Early childhood‐onset restless legs syndrome: symptoms and effect of oral iron treatment

Abstract

AIM: To describe symptoms of restless legs syndrome (RLS) in early childhood and the effect of oral iron treatment. METHODS: A study population comprising 22 children, 15 males and seven females referred for paediatric evaluation because of sleep disturbances. Presence of RLS was evaluated using the International RLS Study Group consensus criteria of RLS. In case of ferritin level below 50 ng/mL, oral iron treatment was initiated. Fourteen were examined by polysomnography as well, and periodic limb movement index during sleep (PLMSI) was calculated. Relief of symptoms was recorded by the parents and correlated with ferritin levels and PLMSI. RESULTS: Median age at onset of symptoms was 7.5 months (0-40 months). The most striking single symptom was awakening after 1-3 h of sleep followed by screaming, crying, kicking or hitting the legs. Oral iron supplementation had a positive ferritin-concentration-dependent clinical effect. A relation between high PLMSI and low ferritin levels was demonstrated. CONCLUSION: Symptoms of RLS may start as early as the first year of life, are accompanied by low ferritin levels and a high PLMSI and can be ameliorated by iron supplementation. An increased awareness and knowledge of RLS in early childhood are warranted.