Clinical features and subtypes of restless legs syndrome in Chinese population: a study of 359 patients

Background: The clinical spectrum of restless legs syndrome (RLS)has not been described in a Chinese population. We aim to evaluate the detailed clinical profile in a cohort of unselected RLS patients in China. Methods: We enrolled RLS patients continuously according to the diagnostic criteria. Laboratory examinations were performed to exclude mimics and notable comorbidities. Results: A total of 359 patients with RLS were enrolled. RLS symptoms were mostly symmetrical (65.2%), and purely unilateral RLS was not common (5.6%); however, unilateral dominant RLS was relatively more common. Only 1.1% of RLS patients reported no unpleasant sensations in the legs. The largest proportion of RLS patients described their uncomfortable sensation as indescribable (43.5%)and reported soreness (40.4%). In all, 8.9% of RLS patients described their abnormal sensation as painful, and 34.5% of RLS patients reported their symptoms fluctuated with seasonal trends. This population had a higher likelihood of an RLS family history. RLS patients with summer exacerbation had a younger age at RLS onset and longer disease duration (p < 0.01). Iron deficiency without anemia was common in Chinese RLS patients. Early-onset RLS patients were more likely to have a positive family history (p < 0.01), more summer worsening of symptoms (p < 0.01)and more severely disturbed peripheral iron status (p < 0.01)when compared to late-onset RLS patients. Conclusion: The subjective description is somewhat different, with Chinese RLS patients reporting less pain and more soreness than patients from Western countries. Seasonal fluctuation and iron deficiency without anemia are frequently seen in Chinese RLS patients and predict some other features. Differentiating these various subtypes can facilitate optimal management.