0863 Multidimensional Determinants of Pediatric OSA Severity: Baseline Cross-Sectional Analysis of Clinical and Anatomical Factors

Abstract Introduction To characterize pediatric obstructive sleep apnea (OSA) and identify the major determinants of anatomical and sleep-related factors associated with its severity. Methods A total of 79 pediatric patients with OSA diagnosed between May 2023 and December 2024 were included. Clinical characteristics, anatomical indices and sleep breathing habits were collected. Craniofacial and three-dimensional upper airway measurements were obtained via cone-beam computed tomography, with nasal resistance measured by NR6 Rhinomanometry. Group and within-group analyses were performed, followed by spearman correlation and multiple regression. Results Pediatric patients aged 3-14 years (40 females and 39 males; 44.3% with attention deficit disorders/attention deficit hyperactivity disorder (ADD/ADHD) symptoms or diagnosis) were classified as 22 mild, 36 moderate and 21 severe OSA, with no significant age differences among severity groups. Sleep study results showed that apnea duration variability index (ADVI) progressively increased from mild to moderate and severe groups (P=0.000), and rapid eye movement (REM) ratio similarly rose with OSA severity (P =0.001). Among anatomical indices, minimum airway area differed across groups (P=0.01), while overjet ratio was notably higher in severe cases among three groups (P=0.04). Spearman correlation analysis showed that 3%AHI was positively significantly associated with REM ratio, sleep fragmentation, AVDI, brachyfacial pattern, and oxygen-related indices (MinSpO2, MaxSpO2), as well as with 3% and 4% respiratory disturbance index (RDI) and oxygen desaturation index (ODI) measures (all P< 0.05). Higher AVDI was also linked to poorer school performance, more nocturnal awakenings and transitions, and longer total sleep time (all P< 0.05). Further multiple linear regression analysis was conducted to explore the potential factors to AHI. The model was significant (F=8.97, P=0.001, adjust R2=0.55). After adjusting for age, gender, and BMI using a stepwise approach, the ADVI (β=5.85, P=0.02), REM ratio (β=18.99, P=0.03) and soft palate length (β=0.79, P=0.002) remained a significantly positive effect to 3%AHI. Conclusion Elevated ADVI and REM ratio, and longer soft palate length were independently associated with higher 3%AHI. In addition, ADVI was also correlated with poorer learning and increased nocturnal wake transitions. This highlights their potential roles in assessing OSA severity, especially in pediatric patients with ADD/ADHD. Support (if any) Supported by Vivos Therapeutics, Inc.