Should obstructive hypopneas be included when analyzing sleep studies in infants with Robin Sequence?

OBJECTIVE: We have used an obstructive apnea index of >/=3 as treatment indication for infants with Robin sequence (RS), while the obstructive apnea-hypopnea index (OAHI) and a threshold of >/=5 is often used internationally. We wanted to know whether these two result in similar indications, and what the interobserver variability is with either asessement. METHODS: Twenty lab-based overnight sleep recordings from infants with isolated RS (median age: 7 days, range 2-38) were scored based on the 2020 American Academy of Sleep Medicine guidelines, including or excluding obstructive hypopneas. RESULTS: Median obstructive apnea index (OAI) was 18 (interquartile range: 7.6-38) including only apneas, and 35 (18-54) if obstructive hypopneas were also considered as respiratory events (OAHI). Obstructive sleep apnea (OSA) severity was re-classified from moderate to severe for two infants when obstructive hypopneas were also considered, but this did not lead to a change in clinical treatment decisions for either infant. Median interobserver agreement was 0.86 (95% CI 0.70-0.94) for the OAI, and 0.60 (0.05-0.84) for the OAHI. CONCLUSION: Inclusion of obstructive hypopneas when assessing OSA severity in RS infants doubled the obstructive event rate, but impaired interobserver agreement and would not have changed clinical management.