To compare polysomnography (PSG) and self-reported sleep, symptoms (pain and fatigue), and anxiety between children with active and inactive juvenile rheumatoid arthritis (JRA) and examine relations among sleep, symptoms, and anxiety.
Two consecutive nights of PSG, self-reported sleep, and symptoms were obtained in 70 children 6-11 years of age with active (n = 35) or inactive (n = 35) JRA.
On the second (study) night, PSG and self-reported sleep variables were not different, but pain and fatigue were significantly higher (both p <.02) in children with active compared to inactive disease. In a stepwise regression, age, medications, disease status, anxiety, evening pain, total sleep time, and arousals explained 36% of the variance in fatigue and age, disease status, and evening pain were significant (all p <.04) predictors of fatigue. All children showed longer sleep latency and reduced sleep efficiency on the first night in the laboratory.
Sleep was not altered in children with active JRA, however, the "first night effect" suggests that valid laboratory sleep assessments require an adaptation night.