Periodic Limb Movement Disorder (PLMD) prevalence is not known. The prevalence of PLMD in children and adolescence is elevated in children with attention-deficit hyperactivity disorder (ADHD)2 and some psychiatric disorders. (For information on the difference between PLMD and periodic limb movements during sleep, see Periodic Limb Movement Disorder (PLMD).
2 Picchietti DL, Walters AS. Moderate to severe periodic limb movement disorder in childhood and adolescence. Sleep. 1999;22:297-300.