Restless legs syndrome and sleep bruxism: prevalence and association among Canadians

A survey conducted through personal interviews was done in Canada to estimate the prevalence of subjective symptoms related to restless legs syndrome (RLS) and to sleep bruxism. Of the 2,019 respondents, all over 18 years of age, 15% reported leg restlessness at bedtime; 10% reported unpleasant leg muscle sensations associated with awakening during sleep and with the irresistible need to move or walk. Both these complaints are related to RLS. The prevalence of RLS-related symptoms increased linearly with age. Tooth grinding, a symptom related to sleep bruxism, was reported by 8% of the subjects; in contrast to RLS-related symptoms, the prevalence of tooth grinding decreased linearly with age. RLS-related symptoms were reported more frequently in Eastern provinces than in Ontario and Western Canada, and more frequently in Roman Catholic and French-speaking responders. This was not the case for sleep bruxism; between 14.5% and 17.3% of the subjects who reported subjective RLS-related symptoms also reported tooth grinding. Conversely, 9.6-10.9% of the tooth grinders reported RLS-related symptoms. These data suggest that both sleep movement disorders can be concomitant and that socio-geographic and age characteristics influence the prevalence of reports.