Adverse associations of sleep problems in Australian preschoolers: national population study.

OBJECTIVE: In contrast to school-aged children, the impact of sleep problems in preschool-aged children is not well documented. We aimed to determine relationships between preschool-aged child sleep problems and child behavior; health-related quality of life; verbal, preliteracy, and early numeracy skills; diagnosis of attention-deficit/hyperactivity disorder; and injury.

PARTICIPANTS AND METHODS: Participants included families (n = 4983) participating in the first wave of the Longitudinal Study of Australian Children, a nationally representative study of Australian children aged 4 to 5 years surveyed from March to November 2004. Measures consisted of a primary caregiver's report of whether their child had a sleep problem (none versus mild versus moderate/severe); specific sleep patterns occurring > or = 4 nights per week; health-related quality of life (by using the Pediatric Quality of Life Inventory 4.0); behavior (by using the Strengths and Difficulties Questionnaire) and parent-reported diagnosis of attention-deficit/hyperactivity disorder; and injury requiring medical attention in the past 12 months. Tests of receptive vocabulary and preliteracy/numeracy skills (by using the Who Am I? developmental assessment and the adapted Peabody Picture Vocabulary Test, 3rd Edition) were directly administered to each child.

RESULTS: Sleep problems were common, and compared with children without sleep problems, children with sleep problems had poorer child health-related quality of life, more behavior problems, and higher rates of attention-deficit/hyperactivity disorder. Difficulty going to sleep and morning tiredness had greater adverse associations than snoring or night waking.

CONCLUSIONS: Given that sleep problems are very common, the adverse outcomes shown here could affect the transition to school for a very large number of preschoolers.