The natural history of sleep disordered breathing in 6-11 year old Caucasian and Hispanic children

Abstract

Sleep disordered-breathing (SDB) including obstructive sleep apnea syndrome (OSAS) is increasingly recognized as an important cause of morbidity in children. Clinical symptoms of OSAS in children include snoring, nocturnal arousals, restlessness during sleep, enuresis, daytime sleepiness and hyperactivity. Evidence also suggests that the adverse effects of SDB include behavioral, learning, and personality problems. No large epidemiological study using polysomnography has been conducted to determine the prevalence and correlates of SDB in young children. The Tucson Children's Assessment of Sleep Apnea study (TuCASA) is a prospective cohort study designed to determine the prevalence of objectively documented SDB in pre-adolescent children and to investigate its relationship to symptoms, performance on neurobehavioral measures, and physiologic and anatomic risk factors. Hispanic and Caucasian children were recruited to participate in TuCASA by soliciting the cooperation of elementary schools in the Tucson Unified School District (TUSD). Through the use of a screening survey completed by parents, the TuCASA study has shown that children between 4-11 years of age with learning problems (LP) are more likely to have habitual snoring (SN) and excessive daytime sleepiness (EDS). Additionally, Hispanic children in this age group are more likely to have parental report of EDS, witnessed apnea (WA), and SN. Similar to studies in adults, girls 4-11 years of age are more likely to have parental report of daytime sleepiness than boys. Furthermore, the TuCASA study has demonstrated the feasibility of collecting high quality unattended multi-channel polysomnography in children ages 5 to 12 years. More importantly, the TuCASA study has documented the relationships between respiratory disturbance indices based on polysomnography and parental report of clinical symptoms of SDB in children ages 6-11. There are threshold values of respiratory disturbance index (RDI) associated with an increase in the prevalence of clinical symptoms of SDB. Until now, data linking objective indices of RDI severity to the presence of clinical symptoms have been lacking. Additionally, these findings contribute much needed information for determining clinically significant levels of RDI based on differing definitions of respiratory events. Therefore, these results represent an important step towards examining the natural history of SDB and the relationship between SDB severity and specific clinical outcomes in pre-adolescent children.