Study identifies risk factors for restless legs syndrome, effects on patients on hemodialysis
Researchers have identified several risk factors for restless legs syndrome in patients on hemodialysis, a condition found to be highly prevalent in this patient population. In addition, the effects of restless leg syndrome on these patients were determined.
“Restless legs syndrome/Willis-Ekbom disease (RLS/WED) is a common sleep-related movement disorder,” Li-Yan Zhang, of the department of neurology at Beijing Friendship Hospital in China, and colleagues wrote. “ ... RLS affects 3.5[% to] 10% of adults in the general population. A signicantly higher prevalence of RLS ranging from 12% to 62% has been reported in patients with end-stage renal disease.”
Arguing that the pathophysiology of RLS in patients on hemodialysis remains undetermined — with various studies presenting conflicting results — the researchers sought to explore risk factors and related outcomes. They recruited 354 patients on hemodialysis (mean hemodialysis duration 86 months; 26.5% with kidney transplantation failure) and diagnosed RLS with the International RLS Study Group criteria. Patients were further evaluated using the Epworth Sleepiness Scale (for “excessive daytime sleepiness”), the Hamilton Anxiety Scale, the Hamilton Depression Scale and the Pittsburgh Sleep Quality Index. Both cardiovascular (including myocardial infarction, angina pectoris, heart failure, arrythmia and hypertension) and cerebrovascular (including cerebral infarction, cerebral hemorrhage and transient ischemia attack) events were recorded during 9 months of follow-up.
Researchers found, for all patients included in the study, the prevalence of RLS was 40.7% (144 total patients; 19.4% with severe RLS). The onset of RLS symptoms occurred after the initiation of hemodialysis in 82.6% of these patients, with patients who had kidney transplantation failure rating their RLS as more severe than those without transplantation. Risk factors included duration of hemodialysis, hypersensitive C-reactive protein, hyperparathyroidism, glycosylated serum protein and treatment with erythropoietin.
Compared with participants without RLS, those with the condition had significantly higher Epworth Sleepiness Scale scores and Pittsburgh Sleep Quality Index scores (notably sleep quality, sleep latency and daytime dysfunction), as well as higher Hamilton Depression Scale scores. No significant between-group difference was observed for the Hamilton Anxiety Scale score.
Regarding adverse outcomes, researchers determined the incidence rate of cardiovascular diseases to be 18.8% in the RLS group vs. 8.6% in the non-RLS group. No significant between-group difference was observed in newly diagnosed cerebrovascular diseases or mortality.
“Despite the high prevalence of RLS in the hemodialysis patients in the current study, the awareness rate of RLS was 27.7%, which was quite low,” the researchers wrote. “The low awareness rate of RLS may impede the early diagnosis of this disease.” – by Melissa J. Webb
Disclosures: The authors report no relevant financial disclosures.