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
