Parents recognize the importance of sleep for newborns, infants, and toddlers. When well rested, infants are less cranky, preschoolers are happier, and kindergartners are less disruptive. Somewhere between early grade school and high school, life happens, and days become packed full of activities making sleep take a back seat. Bedtime shifts from 7:00 p.m. in elementary school to 11:00 p.m. or later for high schoolers. Scientists and educators alike recognize that adolescents and young adults need more, not less, sleep as they struggle with waking up early for that 7:15 a.m. school start time. Factor in after-school sports and part-time jobs, and the average adolescent clocks in less than five hours of sleep per day.
In his commentary “Sleep and the Developing Brain,” Dr. Ronald Dahl cited that sleep was one of the three most fundamental requirements for healthy growth and development in young children, in addition to loving support and protection, and adequate nutrition.1 Research suggests that when the growing brain is sleep deprived, children and adolescents present with symptoms of irritability, attention deficit hyperactivity disorder, and various other behavioral problems.2 The primal need for adequate sleep is even more important for individuals living with sickle cell disease (SCD).
SCD is an inherited blood disorder frequently associated with pain. Like all adolescents with packed schedules and oh so little time, youth with SCD will also experience lack of sleep. They also experience sleep deprivation due to the pain associated with their disease, from frequent nighttime waking resulting from enuresis (a common complication of SCD related to hyposthenuria), and possibly concurrent sleep-disordered breathing complications. Having a diagnosis of SCD was found in regression analysis to be associated with worse sleep quality (going to bed, falling asleep, maintaining sleep, and re-initiating sleep after waking) over and above the influence of race, sex, gender, and pubertal status among adolescents.3
Researchers in North Carolina recently published their work on a model that explores the sleep-age-pain connection among youth. This model postulates that sleep quality and quantity affects the pain experience and is modulated by age and other factors such as mood and social determinants. No surprise there. So, why don’t we pay more attention? Dr. Cecelia R. Valrie and colleagues recently published the results of a prospective study using mobile health technology to assess the quantitative and qualitative aspects of pain and sleep, revealing the sleep-pain relationship in youth with SCD. Unique to this study was the deployment of subjective and objective strategies to assess sleep quality and quantity, and pain-leveraging technology. This relatively large study enrolled 88 youth with SCD between the ages of 8 to 17 years. Subjects were asked to complete four weeks of subjective or qualitative ecological momentary assessments (EMAs) — a fancy term for a mobile app–based diary — that they logged every morning to assess the prior night’s sleep, and every evening to assess pain and mood during the day. This was coupled with objective, quantitative assessments using sleep actigraphy for the first two weeks of the study, and pulse oximetry via a wrist-worn device for the first two days of the study.
Surprisingly, the completion rates for both the qualitative and quantitative assessments were robust. The EMA entry completion rate was high at 81.87 percent, representing data completion for 3.64 of four possible weeks. Adherence to sleep actigraphy was also good, with an average of 12.73 nights of usable sleep actigraphy data among the 84 percent of youth who had more than five days of data collected. Adherence to pulse oximetry among the 81 percent who had more than two hours of data collected, averaged 8.55 hours.
Authors noted a high prevalence of sleep apnea (74.6% of participants, using a cutoff of an Apnea Hypopnea Index of 24), and the subjective sleep quality and pain severity evidenced a bidirectional relationship. Reporting poor sleep at night predicted higher pain during the following day, and higher pain during the day predicted poor subjective sleep quality the night. Furthermore, older age was linked with fewer hours slept and difficulty falling asleep. These results demonstrated that the power of sleep to predict pain increased with age; the accumulation of poor sleep leads to cumulative damage to the body and brain that only gets worse over time. This means that the effect of sleep on pain pattern is worse during a time at which adolescents typically experience less sleep. The snowball effect of poor sleep on cognition, inflammation, and immunity sets the stage for increased pain and disease activation in SCD at a time when the complex interaction of pubertal biology with environment and societal factors puts them at high risk for psychosocial problems. Establishing healthy sleep patterns early on helps reduce the effects of poor sleep on pain for individuals living with SCD.
So how can we help all youth, particularly those living with SCD, to get more sleep and sleep better? The authors propose early interventions to address sleep hygiene with all persons with SCD that focus on both behavioral and clinical strategies. Setting a firm and consistent bedtime, eliminating electronic devices and screens that emit blue light, and reducing fluid intake close to bedtime (to lessen frequent wakening to use the bathroom) are age-old strategies used for infants, toddlers, and preschoolers that work for all ages. A comprehensive clinical evaluation to identify symptoms and signs of sleep-disordered breathing, movement disorders, and enuresis offers opportunity for intervention once identified. In short, a cup of warm milk with dinner followed by a bedtime story and a soft lullaby would go a long way to improving sleep and pain outcomes for persons living with SCD, regardless of age.
Dr. Osunkwo indicated no relevant conflicts of interest.