More than two million people in Spain may be living with restless legs syndrome without knowing what is causing their symptoms. The Spanish Society of Neurology says up to 90% of cases could remain undiagnosed. Diagnosis can take more than ten years. The delay is especially serious when the disorder begins in childhood, since its signs can be mistaken for growing pains or ADHD.
Restless legs syndrome involves more than an urge to move. It can cause tingling or itching, pain and other discomfort in the legs. These sensations appear or worsen during inactivity and ease temporarily with movement. Symptoms usually intensify in the afternoon and at night, making it harder to fall asleep and get restorative rest.
Recent Spanish reports by La Razón and El Mundo estimate that restless legs syndrome affects about 11.6% of the population, while more severe forms account for roughly 2% to 3% of cases.
The condition can disrupt ordinary activities well before bedtime.
Up to 60% of affected people have trouble sitting still or relaxing. The syndrome often causes insomnia and poor sleep quality, while some medicines may worsen its symptoms. Patients can end up repeatedly treating the effects of lost sleep without addressing the neurological disorder behind them. Diario Vasco has also reported that diagnosis is generally clinical. Doctors may order tests, including assessments of iron levels or kidney function, when investigating an underlying cause.
The SEN estimates that SPI affects up to 10% of adults and nearly 4% of children and adolescents. Women are affected approximately twice as often as men. Low iron levels and metabolic changes matter particularly during pregnancy and periods of heavy menstruation, although iron deficiency does not explain every case. A regional report by Heraldo put the number of potentially affected people in Aragón at about 55,000, illustrating the scale of the problem beyond national estimates.
Specialists quoted by Spanish sleep-medicine sources, including the Spanish Society of Sleep, warn that the burden extends beyond insomnia. Persistent restless legs symptoms have been associated with suicidal behaviour and a higher risk of depression and anxiety. Timely recognition matters for sleep quality and broader mental health follow-up.
Pregnancy can bring on the disorder in women who had no previous symptoms. Between 11% and 30% of such women may develop SPI during gestation, especially in the third trimester. Family history is also common: around 65% of people with the syndrome have relatives with the condition. Chronic kidney failure and diabetes, along with certain neuropathies, have also been associated with it.
The diagnostic challenge affects every age group, but symptoms can look different. In children, early signs may be confused with normal growth-related discomfort or ADHD. In adults, they can be blamed on rheumatic diseases or circulatory problems. Some patients and clinicians may initially label them as ordinary insomnia or anxiety. This gap in diagnosis deserves the same sustained attention given to other neurological conditions in earlier health reporting.
Dr Celia García Malo of the SEN's Study Group on Wakefulness and Sleep Disorders says the first step is to look for a possible underlying cause. Neurological follow-up is then needed so treatment can be adjusted as the patient's stage and needs change. The SEN's position is practical: shorter delays can reduce inappropriate treatment and allow a better approach to begin sooner.
Treatment guidance is also changing. The SEN is updating its SPI recommendations following a large change by the American Academy of Sleep Medicine in 2024. The new approach moves away from routine long-term use of dopaminergic medicines and prioritises checking and correcting iron levels alongside other treatment options.
That change matters because SPI is a chronic disorder. Medication can cause adverse effects if treatment is not reviewed over time. For Spain, the priority is to recognise the pattern earlier and investigate possible causes, with neurological follow-up continuing over time. Years of sleep disruption should not pass without a diagnosis. A condition affecting millions should not remain hidden behind labels such as poor circulation, growing pains or ordinary insomnia.
