Cognition After Early Tonsillectomy for Mild OSA

Abstract

OBJECTIVES: It remains uncertain whether treatment with adenotonsillectomy for obstructive sleep apnea in children improves cognitive function. The Preschool Obstructive Sleep Apnea Tonsillectomy and Adenoidectomy study was a prospective randomized controlled study in which researchers evaluated outcomes 12 months after adenotonsillectomy compared with no surgery in preschool children symptomatic for obstructive sleep apnea.METHODS: A total of 190 children (age 3-5 years) were randomly assigned to early adenotonsillectomy (within 2 months) or to routine wait lists (12-month wait, no adenotonsillectomy [NoAT]). Baseline and 12-month assessments included cognitive and behavioral testing, medical assessment, polysomnography, and audiology. The primary outcome was global IQ at 12-month follow-up, measured by the Woodcock Johnson III Brief Intellectual Ability (BIA). Questionnaires included the Pediatric Sleep Questionnaire, Parent Rating Scale of the Behavioral Assessment System for Children-II, and Behavior Rating Inventory of Executive Function, Preschool Version.RESULTS: A total of 141 children (75.8%) attended baseline and 12-month assessments, and BIA was obtained at baseline and 12-month follow-up for 61 and 60 participants in the adenotonsillectomy versus NoAT groups, respectively. No cognitive gain was found after adenotonsillectomy compared with NoAT, adjusted for baseline; BIA scores at 12-month follow-up were as follows: adenotonsillectomy, 465.46 (17.9) versus NoAT, 463.12 (16.6) (mean [SD]). Improvements were seen for polysomnogram arousals and apnea indices and for parent reports of symptoms (Pediatric Sleep Questionnaire), behavior (Behavior Assessment System for Children behavioral symptoms, P = .04), overall health, and daytime napping. CONCLUSIONS: Structured testing showed no treatment-attributable improvement in cognitive functioning of preschool children 12 months after adenotonsillectomy compared with NoAT. Improvements were seen after adenotonsillectomy in sleep and behavior by using polysomnogram monitoring and parental questionnaires.WHAT'S KNOWN ON THIS SUBJECT: Studies to evaluate changes in neurocognition after adenotonsillectomy for obstructive sleep apnea suggest that younger children may have potential for greater improvement. The previous study with a randomized design was in school-aged children.WHAT THIS STUDY ADDS: This randomized study of preschool children showed reduced frequency of day naps and confirmed polysomnographic and behavioral improvements after adenotonsillectomy compared with those still awaiting surgery, but our primary analysis showed no improvement in global IQ.

Effect of surgical intervention for mild childhood obstructive sleep apnoea on attention and behavioural outcomes: A randomized controlled study

“…13 Global IQ as assessed by the Woodcock Johnson III Brief Intellectual Ability did not show significant gain at 12-month follow-up in children aged 3-5 years who underwent AT versus those without intervention. 13 A possible explanation for the negative finding was that the participants did not exhibit neurocognitive deficits at baseline when compared to age-appropriate norms, which was also demonstrated in a previous crosssectional study comparing preschoolers with and without OSA. 33 A similar floor effect may also explain the negative findings obtained from our current study.…”

“…14 However, nearly all published studies included children across all categories of severity and only two studies focused on mild disease. 13,15 One of them is a retrospective review which found that AT leads to a significant improvement in apnoea-hypopnoea index (AHI) on follow-up. 15 The other one is a recently published randomized controlled study which demonstrated an improvement in AHI accompanied by an improvement in behaviour but not cognitive function after AT in preschoolers.…”

Polysomnography in children with obstructive sleep apnoea and neurocognitive disorders

“…Since OSA has been known to cause memory, learning and scholastic issues 7 often of different severity, diagnostic code classification is difficult. Furthermore, the 2 major end points used by the CHAT and POSTA trials were behavioural/functional and executive functioning 8,9 1).…”

“…Furthermore, the 2 major end points used by the CHAT and POSTA trials were behavioural/functional and executive functioning. 8,9 Therefore, we utilised those codes which were most associated with OSA after exclusion criteria were applied (Table 1).…”

Surgical treatment of obstructive sleep apnoea in childhood: Lessons for the way forward

“…However, there appears to be greater improvements after surgery in less subjective measures as well: teacher-reported behaviour in the Childhood Adenotonsillectomy Trial (CHAT) 6 and persistence of daytime napping (a potential measure of daytime sleepiness in very young children) in the Preschool Obstructive Sleep Apnoea Tonsillectomy and Adenoidectomy (POSTA) study. 10 The unknown duration of, and likely inter-individual variability in, recovery of cognitive and behavioural functioning after the treatment of OSA also confounds our understanding of optimal treatment in this condition. The duration of follow-up in the randomized trials has been 6-12 months, 6,7,9,10 whereas there is reason to think that improvements in cognitive function may take longer than that.…”