Clinical characteristics and differences in health status according to changes in RLS severity (IRLSc) over 36 months.

*p for differences between the 3 groups derived from one-way analysis of variance (ANOVA) unless otherwise noted.aChi-square test for the difference between gender.bChange in the International Restless Legs Study Group (IRLSSG) Rating Scale for severity of RLS between baseline and 36 months follow-up: worsening = increase in score by >5 points, unchanged = change in score not more than ±5 points, improving = decrease in score >5 points.cInternational Restless Legs Study Group Rating Scale for severity of RLS (IRLS).