Obstructive sleep apnea in 12 to 24 months old toddlers referred for sleep study in a tertiary care center.

Objective: To assess OSA prevalence, comorbidities, and the influence of sleep stages and body positions on respiratory events distribution in toddlers aged 12-24 months.

Methods: A single center retrospective study that included toddlers aged 12-24 months old who underwent overnight PSG. OSA severity was categorized by obstructive apnea-hypopnea index (OAHI) as mild (1-4.9 events/h), moderate (5-9.9 events/h), and severe (≥ 10 events/h).

Results: 283 PSG data were included with a median age of 18 months (IQR 16-20.25) for the OSA group (168/283) and 19 months (IQR 16-22) for the non-OSA group (115/283) (p = 0.047). OSA prevalence was 68.5% (42.3% mild, 18.5% moderate, and 39% severe). 38.1% of children had no comorbidities, 24.4% had a history of prematurity and 11.3% had Down syndrome. Multivariate binominal regression analysis showed that children with history of prematurity (p = 0.017) and Down syndrome (p = 0.043) had higher odds of having OSA. The mean SaO2 in REM sleep was lower, and the mean time spent with oxygen saturation below 90% was higher in children with neuromuscular disease compared to those with other comorbidities. In toddlers without comorbidities, the median REM OAHI was 29.8 events/h (IQR: 58.48), whereas the median non-REM OAHI was 4.1 events/h (IQR: 10.4 p < 0.001). Supine OAHI was 7.9 (IQR: 24.9), and off supine OAHI was 10.5 (IQR: 18.1, p = 0.407).

Conclusions: In toddlers aged 12-24 months, history of prematurity and Down syndrome were significantly associated with OSA. Obstructive respiratory events occurred predominantly in REM sleep, and no significant positional relations were noted.