Study objectives: The Tucson Children's Assessment of Sleep Apnea study (TuCASA) is designed to investigate the prevalence and correlates of objectively measured sleep-disordered breathing in pre-adolescent children. This paper documents the methods and feasibility of attaining quality unattended polysomnograms in the first 162 TuCASA children recruited.
Design: A prospective cohort study projected to enroll 500 children between 5 and 12 years of age who will undergo unattended polysomnography, neurocognitive evaluation, and physiological and anatomical measurements thought to be associated with sleep-disordered breathing.
Setting: Children are recruited through the Tucson Unified School District. Polysomnograms and anthropometric measurements are completed in the child's home.
Participants: Of the 157 children enrolled in TuCASA, there were 100 children (64%) between 5-8 years old and 57 children (36%) between the ages of 9 to 12. There were 74 (47%) Hispanic children, and 68 (43%) female participants.
Measurements & results: Technically acceptable studies were obtained in 157 children (97%). The initial pass rate was 91%, which improved to 97% when 9 children who failed on the first night of recording completed a second study which was acceptable. In 152 studies (97%), greater than 5 hours of interpretable respiratory, electroencephalographic, and oximetry signals were obtained. The poorest signal quality was obtained from the chin electromyogram and from the combination thermister/nasal cannula. Parents reported that 54% of children slept as well as, or better than usual, while 40% reported that their child slept somewhat worse than usual. Only 6% were observed to sleep much worse than usual. Night-to-night variability in key polysomnographic parameters (n=10) showed a high degree of reproducibility on 2 different nights of study using identical protocols in the same child. In 5 children, polysomnograms done in the home were comparable to those recorded in a sleep laboratory.
Conclusions: The high quality of data collected in TuCASA demonstrates that multi-channel polysomnography data can be successfully obtained in children aged 5-12 years in an unattended setting under a research protocol.