Epidemiology of restless legs syndrome in French adults: a nationwide survey: the INSTANT Study.

OBJECTIVE: To evaluate the prevalence, characteristics, and treatment of restless legs syndrome (RLS) in France.

METHODS: In this population-based survey, face-to-face home interviews were conducted among a random sample of 10,263 French adults. A French translation of the four features defined by the International RLS Study Group in 1995 was used to assess the prevalence of symptoms consistent with a diagnosis of RLS. Data on severity of symptoms and their management were also collected.

RESULTS: The 12-month prevalence of RLS symptoms in the French adult population was estimated to be 8.5% (95% CI 8.0%, 9.0%), with a higher prevalence (p < 0.001) observed in women (10.8%) than in men (5.8%). Prevalence increases with age until 64 years and decreases thereafter in both sexes. Half of the identified subjects reported symptoms once a week at least. Symptoms were more severe in subjects reporting symptoms once a week at least compared to subjects with less frequent symptoms. In this group, half of the subjects reported a family history, the age at onset was earlier, and severity of symptoms higher. RLS had been previously diagnosed in only 5.3% of the subjects who reported previous medical diagnosis, and recommended RLS drug treatment was received by 3.4% of the 28.7% currently treated subjects.

CONCLUSIONS: Restless legs syndrome (RLS) occurred in 10% of women and 5% of men. RLS prevalence decreases after the age of 64. RLS is often underdiagnosed and few subjects receive recommended RLS drug treatment.