Background: Extraintestinal manifestations of Crohn's disease (CD) have not previously included the central nervous system (CNS). Restless legs syndrome (RLS) is a CNS disorder that is either idiopathic or secondary to a number of diseases. The aim of this study was to determine if RLS was associated with CD because both are associated with iron deficiency, inflammation, and bacterial overgrowth.
Methods: Consecutive CD outpatients (N = 272) were prospectively surveyed at 4 centers for criteria for RLS. Incidence (having RLS at any point in time), prevalence (having RLS at time of survey), clinical characteristics, risk factors, and potential qualitative relationship between RLS and gastrointestinal symptoms were queried.
Results: The incidence of RLS in patients with CD was 42.7%. Prevalence was 30.2% compared with 9% of spouses. CD patients with and without RLS had a mean age of 46.8 versus 42.6 years, small intestine involvement in 77.9% versus 66.7%, colon involvement in 39.7% versus 63.2%, and prior iron deficiency anemia in 49.3% versus 33.1%. There was no difference between the CD groups with respect to current iron deficiency, RLS family history, or rare prevalence of concomitant RLS disorders. In 91.8% of patients with RLS and CD, RLS started during or after the onset of CD diagnosis. Among 73 patients with RLS, 67 (44.5%) stated there was a relationship between qualitative RLS symptom improvement with overall CD symptom improvement.
Conclusions: These results demonstrate that RLS occurs frequently in CD and appears to be a possible extraintestinal manifestation. The potential relationship of RLS with CD activity warrants further investigation.