Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

BACKGROUND Objective of the study is to assess prevalence and survival among end stage renal disease patients with restless legs syndrome (RLS) within a national database (USRDS). METHODS A case-control, retrospective analysis was performed. Differences in characteristics between the groups, RLS and those with no sleep disorder (NSD), were determined using χ2 tests. Cox proportional hazard regression was used to assess survival between those with RLS and propensity score matched controls. RESULTS Cases of restless legs syndrome were defined as patients that had received an ICD-9 code of 333.94 at any point during their treatment (n = 372). RLS group demonstrated a significantly higher proportion of patients with major depressive disorder, dysthymic disorder, anxiety, depression, minor depressive disorder, and psychological disorder. The difference between the survival was not statistically significant in those without sleep disorder as compared to those with RLS (HR =1.16±0.14, p = 0.3). CONCLUSIONS True prevalence of RLS in dialysis patients can only be estimated if knowledge gap for care providers in diagnosis of RLS is addressed. RLS patients also have increased incidence of certain psychological disorders which needs to be addressed.