McCaffery, Harlan

BACKGROUND & OBJECTIVE Sleep-disordered breathing (SDB) may be a remediable contributor to abnormal cognitive outcomes for children with myelomeningocele. We investigated the frequency of SDB among neonates with fetal vs postnatal myelomeningocele repair. METHODS In this nine-center, prospective, observational study, neonates with myelomeningocele born at more than 30 weeks gestational age underwent a 10-hour bedside polysomnogram at at least 35 weeks postmenstrual age, before hospital discharge. The primary outcome was SDB severity, reflected by the apnea-hypopnea index (AHI; number of respiratory events per hour of sleep). Decisions regarding surgical timing (fetal vs postnatal), technique (open fetal vs fetoscopic approach), and SDB treatment were made by the clinical teams. RESULTS Among 173 infants, 92/173 (53%) had SDB (median AHI 22.5, IQR 12.2–44.2). In unadjusted analysis, AHI was higher among the 90 neonates with fetal repair vs 83 with postnatal surgery (median 29, IQR 14–49, vs 19, IQR 10–36, P = .008). In propensity-adjusted multivariable models, prematurity was independently associated with AHI, whereas surgical timing (fetal vs postnatal) was not. Hindbrain herniation, myelomeningocele level, and clinical need for ventriculoperitoneal shunt did not predict AHI in adjusted models. Supplemental oxygen was commonly prescribed, for 44% of fetal vs 39% of postnatal myelomeningocele repair infants (P = .5). CONCLUSIONS SDB affects more than half of neonates with myelomeningocele. The higher AHI after fetal surgery could stem from the elevated incidence of prematurity in this group. As SDB is treatable and has a potential impact on neurodevelopment, routine screening could become an integral part of a strategy to optimize long-term medical and neurodevelopmental outcomes.

Abstract Introduction A prospective, longitudinal, multicenter study was designed to test the hypothesis that sleep-disordered breathing (SDB) is ubiquitous among newborns with myelomeningocele (MMC). We evaluated variability in polysomnography (PSG) scoring and interpretation. Methods Nine US pediatric centers participated. Neonates with MMC born at >30 weeks gestation underwent bedside PSG at ≥35 weeks postmenstrual age, before hospital discharge. PSGs were scored by registered technologists (RPSGTs) at each site using AASM Scoring Manual infant criteria and interpreted by a board-certified sleep medicine physician (BCSMP). A single, central RPSGT blinded to clinical outcomes then re-scored all PSGs. One of two pediatric BCSMPs reviewed each study; the two BCSMPs jointly determined diagnoses for consensus central reports. Differences in scoring and overall PSG interpretation were evaluated with kappa and intraclass correlation coefficients (ICC). Results For 110 neonates with MMC, the median apnea-hypopnea index (AHI) was 26.5 [11.3-43.3] as reported by sites, and 23.0 [IQR 13.0-44.8] as reported centrally (к 0.81). The central apnea index (CAI) was also scored similarly by sites (3.3 [0.9-7.0]) and centrally (2.6 [0.6-7.3]; к 0.88), as were hypopneas (15.2 [7.5;26.9]) and 14.1 [6.4;27.9]; к 0.82). However, the obstructive apnea index (OAI) was reported to be much higher by sites (10.0 [1.9-29.1]) than centrally (1.5 [0.5 – 4.1]; к 0.29). Moreover, overall PSG interpretation differed between sites and central reviewers. Obstructive sleep apnea (OSA) was reported as a diagnosis by sites for 57.6% of neonates, vs. 10.9% by central review (ICC 0.06); central sleep apnea was reported by sites for 26.6% of neonates, vs. 14.5% by central review (ICC 0.50). When hypopneas were the most prevalent respiratory events, central review favored a less specific diagnosis of sleep-disordered breathing. Conclusion Considerable variability in scoring of obstructive apneas, and in polysomnography-based diagnoses, may exist for neonates. Sites may have designated hypopneas as obstructive, driving the diagnosis of OSA, while central review noted equivocal features of neonatal hypopneas, leading to a less specific diagnosis of sleep-disordered breathing. Further work to develop infant respiratory scoring rules, and diagnostic criteria, and to evaluate their clinical use may be warranted. Support (if any) This study is supported by NIH (R01 HL147261).

In breastfed infants, human milk provides the primary source of iodine to meet demands during this vulnerable period of growth and development. Iodine is a key micronutrient that plays an essential role in hormone synthesis. Despite the importance of iodine, there is limited understanding of the maternal factors that influence milk iodine content and how milk iodine intake during infancy is related to postnatal growth. We examined breast milk samples from near 2 weeks and 2 months post-partum in a mother-infant dyad cohort of mothers with pre-pregnancy weight status defined by body mass index (BMI). Normal (NW, BMI < 25.0 kg/m2) is compared to overweight/obesity (OW/OB, BMI ≥ 25.0 kg/m2). The milk iodine concentration was determined by inductively coupled plasma mass spectrometry. We evaluated the associations between iodine content at 2 weeks and infant anthropometrics over the first year of life using multivariable linear mixed modeling. Iodine concentrations generally decreased from 2 weeks to 2 months. We observed no significant difference in iodine based on maternal weight. A higher iodine concentration at 2 weeks was associated with a larger increase in infant weight-for-age and weight-for-length Z-score change per month from 2 weeks to 1 year. This pilot study shows that early iodine intake may influence infant growth trajectory independent of maternal pre-pregnancy weight status.