Symptom Persistence after Iron Normalization in Women with Restless Legs Syndrome

ABSTRACT

OBJECTIVE: The aim of this study was to determine the clinical course of restless legs syndrome (RLS) and potential risk factors for the persistence of RLS symptoms after iron normalization in women with RLS and low serum ferritin (<50 μg/L). METHODS: We reviewed 39 women with RLS and iron deficiency, who achieved iron normalization after oral iron replacement for three months. Risk factors contributing to symptom persistence were estimated by logistic regression analyses. Remission was defined as no RLS symptoms for at least 6 months after the iron normalization. RESULTS: Over the observation period of 2.5±1.4 years, 15 patients reported no RLS symptom whereas 24 patients still complained of RLS symptoms. The remission rate of RLS with iron replacement was 38.5%. The relative risk of symptom persistence was increased by the duration of RLS symptoms (OR 1.88, 95% CI 1.01–3.49) or by the age at RLS diagnosis (OR 1.25, 95% CI 1.01–1.56). CONCLUSION: Almost two-third of RLS patients with iron deficiency showed persistence of the symptom even after iron normalization. Considering that longer duration of RLS symptoms and older age at RLS diagnosis were risk factors for symptom persistence, early intervention of iron deficiency in RLS is warranted.