How to Diagnose Restless Legs Syndrome: Symptoms, Testing, and Differential Diagnosis
Understanding Restless Legs Syndrome (RLS)
Restless Legs Syndrome (RLS), also known as Willis-Ekbom Disease, is a neurological disorder characterized by an overwhelming urge to move the legs, often accompanied by uncomfortable sensations. These symptoms typically worsen during periods of rest, especially in the evening or at night, significantly disrupting sleep and overall quality of life.
Key Clinical Features for Diagnosis
The diagnosis of RLS primarily relies on clinical evaluation based on five essential criteria established by the International Restless Legs Syndrome Study Group (IRLSSG). These include:
- An urge to move the legs, usually caused by uncomfortable sensations such as tingling, crawling, or pulling.
- Symptoms begin or worsen during inactivity or rest, particularly when sitting or lying down.
- Movement, such as walking or stretching, provides temporary relief.
- Symptoms follow a circadian pattern, becoming more severe in the evening or at night.
- The symptoms are not solely accounted for by another medical or behavioral condition.
Ruling Out Other Conditions
Because several disorders can mimic RLS—such as peripheral neuropathy, venous insufficiency, fibromyalgia, or even habitual leg movements—it's crucial to perform a thorough differential diagnosis. A detailed patient history and physical examination help exclude conditions that may present with similar leg discomfort or movement urges.
Diagnostic Tools and Medical Evaluations
While there is no single definitive test for RLS, healthcare providers may use a combination of assessments to support the diagnosis and rule out underlying causes:
Blood tests are commonly ordered to check for iron deficiency, especially low ferritin levels, which are strongly linked to RLS. Kidney function, glucose levels, and thyroid activity may also be evaluated.
Neurological and electromyography (EMG) studies can help identify nerve or muscle disorders that might cause leg symptoms resembling RLS, such as radiculopathy or myopathy.
In some cases, polysomnography (sleep study) is recommended, particularly if sleep disruption is significant. This test monitors brain waves, oxygen levels, heart rate, and limb movements during sleep, helping to detect periodic limb movements of sleep (PLMS), which frequently occur in RLS patients.
When to Seek Medical Help
If you regularly experience unexplained leg discomfort at night that improves with movement, it may be time to consult a neurologist or sleep specialist. Early diagnosis not only helps manage symptoms effectively but also prevents long-term complications related to chronic sleep deprivation and reduced daytime functioning.
Conclusion
Diagnosing Restless Legs Syndrome involves a careful analysis of symptoms, exclusion of mimicking disorders, and targeted testing to confirm the presence of contributing factors like iron deficiency. With proper evaluation and personalized treatment plans, most individuals with RLS can achieve significant symptom relief and improved sleep quality.