A factor analysis of sleep problems and their psychological associations in children with Down's syndrome

The aims of the study were (a) to identify statistically derived sleep disturbance factors in children with Down's syndrome and (b) to explore the possibility that these factors have different psychological associations when compared to each other. Principal components analysis was performed on the results of a parental sleep questionnaire survey on 91 children with Down's syndrome. Three significant sleep disturbance factors were obtained: (a) those where the problem was primarily one of getting the child to go to bed and/or settling to sleep (sleep onset problems); (b) those where the problem was characterised by disturbances during the night, i.e. nocturnal wakings and restlessness (sleep maintenance problems); and (c) those where the problem was primarily one of disordered breathing during sleep. Children showing any one of these types of sleep problems had significantly higher daytime behaviour problem and maternal stress scores than children showing none. Children showing disturbances through the night had higher daytime behaviour scores than all the other groups on virtually all the daytime scales. The findings of the study are discussed along with further research possibilities.