Prognostic Impact of Restless Legs Syndrome on Patients with Heart Failure

The restless legs syndrome (RLS) is a neurological disorder characterized by an irresistible urge to move the legs or arms for relief of uncomfortable or unpleasant sensations. Prevalence and prognostic impact of RLS on patients with heart failure (HF) remain unclear. We aimed to investigate the clinical characteristics and prognostic impact of RLS on HF patients.Consecutive 338 HF patients were evaluated for RLS and divided into two groups on the basis of presence of RLS: HF patients with RLS (RLS group, n = 29) and HF patients without RLS (non-RLS group, n = 309). We compared clinical characteristics, parameters of laboratory data and echocardiography, and rate of follow-up cardiac events including worsening HF and cardiac death between the two groups. Compared with the non-RLS group, the RLS group had higher prevalence of anemia (65.5% versus 40.8%, P = 0.010), higher usage of inotropic agents (31.0% versus 15.2%, P = 0.028), higher levels of B-type natriuretic peptide (570.8 versus 215.8 pg/mL, P = 0.018), and lower levels of left ventricular ejection fraction (40.4% versus 48.4%, P = 0.019). By contrast, age, gender, prevalence of other co-morbidities and medications were comparable between the groups. In the Kaplan-Meier analysis, the cardiac event rate was significantly higher in the RLS group than in the non-RLS group (log-rank P = 0.034). In the Cox proportional hazard analysis, RLS was a predictor for cardiac events in HF patients (hazard ratio: 1.783, 95% confidence interval: 1.038-3.063).RLS is associated with adverse prognosis in HF patients.