Incidence of sleep disorders in children with presumed normal variant short stature

Objective: To determine whether unrecognized obstructive sleep apnoea (OSA) is present in some children diagnosed with normal variant short stature. Methods: One hundred and fifty-eight children aged less than 15 years and previously diagnosed with familial short stature or constitutional delay of growth were identified from the endocrine clinic database. A validated, standardized questionnaire designed to screen for symptoms of sleep disorders in children was mailed to the parents of eligible children. Results: Fifty-three questionnaires were returned. Fifteen of these had an abnormal score (greater than the mean + three standard deviations in 1157 normal control children). Of these, 10 agreed to a sleep study. Overnight polysomnography showed no evidence of OSA or other sleep/breathing disorders. However, five (half) children showed frequent periodic leg movements of 6.3, 9.2, 9.4, 10.2 and 15.4 per h (adult normal < 5 per h). Conclusions: We did not find OSA among a group of children with normal variant short stature. However, we found frequent periodic limb movements during sleep in a large proportion of the subjects, the significance of which remains to be determined.