Restless Legs Symptoms and Periodic Leg Movements in Sleep Among Patients with Parkinson’s Disease

Background: The association between restless legs syndrome (RLS) and Parkinson’s disease (PD) remains controversial, with epidemiologic and descriptive evidence suggesting some potential overlap while mechanistic/genetic studies suggesting relative independence of the conditions. Objective: To examine a known, objectively measured endophenotype for RLS, periodic leg movements (PLMS) in sleep, in patients with PD and relate that objective finding to restless legs symptoms. Methods: We performed polysomnography for one (n = 8) or two (n = 67) consecutive nights in 75 PD patients and examined the association of PLMS with restless legs symptoms. Results: We found no association between restless legs symptoms and PLMS in PD. Prevalence of both was similar to data reported previously in other PD samples. Conclusion: We interpret these results as suggesting that restless legs symptoms in PD patients may represent a different phenomenon and pathophysiology than RLS in the non-PD population.