Effect of Adenotonsillectomy on Quality of Life in Children With Mild Obstructive Sleep Apnea

Overview

In children, enlarged adenoids and/or tonsils are the most common cause of obstructive sleep apnea (OSA), which is temporary blockage of breathing during sleep. Surgery to remove the tonsils and adenoids is the first-line treatment for disorder, and has been shown to cure the majority of children. However, for children with only a mild degree of OSA and few symptoms, surgery is less clear-cut, since two-thirds of these children do not develop worsening disease. Research shows that some children with mild OSA and behavior problems are helped by removing the tonsils and adenoids. In children with all degrees of OSA, surgery has improved scores on tests that measure quality of life (QOL). The investigators hypothesize that children with mild OSA will demonstrate changes on QOL assessment following adenotonsillectomy. These findings may help to guide the surgeon in selecting the children with mild OSA who are more likely to benefit from surgery.

Obstructive sleep apnea (OSA) is a sleep-related breathing disorder that is characterized by intermittent episodes of upper airway collapse and cessation of airflow during sleep. It comprises the severest extent of a spectrum of sleep disordered breathing (SDB) which includes primary snoring and upper airway resistance syndrome. OSA is a cause cardiovascular morbidity in adults and children and a public health concern, affecting 2-4% of the middle aged population (Giles 2009) and 2-3% of children in the United States (Katz 2010). It is further associated with an increased mortality risk in adults (Giles 2009) and well-described metabolic, cardiovascular, and neuropsychological deficits in children (Katz 2010). The latter symptoms include changes in behavior, memory and cognition, and poor school performance. In children, adenotonsillar hyperplasia is uniformly the most common cause of upper airway obstruction, and the first-line therapy for these children is adenotonsillectomy (Darrow 2007). While its effectiveness is complicated by children with obesity and other comorbidities, the most recent analyses of outcomes using postsurgical apnea-hypopnea index reveal that adenotonsillectomy alone is able to cure approximately 60% of child OSA (Friedman 2010). Improvements have also been shown with neuropsychological outcomes such as behavior, school performance, attention, and others. (Katz 2010). "Mild OSA" is an evolving definition; it is characterized by the polysomnographic finding of AHI range greater than 1 and less than 5, defined by Katz and Marcus.(Wagner 2007) This range corresponds to the difference in the defined pathological minimum AHI for children (normal AHI \< 1) and adults (normal AHI \< 5). In practice, "mild OSA" remains a common reason for delaying adenotonsillectomy in an otherwise asymptomatic child, since children with mild OSA have been shown to exhibit neurocognitive functioning equivalent to controls.(Calhoun 2009) However, psychosocially these children often have problems, and adenotonsillectomy has been shown to improve these children's behavior as measured by atypicality, depression, hyperactivity, and somatization.(Mitchell 2007) Furthermore, among one-third of children with mild OSA, the natural history is progression of disease.(Li 2010) Psychosocial problems also become manifest using health-related quality-of-life (QOL) symptom scores. The study of QOL in children with OSA has become an area of scholarly interest in the last 15 years. It was only in 2000 that an OSA-specific QOL questionnaire was first developed and validated for use in children (2000 Franco). A recent meta-analysis of QOL following adenotonsillectomy revealed significant improvements in QOL scores in patients undergoing surgery for all severity levels of OSA.(2008 Baldassari) This meta-analysis included studies using validated QOL instruments, namely the Child Health Questionnaire (CHQ) and OSA-18. Only one study of QOL in children with mild OSA found no clinically significant differences between patients who underwent adenotonsillectomy and controls; however, disease-specific QOL instrument (such as the OSA-18) was not used.(van Staaij 2004) The investigators hypothesize that children with mild OSA will demonstrate changes on QOL assessment following adenotonsillectomy, particularly in OSA-specific domains. If true, a threshold for preoperative QOL scores may serve as a relative indication for adenotonsillectomy in the setting of mild OSA, independent of behavioral issues.