Goal: The goal of this study was to characterize the sleep problems of children with cancer who were referred for a comprehensive sleep evaluation.
Materials and methods: A retrospective case series review was conducted of all children with cancer referred to the pediatric sleep clinic from 1994 to 2009 for evaluation of a sleep problem. Seventy children were seen and evaluated during this interval; all had a complete sleep history taken, and further objective sleep evaluations were performed as part of their evaluation only when clinically indicated. An overnight polysomnogram was performed in 53 children. In 36 children with a history of excessive daytime sleepiness (EDS), a multiple sleep latency study was performed the following day. Seven children had a 3-4-week actigraphic study.
Results: Children with neoplasms of central nervous system (CNS) involving the hypothalamus, thalamus, and brainstem were the most commonly referred children and had the most frequent and severe sleep problems. Excessive daytime sleepiness was the most common sleep problem, seen in 60% of children with cancer and in 80% of children with CNS neoplasms involving the hypothalamus, thalamus, and brainstem. Sleep disordered breathing (SDB) was present in 40% of the entire group of children with cancer and 46% of children with neoplasms involving the hypothalamus, thalamus, and brainstem. Children with CNS neoplasms often had more than one sleep problem, most commonly EDS and SDB. In these children, correction of the SDB often did not eliminate the EDS. In children with leukemia, insomnia was the most common sleep problem identified, present in 39%. The causes of the sleep problems were varied and included neurologic injury caused by the neoplasm and/or the CNS-directed treatments; seizures, adenotonsillar hypertrophy, medication side effects, obesity, pain, anxiety, and drug abuse. Some of the sleep problems were present before the diagnosis of cancer, though most developed after treatment was begun. A wide range of intervention strategies were utilized to address the sleep problems and included sleep hygiene/sleep restriction, behavioral counseling, continuous positive airway pressure, bilevel positive airway pressure, tracheotomy with and without a ventilator, diaphragmatic pacers, sedative hypnotics, stimulants, anticonvulsants, and antidepressants. When the sleep problems and their causes were correctly identified and treatments were directed to the specific cause of the problem, the treatments were generally successful.
Conclusions: The sleep problems of children with cancer span the full spectrum of clinical sleep disorders (hypersomnia, sleep disordered breathing, insomnia, parasomnias, and circadian rhythm disorders) and are often present in combinations. Children with neoplasms involving the brainstem, thalamus, and hypothalamus were the most frequently referred for a sleep evaluation, and their sleep problems were most commonly EDS or SDB. Expertise in pediatric sleep disorders can be a valuable resource in the ongoing care of children with cancer.