Association of Apnea vs Hypopnea Predominance With Pediatric Sleep Apnea Outcomes: A Secondary Analysis of the Childhood Adenotonsillectomy Trial.

Importance: Children with apnea-predominant obstructive sleep apnea (OSA) are hypothesized to have a more severe form of the disease. However, research is lacking as to whether there is a significant difference in outcomes between children with apnea-predominant vs hypopnea-predominant OSA.

Objective: To assess the association between baseline apnea-predominant or hypopnea-predominant OSA on polysomnography and quality of life (QOL) outcomes in children with obstructive sleep apnea managed by watchful waiting with supportive care (WWSC) or adenotonsillectomy (AT).

Design, Setting, And Participants: This case-control study is a secondary analysis of a randomized clinical trial, the Childhood Adenotonsillectomy Trial, which was conducted at multiple tertiary children's hospitals from October 2007 to June 2012. Children aged 5.0 to 9.9 years with OSA were randomized to WWSC or AT and underwent polysomnography and completed validated QOL and symptom assessments at baseline and 7 months. The current data analysis was performed from October 2020 to February 2022.

Main Outcomes And Measures: Apnea-predominant OSA was defined as an apnea hypopnea index (AHI) greater than 2 with more than 50% of the obstructive events being apneas. Patients were considered to have hypopnea-predominant OSA if they had an AHI greater than 2 and more than 50% of the obstructive events were hypopneas.

Results: A total of 386 children (185 boys [48%]; mean [SD] age, 6.56 [1.4] years) were analyzed. The mean (SD) obstructive AHI for patients was 6.98 (5.62), with 198 patients (51%) having mild disease. Thirty-seven children (10%) had apnea-predominant OSA at baseline. Black children were at increased risk for apnea-predominant OSA vs White children (odds ratio [OR], 13.40; 95% CI, 5.70-33.90). Children with apnea predominance were more likely to have severe OSA (AHI >10) compared with children with hypopnea predominance (OR, 2.30; 95% CI, 1.03-5.03); baseline Pediatric Sleep Questionnaire and OSA-18 QOL scores were similar between the 2 groups. Among children undergoing AT, those with baseline apnea predominance were more likely to have a Pediatric Sleep Questionnaire score greater than 0.33 at follow-up (OR, 3.30; 95% CI, 1.01-10.80). Rates of OSA resolution and improvements in QOL scores following AT or WWSC were similar between the apnea-predominant and hypopnea-predominant groups.

Conclusions And Relevance: In children with OSA, apnea-predominant disease is uncommon. Apnea predominance was not associated with symptom resolution and cure rates in children undergoing AT or WWSC for OSA. Further research is needed to assess how apnea predominance affects AT outcomes in children with more severe disease.