Restless legs syndrome is associated with cardio/cerebrovascular events and mortality in end-stage renal disease

Eur J Neurol. 2015 Jan;22(1):142-9. doi: 10.1111/ene.12545. Epub 2014 Aug 21.

Abstract

Background and purpose: Earlier studies suggested an association between idiopathic restless legs syndrome (RLS) and cardiovascular diseases. However, the risk of cardiovascular events in patients with secondary RLS due to end-stage renal disease (ESRD) is unclear. Our aim was to examine whether ESRD patients with RLS had an increased risk of cardio/cerebrovascular events and mortality.

Methods: In all, 1093 ESRD patients were recruited between 2009 and 2010. The diagnosis and severity of RLS were assessed in a face-to-face interview. The occurrence of cardio/cerebrovascular events and death were confirmed by medical record review. The association between RLS and the outcomes of interest was examined using an adjusted multivariate Cox regression model.

Results: After a mean follow-up period of 3.7 ± 0.8 years, ESRD patients with RLS had a significantly higher risk of developing cardiovascular events and strokes [adjusted hazard ratio (aHR) 2.82, 95% confidence interval (CI) 2.02-4.11, and aHR 2.41, 95% CI 1.55-3.75, respectively] compared with patients without RLS. Increasing RLS severity was associated with an increasing likelihood of cardiovascular events [mild RLS severity, aHR 1.71 (95% CI 1.02-2.87); moderate, 2.79 (1.64-4.66); severe, 2.85 (1.99-4.46)] and strokes [mild, 1.89 (0.87-4.16); moderate, 2.42 (1.50-3.90); severe, 2.64 (1.49-4.91)] in a dose-dependent manner. RLS also increased the risk of total mortality in patients with ESRD [aHR 1.53 (95% CI 1.07-2.18), P = 0.02]; this association attenuated slightly after stratification by individual RLS severity category [mild RLS severity, aHR 1.44 (95% CI 0.78-2.67); moderate, 1.49 (0.98-2.55); severe, 2.03 (0.93-4.45)].

Conclusions: ESRD patients with RLS demonstrated an increased likelihood of cardio/cerebrovascular events and mortality.

Keywords: cardiovascular disease; cerebrovascular disease; end-stage renal disease; mortality; restless legs syndrome; stroke.

MeSH terms

  • Aged
  • Cardiovascular Diseases / epidemiology*
  • Cardiovascular Diseases / mortality
  • Cerebrovascular Disorders / epidemiology
  • Cerebrovascular Disorders / mortality
  • Comorbidity
  • Female
  • Humans
  • Kidney Failure, Chronic / complications
  • Kidney Failure, Chronic / epidemiology*
  • Male
  • Middle Aged
  • Restless Legs Syndrome / epidemiology*
  • Restless Legs Syndrome / etiology
  • Severity of Illness Index