MedicalResearch.com Interview with:
Karen Thorpe PhD
Professor, Developmental Psychology
Program Leader, Early Education and Development Group
Program leader, Sleep in Early Childhood Group
School of Psychology and Counseling
Queensland University of Technology Australia
MedicalResearch: What is the background for this study?
Professor Thorpe: Sleep is undoubtedly important not only for how well we think, feel and behave in our daily lives but also for longer-term health. In childhood, the quantity and quality of night-time and 24 hour sleep have consistently been identified as predictor of health. For example, night sleep predicts weight status. These findings have led to the hypothesis that increasing quantity of sleep through promoting daytime sleep would benefit child health. We sought to look for evidence on the independent effects of daytime sleep on child health, learning and behavior to assess whether this hypothesis was supported.
MedicalResearch: What are the main findings?
Professor Thorpe: We conducted a systematic review of the literature for children aged 0-5 years. We focus on early childhood as a period of significant sleep transition in which sleep consolidates into the nighttime and naps cease. We found 26 papers that provided data on the independent effects of daytime sleep. Outcomes included quantity and quality of night sleep, accidents, weight status, memory and learning, and behavior. The most consistent evidence related to night sleep. The evidence suggests that beyond the age of 2 years when cessation of napping becomes more common, daytime sleep is associated with shorter and more disrupted night sleep. Those studies examining direction of effect all report that daytime sleep is not a response to poor night sleep but rather precedes poor night sleep. Evidence relating to cognitive functioning, accidents, weight status and behavior were less conclusive. More research and higher quality research that can provide evidence on causality was advocated.
MedicalResearch: What should clinicians and patients take away from your report?
Professor Thorpe: The age of cessation of napping varies considerably. The age of 2 years should not be seen as definitive point from which napping should be discouraged. Rather, clinicians and parents of young children should respond to their child’s sleep need. Provision of opportunity to nap for those who have not yet consolidated their sleep into the nighttime is likely important. However, there is not evidence of benefit through prolonging and promoting napping beyond the period when children cease to need a regular nap. For children presenting to clinicians with night sleep difficulties napping behaviours should be considered as a potential factor.
MedicalResearch: What recommendations do you have for future research as a result of this study?
Professor Thorpe: Sleep studies to date focus on 24 hour or night sleep. There is little high quality evidence regarding the independent effects of daytime sleep on child health. Considerably more studies are required. This is particularly important to guide parents and non-parental carers of young children in determining sleep practices. Studies providing physiological measurement of sleep and long-term follow-up of child outcomes are particularly important. Children attending daycare are particularly of interest because naptime is typically a standard practice regardless of individual variation in point of transition to monophasic sleep.
Arch Dis Child archdischild-2014-307241Published Online First: 17 February 2015 doi:10.1136/archdischild-2014-307241
MedicalResearch.com Interview with:Karen Thorpe PhD (2015). After Age 2, Daytime Naps May Interfere With Nightime Sleep