Associations between age and sleep apnea risk among newborn infants

Objective: Among older children, sleep-disordered breathing (SDB) is associated with measurable neurocognitive consequences. However, diagnostic SDB thresholds are lacking for infants < 12 months. We sought to evaluate the relationship between SDB indices, gestational age (GA), and postmenstrual age (PMA) for infants who underwent clinically-indicated polysomnograms at a tertiary care center. Methods: Every infant < 3-months chronological age whose first clinically-indicated polysomnogram was between 2/2012 and 2/2017 was included. Linear regression was used to evaluate associations between apnea-hypopnea index (AHI), obstructive-apnea index (OAI), and GA and PMA for infants with and without obvious clinical risk factors for SDB (eg, micrognathia and cleft palate). Results: For 53 infants without obvious SDB risk factors (GA 35.6 ± 4.5 weeks; PMA 41.2 ± 4.0 weeks), mean AHI was 27 ± 18 and OAI 2.9 ± 4.5. There was a weak inverse relationship between AHI and PMA (r ² = 0.12, P = 0.01), but AHI was not predicted by GA (r ² = 0.04, P = 0.13). Conversely, OAI was more strongly associated with GA (r ² = 0.33, P < 0.0001) than PMA (r ² = 0.08, P = 0.036). For 28 infants with congenital structural anomalies that predispose to SDB (GA 38.0 ± 3.1 weeks, PMA 43.1 ± 3.3 weeks, AHI 37.7 ± 30, OAI 8.2 ± 11.8), neither AHI nor OAI were related to PMA or GA. Conclusions: Among infants who received clinically-indicated polysomnograms but did not have obvious structural risk for SDB, AHI declined with advancing PMA, but obstructive-apnea was best predicted by prematurity. In contrast, the SDB risk did not improve with increasing GA or PMA for infants with congenital structural risk factors; such infants may not outgrow their risk for SDB.