Sleep disturbance, daytime sleepiness, and neurocognitive performance in children with juvenile idiopathic arthritis.

Juvenile idiopathic arthritis (JIA) (formerly known as juvenile rheumatoid arthritis [JRA]) is one of the most common inflammatory rheumatologic conditions in children and is estimated to affect approximately 300,000 children in the United States.1 JIA is a chronic disease with recurring episodes of acute inflammation. The course of the disease is highly variable. Some children experience infrequent episodes of inflammation and recover quickly from symptoms; others experience frequent disease episodes and significant disability.2 Many children show remarkable resilience in adapting to life with JIA, while others appear to be susceptible to the intensity of the symptoms and show physical, emotional and behavioral manifestations of marked distress. Children with JIA fatigue easily, experience joint inflammation, pain, limited mobility and report poor sleep quality and daytime sleepiness.3–8 Longer mean self-reported nap duration (∼ one h) and shorter mean sleep latencies (10.4 ± 2.6 min)6 in multiple sleep latency tests (MSLTs) have been reported in JIA children compared to mean sleep latencies from previous studies of children (16.5 ± 3.3 min to 26.4 ± 2.8 min).7,8 Daytime sleepiness in JIA could be linked to reduced sleep continuity associated with some aspect of (e.g., inflammation) or response (e.g., pain, anxiety) to the disease. Children with greater disease severity (e.g., greater number of joints affected) had higher scores on the Pediatric Daytime Sleepiness Scale, and daytime sleepiness was significantly correlated with parental reports of pain and degree of interference of JIA in the child's life.3 Numerous factors (age, medications, disease status, anxiety, pain, total sleep time, and arousals) have been associated with fatigue in JIA,5,9 but less in known about daytime sleepiness. Daytime sleepiness could be related to conditions that disrupt sleep continuity and negatively affect daytime performance. Along with daytime sleepiness, parents often report on questionnaires symptoms suggestive of sleep disorders, such as parasomnias (sleep terrors, walking) and sleep disordered breathing (SDB).4,5 More arousals and awakenings/hour and a greater proportion of arousal-associated periodic limb movements have been reported in JIA compared to healthy children.6,7 In a previous report, we found a higher apnea/hypopnea index (AHI > 1)9 than had been reported in previous studies of JIA.6,7 Parental reports of snoring and sleepiness have been associated with poor cognitive performance.10,11 Daytime sleepiness that has been associated with arousals, snoring, and AHI 12–15 is thought to underlie poor school performance, negative mood, changes in behavior, and neurobehavioral performance in school aged children.16–19 In particular, decrements in verbal fluency, visual-spatial ability, sustained attention, mental flexibility, and vigilance have been noted.14,18,20–22 Most of the research on sleepiness and neurobehavioral performance has been studied in children with SDB. Daytime sleepiness has the potential to negatively impact neurobehavioral performance in JIA, but to our knowledge there have been no prior reports. As part of our ongoing research of sleep disturbance in children with JIA, we compared self-report and physiological (MSLT) measures of daytime sleepiness and neurobehavioral performance between children with active and inactive JIA. Based on our prior findings of more pain and fatigue in children with active compared to inactive JIA,9 we hypothesized that daytime sleepiness would be increased and scores on neurobehavioral performance tests would be decreased in children with active compared to inactive JIA. We also explored relations among polysomnographic indices of sleep disturbance (number of wake bouts, snoring, arousals, apnea/ hypopnea index [AHI]), daytime sleepiness, and neurobehavioral performance.