Sleep is an essential component to daily functioning and is necessary for multiple aspects of development, as well as energy conservation  and brain waste clearance . Sleep also helps modulate cognition, disease, immune response, and psychological state [1–3]. Although adequate sleep is known to be imperative for optimal functioning, average sleep duration (i.e., length of sleep) from infancy through adolescence has steadily declined within the general population over the last 20 years [4, 5]. The consequences of insufficient sleep or reduced sleep duration in children have been associated with a wide range of adverse physical and mental health outcomes , as well as deficits in cognition [6–10], and executive functioning (EF; higher order thinking skills) in particular . Increased risk and incidence of psychiatric disorders are also observed [11, 12], as sleep and mental health appear to be bidirectional processes . Accordingly, sleep difficulties in children are associated with poorer quality of life and secondary familial effects (e.g., maternal stress) . Sex and race/ethnicity are important factors to examine as well, considering prior studies reveal that girls consistently demonstrate greater sleep duration and shorter sleep latency (i.e., amount of time to fall asleep) than boys , while ethnic/racial minority  is identified as a risk factor for disrupted sleep.
While daytime napping is important for early cognition, transition to monophasic sleep by age five is a developmental marker of brain maturation . As children age, lower sleep quality, longer sleep latency, more arousals, and increased time spent in lighter sleep may be associated with napping behaviors due to circadian misalignment, as the light-dark cycle and endogenous circadian rhythms are at risk of deviation . Additionally, according to the two-process model of sleep regulation, napping behaviors can interfere with circadian regulatory processes by delaying accumulation of sleep pressure necessary for successful sleep initiation .
Chronic and acute medical conditions increase the risk of sleep disruption in children . Pediatric cancer and associated treatments significantly interfere with multiple aspects of sleep, such as sleep latency , sleep duration , daytime sleepiness , sleep habits (e.g., disturbed sleep-wake rhythm) , and fatigue . Pediatric patients both with and without central nervous system involvement of their cancer experience greater disturbances related to sleep initiation and maintenance compared to typically developing peers . However, patients with pediatric brain tumor (PBT) in particular are at increased risk for sleep-related deficits, as the location of the tumor (e.g., with disruption to the hypothalamic-pituitary region) and associated focal treatments (e.g., resection, cranial irradiation) may disrupt circadian rhythms [27–29]. Moreover, increased daytime sleepiness and longer sleep duration in survivors of PBT can persist years after treatment into adulthood .
Neurocognitive impairment (including executive dysfunction) has been found to be correlated with fatigue and sleep problems in long-term female survivors of childhood leukemia, though not with their male counterparts . Additionally, recent investigation of survivors of PBT with neurocognitive complaints in Amsterdam revealed 48% presented with sleep problems, which was associated with parent-reported executive dysfunction as measured by the Behavior Rating Inventory of Executive Function (BRIEF) . While the need for adequate sleep to function properly is well documented, the association between inadequate sleep and adaptive functioning deficits among patients with PBT has yet to be explored, despite poor adaptive functioning being a known late effect of pediatric cancer .
Given the nature of how sleep needs and patterns shift drastically throughout the developmental period, the primary goal of this retrospective exploratory study was to further investigate sleep factors (i.e., subjective sleep concerns, nocturnal sleep duration, daytime napping patterns) across different age ranges of patients with PBT, as well as examine the impact of these sleep factors on reported functioning.