Gender differences in the presentation of subjects with restless legs syndrome

To better understand the origin of the disproportionate number of women in previous treatment studies of patients with restless legs syndrome (RLS).

We conducted a survey in a self-selected group of patients who responded to print and radio recruiting advertisements regarding a clinical trial for RLS. Subjects completed a questionnaire which solicited information on presenting features of RLS, sleep-related symptoms, co-morbidities and family history.

A total of 158 (63% female) subjects with a mean age of 49 (+/-16) years fulfilled the criteria for putative diagnosis of RLS and participated in the study. There was no gender bias as far as duration of RLS, incidence of family history, number of affected days per week, or severity of daytime sleepiness was concerned. There was a subtle gender bias in sleep-related symptoms (involuntary movements when awake, sleep onset difficulties and frequent wakings at night) where a disproportionately high number of women subjects presented with all three symptoms. For any one symptom, or any pair of symptoms, there were no gender differences. Women also were more likely to present with co-existent hypothyroidism. Both male and female subjects were more likely to recall female relatives affected with RLS.

Gender differences associated with symptom load, co-morbidities of RLS and possible patterns of inheritance may contribute to increased numbers of women presenting for treatment of RLS.