What are the DSM diagnostic criteria and treatment options for Restless Legs Syndrome (RLS)?

Diagnostic Criteria for Restless Legs Syndrome (RLS)

The diagnosis of Restless Legs Syndrome (RLS) requires meeting all five essential criteria established by the International Restless Legs Syndrome Study Group (IRLSSG), with careful attention to excluding RLS mimics that can lead to misdiagnosis. 1

Essential Diagnostic Criteria (All Must Be Met)

1. An urge to move the legs usually but not always accompanied by or felt to be caused by uncomfortable and unpleasant sensations in the legs

   • Note: Sometimes the urge to move exists without uncomfortable sensations
   • Note: Sometimes arms or other body parts may be involved in addition to legs

2. Symptoms begin or worsen during periods of rest or inactivity such as lying down or sitting

3. Symptoms are partially or totally relieved by movement such as walking or stretching, at least as long as the activity continues

   • Note: When symptoms are very severe, relief by activity may not be noticeable but must have been previously present

4. Symptoms occur or worsen in the evening or night compared to during the day

   • Note: When symptoms are very severe, the worsening in the evening/night may not be noticeable but must have been previously present

5. The symptoms are not solely accounted for as primary to another medical or behavioral condition (e.g., myalgia, venous stasis, leg edema, arthritis, leg cramps, positional discomfort, habitual foot tapping)

   • This criterion is critical for accurate diagnosis, as 16% of subjects without RLS may be misdiagnosed if mimics are not properly excluded 1

Clinical Significance Specifier

The symptoms of RLS cause significant distress or impairment in:

• Social, occupational, educational or other important areas of functioning
• Impact on sleep, energy/vitality, daily activities, behavior, cognition, or mood

Clinical Course Specifiers

• Chronic-persistent RLS: Symptoms when untreated would occur on average at least twice weekly for the past year
• Intermittent RLS: Symptoms when untreated would occur on average less than twice weekly for the past year, with at least 5 lifetime events

Important Diagnostic Considerations

RLS Mimics to Rule Out

Careful differential diagnosis is essential as several conditions can mimic RLS by meeting criteria 1-4 1:

• Leg cramps
• Venous stasis
• Leg edema
• Arthritis
• Positional discomfort
• Muscle aches
• Habitual foot tapping

Special Populations

• Children: Description of symptoms should be in the child's own words; clinical course criteria do not apply 1
• Pregnancy-related RLS: Clinical course criteria may not apply as symptoms may be limited to duration of pregnancy 1
• Drug-induced RLS: Clinical course criteria may not apply as symptoms may be limited to medication use 1

Treatment Options for RLS

For moderate to severe RLS, dopamine agonists are the first-line treatment, particularly pramipexole, ropinirole, and rotigotine 2. The FDA has specifically approved ropinirole for moderate-to-severe primary RLS 3.

Treatment algorithm based on severity:

1. Mild or intermittent RLS:

   • Low doses of L-DOPA or codeine 2

2. Moderate to severe RLS:

   • First-line: Dopamine agonists (pramipexole, ropinirole, rotigotine) 2
   • Ropinirole dosing: Start at 0.25 mg once daily 1-3 hours before bedtime, titrate based on response over 7 weeks to maximum 4 mg daily 3

3. Severe, refractory or neuropathy-associated RLS:

   • Antiepileptic drugs (gabapentin, pregabalin) 2
   • Opioids (oxycodone, tramadol) 2

4. RLS with iron deficiency:

   • Iron supplementation is essential 2, 4
   • May reduce risk of augmentation with dopaminergic therapy 4

Treatment Complications

• Augmentation: Paradoxical worsening of symptoms with dopaminergic treatment is the main challenge in difficult-to-treat patients 4
  • Symptoms may begin earlier in the day
  • May require switching medications or adjusting dosing schedule

Clinical Pearls

• RLS affects approximately 2-10% of the general population 2, 5
• Women are affected approximately twice as often as men 5
• Most patients with RLS also have periodic limb movements during sleep, though this is not part of the diagnostic criteria 5
• The International RLS Rating Scale (IRLS) is a recommended tool for assessing severity 1, 3
• RLS may be primary (idiopathic) or secondary to conditions like iron deficiency, renal failure, pregnancy, or peripheral neuropathy 2, 4

Remember that proper diagnosis requires careful exclusion of RLS mimics, as misdiagnosis is common when relying solely on the first four criteria without proper differential diagnosis.