The prevalence and clinical characteristics of restless legs syndrome in patients with iron deficiency anemia in Korea

Abstract

STUDY OBJECTIVES: While the prevalence and clinical characteristics of restless legs syndrome (RLS) are known to vary according to ethnicity, a detailed evaluation of this condition among patients with iron deficiency anemia (IDA) has not yet been reported in an Asian population. We investigated the prevalence and clinical characteristics of RLS in patients with IDA in Korea compared with age- and sex-matched patients diagnosed with idiopathic RLS.

METHODS: This prospective single-center study was performed at a regional university hospital. Consecutive patients with IDA were enrolled over a 4-year period. Clinical interviews and laboratory tests were conducted at the first visit. RLS diagnosis was confirmed through face-to-face interviews. We randomly selected patients with idiopathic RLS without comorbid medical disorders from our sleep center dataset as control patients. The clinical characteristics of both groups were compared.

RESULTS: We enrolled 124 patients with IDA. Fifty (40.3%) patients were diagnosed with RLS, with 82% exhibiting severe to very severe symptoms. Patients with IDA and RLS were older and reported more sleep deterioration than patients with IDA without RLS. Patients with IDA and RLS also had a more depressed mood and higher periodic limb movement index scores than patients with idiopathic RLS.

CONCLUSIONS: The prevalence of RLS among patients with IDA in Korea was high, with the majority having severe to very severe symptoms. Patients with IDA and RLS had poorer sleep quality and more emotional problems than patients with IDA without RLS. Therefore, patients with IDA should be screened for RLS to prevent adverse effects on the quality of sleep and life.