Restless legs syndrome in patients with chronic renal failure on hemodialysis: Does peripheral iron status matter?

Abstract

BACKGROUND: Scant information is available on the prevalence of restless legs syndrome (RLS) among patients with chronic kidney disease (CKD) on hemodialysis and its correlation with peripheral iron status. This study was carried out to estimate the prevalence of RLS among patients with chronic renal failure on hemodialysis and to correlate the presence of RLS with peripheral iron status. METHODS: Adults diagnosed with CKD were studied. Demographic details, comorbid illness, and the number of years diagnosed with CKD and on dialysis were noted. RLS was diagnosed based on the International RLS Study Group criteria. Severity of RLS was assessed by international restless legs scale (IRLS) severity score. The presence of RLS was correlated with peripheral iron status. RESULTS: The mean age of 116 subjects was 50.7±13.6 years. Of the total subjects, 79 (68.1%) were men. The mean body mass index of the subjects was 22.02±3.5kg/m2. The subjects had CKD for a mean duration of 3.5±3.2 years and were dialyzed for 2.5±2.3 years. The prevalence of RLS was found to be 10.3% (12/116). Five subjects each had mild and moderate RLS by IRLS severity score and two had severe RLS. All 12 patients with RLS were hypertensive. Hemoglobin and serum ferritin levels were higher in patients with RLS as compared to those who were RLS negative with CKD. CONCLUSION: RLS was previously undiagnosed in this population. Considering RLS, peripheral iron measures are of questionable validity in patients on hemodialysis. Measures to early diagnosis and prompt treatment should be taken, as RLS is known to cause impairment of daytime functioning, disturbed sleep, and increased mortality.

Keywords

• chronic kidney disease
• peripheral iron status
• restless legs syndrome
• serum ferritin