Restless legs syndrome

Disease Description (Causes and Symptoms)

• Definition summary: A neurological disorder characterized by uncomfortable sensations occurring mainly in the legs during rest (while sitting or lying down)—such as crawling, a feeling of insects crawling, pulling, or tingling—and an urge to move as a result. It worsens especially in the evening and at night, causing sleep disturbances.
• Main causes and pathophysiology: The exact cause is unknown, but it is presumed to be associated with abnormalities in the central dopaminergic system. Iron (Fe) deficiency related to dopamine metabolism may be a triggering factor. It is associated with peripheral neuropathy, chronic kidney disease, diabetes, anemia, and pregnancy (especially late pregnancy).
• Main symptoms: Unpleasant sensations in the legs (crawling, pulling, tingling, pain), worsening during rest, relief with movement, and worsening at night and in the evening. Symptoms may extend to the arms, shoulders, and other areas.
• Diagnostic points (clinical diagnosis): All 5 of the following must be met
  1. A strong urge to move the legs (often accompanied by unpleasant sensations)
  2. Worsening of symptoms during rest (in a sitting or lying position)
  3. Relief of symptoms with movement (such as walking)
  4. Symptoms begin or worsen in the evening or at night
  5. Symptoms are not explained solely by another disease
• Additional evaluation: If necessary, polysomnography (when another sleep disorder is suspected), blood tests (ferritin and iron, CBC, kidney function, blood glucose, thyroid function), and a neurological examination.

Treatment Methods

• Treatment principles: Depending on the frequency and severity of symptoms and whether sleep disturbances are present, non-drug therapy is prioritized or combined with drug treatment. Treatment of underlying conditions (iron deficiency, kidney disease, diabetes, etc.) is essential.
• Non-drug therapy (mild cases and supportive therapy)
  • Maintain regular sleep habits (keep consistent sleep and wake times)
  • Limit caffeine, smoking, and excessive alcohol consumption; manage stress and fatigue
  • Leg massage, foot baths, light stretching and exercise (avoid vigorous exercise immediately before rest)
  • Keep warm (symptoms may improve when the legs are warm)
• Drug treatment (for moderate or more severe cases or when sleep disturbances are present)
  • Dopamine agonists (first-line medications used in clinical practice): pramipexole, ropinirole, etc. — effective, but long-term use may cause adverse effects such as augmentation (worsening of symptoms) and impulse-control disorders
  • α2δ ligands (antiepileptic drug class): gabapentin enacarbil, gabapentin, pregabalin — used especially when pain-type symptoms or sleep disturbances are present
  • Iron supplementation: If serum ferritin is low (generally, supplementation may be considered when ferritin is <50–75 ng/mL), oral or, if necessary, intravenous administration
  • Other treatments (refractory or special cases): opioids (low dose), benzodiazepines (sleep aids, e.g., clonazepam) — caution is required regarding long-term use and dependence
• Procedures/surgery: Not applicable (mainly treated with drug and non-drug therapies)
• Precautions and risk of complications
  • With long-term use of dopamine agonists, monitoring is necessary for augmentation (earlier onset and worsening of symptoms over time) and impulse-control disorders (gambling, overeating, etc.)
  • When taking iron supplements, be cautious of gastrointestinal adverse effects and excessive iron (confirm target levels through testing)
  • If left untreated, chronic sleep disturbances may cause daytime fatigue, impaired cognitive function, and depression
• Precautions for self-management
  • Consult a doctor before changing or stopping prescribed treatment
  • Limiting caffeine, nicotine, and alcohol is recommended because they may worsen symptoms
  • Consult a specialist regarding medication use during pregnancy or breastfeeding

Checklist Before an Outpatient Visit (Including Example Questions)

• Items to prepare (recommended to bring)
  • A list of all medications and supplements currently being taken (including doses and dosing times)
  • Previous blood test results (especially ferritin, iron, CBC, kidney function, and blood glucose)
  • A sleep diary (record the times and frequency of symptoms and changes in sleep quality)
  • Photos or videos taken when symptoms occur (such as showing relief through movement)
  • Medical history (diabetes, kidney disease, anemia, peripheral neuropathy, history of sleep apnea), family history, and pregnancy status
• Records that are useful to prepare in advance for the outpatient visit
  • When symptoms began, factors that worsen or improve them, patterns of nighttime worsening, and impact on quality of life (such as daytime sleepiness)
• Example questions for checking suspected symptoms (questions patients can record for themselves)
  • When do the symptoms mainly begin (at what time of day)?
  • Are the symptoms worse during rest? How quickly do they improve when you move?
  • Do they affect your sleep (difficulty falling asleep, awakenings, daytime sleepiness, etc.)?
  • Does anyone in your family have similar symptoms?

General Example Questions to Ask the Doctor

• What are the main adverse effects of this medication (the recommended medication), and how likely are they to occur?
• What problems (e.g., worsening symptoms or impulse-control disorders) may occur with long-term use?
• Based on my blood test results (including ferritin), do I need iron supplementation? What is the target level?
• Which lifestyle habit is most important for me to change?
• Do I need to continue taking the medication even after the symptoms disappear?

Examples of Disease-Specific Questions

• At what ferritin (iron stores) level would you recommend oral or intravenous iron supplementation?
• When starting dopamine agonist treatment, how will you monitor and prevent the risks of augmentation and impulse-control disorders?