cannot be explained by the effects of a drug of abuse or medication

Approximately 85% of patients with RLS have periodic movements of sleep, usually involving the legs (periodic leg movements of sleep [PLMS]) PLMS is characterized by involuntary, forceful dorsiflexion of the foot lasting 0.5-5 seconds and occurring every 20-40 seconds throughout sleep.

Other features commonly associated with RLS but not required for diagnosis include the following:

·        Sleep disturbances

·        Daytime fatigue

·        Involuntary, repetitive, periodic, jerking limb movements: Either during sleep or while awake and at rest

.

Diagnosis

All patients with symptoms of RLS should be tested for iron deficiency. At a minimum, a ferritin level should be obtained, although a complete iron panel, including the following, is preferable, since ferritin can be falsely elevated in acute inflammatory states:

·        Iron levels

·        Ferritin

·        Transferrin saturation

·        Total iron binding capacity

If a secondary cause of RLS is suspected on the basis of history, abnormal findings on neurologic examination, or poor response to treatment, other laboratory tests should be done. These include a complete blood count (CBC) and measurement of levels of the following:

·        Blood urea nitrogen (BUN)

·        Creatinine

·        Fasting blood glucose

·        Magnesium

·        Thyroid-stimulating hormone (TSH)

·        Vitamin B-12

·        Folate

Other studies include the following:

·        Needle electromyography and nerve conduction studies: Should be considered if polyneuropathy or radiculopathy is suspected on clinical grounds, even if the results of the neurologic examination are apparently normal^[7]

·        Polysomnography: May be necessary to quantify PLMS or to characterize sleep architecture, especially in children and in patients who continue to have significant sleep disturbances despite relief of RLS symptoms with treatment

 .

Management

Pharmacologic therapy

Drug therapy for primary RLS is largely symptomatic, since cure is possible only in secondary disease. Medications used in the treatment of RLS include the following:

·        Dopaminergic agents

·        Benzodiazepines

·        Opioids

·        Anticonvulsants

·        Presynaptic alpha2-adrenergic agonists

·        Iron salt

Nonpharmacologic treatment

·        Sleep hygiene measures

·        Avoidance of caffeine, alcohol, and nicotine in patients with mild RLS who are sensitive to these substances

·        Discontinuation, when possible, of medications that cause or exacerbate RLS, such as selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinepherine reuptake inhibitors (SNRIs), diphenhydramine, and dopamine antagonists

·        Exercise

·        Physical modalities before bedtime, such as a hot or cold bath, whirlpool bath, limb massage, and vibratory or electrical stimulation of the feet and toes