The prevalence and potential aetiological factors associated with restless legs syndrome in patients with chronic kidney disease: a cross-sectional study

Int Urol Nephrol. 2022 Oct;54(10):2599-2607. doi: 10.1007/s11255-022-03166-9. Epub 2022 Mar 11.

Abstract

Background: There is limited understanding of aetiological factors of and treatment options for restless leg syndrome (RLS) in patients with chronic kidney disease (CKD). This study aimed to estimate the prevalence of RLS in CKD patients and identify factors that may contribute to RLS.

Methods: A questionnaire-based cross-sectional study of patients with CKD stage 4 (CKD 4), pre-dialysis stage 5 (CKD-5ND) and haemodialysis-dependent stage 5 (CKD-5D) was conducted. Eligible patients were enrolled from the local dialysis units and renal clinics. The International RLS Study Group rating scale was used to establish the diagnosis of RLS and quantify its severity.

Results: 212 patients with CKD 4 (n = 92), CKD-5ND (n = 14) and CKD-5D (n = 106) were included. The overall prevalence of RLS was 32.1%. Women had a significantly higher odds of having RLS despite adjustment for age, diabetes, cardiovascular disease and whether patients were on dialysis (odds ratio 2.8 [95% confidence intervals 1.5-5.2]). In pre-dialysis groups, patients with RLS had significantly higher serum ferritin (323.9 [SD 338.1] vs 177.5 [SD 178.5] µg/L, p = 0.020) compared to non-RLS patients. In dialysis patients (CKD-5D), those with RLS had significantly higher total white cell (8.0 [SD 3.5] vs 6.8 [SD 1.9] × 109/L, p = 0.026) and neutrophil (6.4 [SD 3.9] vs 4.6 [SD1.7] × 109/L, p = 0.002) counts compared to patients without RLS.

Conclusion: RLS remains a significant problem in patients with CKD and may be related to underlying inflammation. Targeting this pathway may be useful. Prevalence of RLS, diagnosed using validated measures, is higher than previous reports.

Trial registration: N/A (the current study is not a trial).

Keywords: Chronic kidney disease; End-stage renal failure; Haemodialysis; Quality of life; Restless legs syndrome.

MeSH terms

  • Cross-Sectional Studies
  • Female
  • Humans
  • Kidney Failure, Chronic* / complications
  • Kidney Failure, Chronic* / epidemiology
  • Kidney Failure, Chronic* / therapy
  • Prevalence
  • Renal Dialysis / adverse effects
  • Renal Insufficiency, Chronic* / complications
  • Renal Insufficiency, Chronic* / epidemiology
  • Renal Insufficiency, Chronic* / therapy
  • Restless Legs Syndrome* / epidemiology
  • Restless Legs Syndrome* / etiology