P2.141: Sleep-Related Breathing Disorders Beyond Infancy Following Myelomeningocele Repair

Background: Children with myelomeningocele are at increased risk for sleep-related breathing disorders (SRBD), however current guidelines do not include formal evaluation with polysomnography (PSG). Previous studies described abnormal respiratory outcomes in infants with repaired myelomeningocele. We hypothesize that after 1 year of age there is 1) improvement of SRBD, 2) no need for oxygen requirement, and 3) no significant difference in SRBD presentation between prenatally vs. postnatally repaired groups.

Methods: Retrospective chart review of 57 patients with repaired myelomeningocele seen at Children’s Hospital Los Angeles between 2015–2024 who had PSG after age 1 year. Demographics, surgery type, medical conditions, PSG results, and oxygen requirement were collected.

Results: Of 57 subjects, 32 were male. 31/57 had PSG before age 1 year (age 4.6±6.2 weeks). 25/31 had central sleep apnea (CSA; central apnea index (CAI) 14.8±12.6). All had obstructive sleep apnea (OSA; obstructive apnea-hypopnea index (OAHI) 24.3±22.6). All required supplemental oxygen. 26/57 had PSG after 1 year of age (8.8±5.4 years). 4/26 had CSA (CAI 6.9±2.4), 23/26 had OSA (OAHI 13.3±13.5). 7/26 required supplemental oxygen. CSA (p <.001), CAI (p=.009), OAHI (p=.03), and supplemental oxygen use (p <.001) were decreased after 1 year of age. There was no difference in OSA prevalence (p=.09). Of the subjects with PSG before and after 1 year of age, 16/25 continued to have CSA, 26/31 continued to have OSA, and 22/31 continued to require supplemental oxygen. CAI decreased from 12.3±12.4 to 5.9±3.7 (p=.01) and OAHI decreased from 24.3±22.6 to 5.8±5.9 (p <.001). Oldest age of continued supplemental oxygen was 2.9±1.8 years. 16 subjects had prenatal repair and 41 had postnatal repair of myelomeningocele. In the prenatal repair group, 8 had CSA (CAI 8.9±3.4), 13 had OSA (OAHI 8.1±6.8), and 10 required supplemental oxygen. In the postnatal repair group, 12 had CSA (CAI 7.7±3.0), 36 had OSA (OAHI 10.1±11.8), and 19 required supplemental oxygen. There were no differences between prenatally and postnatally repaired groups. There were no differences in CSA or OSA between groups with body mass index (BMI) below the 85th percentile and above the 85th percentile.

Conclusion: In patients with repaired myelomeningocele, while CSA and oxygen requirements decreased in prevalence after 1 year of age, OSA persisted, and the majority still had SRBD. BMI did not affect presence of SRBD. There was no difference between those prenatally vs. postnatally repaired. Our findings highlight the importance of continued surveillance with PSG in this population.