This study aimed to elaborate upon prior findings suggestive of the altered lateralization of structural connectivity in the developing preterm brain by using diffusion tensor imaging tractography to explore how network topological asymmetries in fronto-limbic neural circuitry are altered at 36–41 weeks, postmenstrual age in 64 preterm infants without severe brain injury and 33 term-born infants. We compared the pattern of structural connectivity and network lateralization of the betweenness centrality in the medial fronto-orbital gyrus, superior temporal gyrus, amygdala, and hippocampus—the structures comprising the fronto-limbic brain circuit—between preterm and term infants. Global efficiency, local efficiency, and small-world characteristics did not differ significantly between the two hemispheres in term-born infants, suggesting that integration and segregation are balanced between the left and right hemispheres. However, the preterm brain showed significantly greater leftward lateralization of small-worldness (P = 0.033); the lateralization index of the betweenness centrality revealed that the medial fronto-orbital gyrus (P = 0.008), superior temporal gyrus (P = 0.031), and hippocampus (P = 0.028) showed significantly increased leftward asymmetry in preterm infants relative to term-infants independent of sex, age at imaging, and bronchopulmonary dysplasia. The altered lateralization of fronto-limbic brain circuitry might be involved in the early development of social–emotional disorders in preterm infants.

Background: Necrotizing enterocolitis (NEC) is a devastating disease in preterm infants with significant morbidities, including neurodevelopmental impairment (NDI). This study aimed to investigate whether NEC is associated with (1) brain volume expansion and white matter maturation using diffusion tensor imaging analysis and (2) NDI compared with preterm infants without NEC. Methods: We included 86 preterm infants (20 with NEC and 66 without NEC) with no evidence of brain abnormalities on trans-fontanelle ultrasonography and magnetic resonance imaging at term-equivalent age (TEA). Regional brain volume analysis and white matter tractography were performed to study brain microstructure alterations. NDI was assessed using the Bayley Scales of Infant and Toddler Development-III (BSID-III) at 18 months of corrected age (CA). Results: Preterm infants with NEC showed significantly high risk of motor impairment (odds ratio 58.26, 95% confidence interval 7.80–435.12, p < 0.001). We found significantly increased mean diffusivity (MD) in the splenium of corpus callosum (sCC) (p = 0.001) and the left corticospinal tract (p = 0.001) in preterm infants with NEC. The sCC with increased MD showed a negative association with the BSID-III language (p = 0.025) and motor scores (p = 0.002) at 18 months of CA, implying the relevance of sCC integrity with later NDI. Conclusion: The white matter microstructure differed between preterm infants with and without NEC. The prognostic value of network parameters of sCC at TEA may provide better information for the early detection of NDI in preterm infants.

Cystic periventricular leukomalacia (cPVL) is a major brain injury involving periventricular white matter that leads to neurodevelopmental impairment in very-low-birth weight (VLBW) infants. We investigated the neurodevelopmental outcomes (motor, cognition, visual, and hearing) of 5734 VLBW infants born between 2013 and 2019 and enrolled in the Korean Neonatal Network. Cranial ultrasound results were stratified by the presence of cPVL and severity of intraventricular hemorrhage (IVH) (no, low-grade [I/II], high-grade [III]). Neurodevelopmental impairment was evaluated using cerebral palsy for motor and Bayley Scales of Infant Development for cognition. cPVL was associated with motor, cognitive, and visual impairments in those without IVH and with low-grade IVH in pairwise comparisons (Cochran–Mantel–Haenszel p < 0.001). Conversely, cPVL was non-significantly correlated with cognitive impairment in high-grade IVH. In regression models adjusted for neonatal variables, isolated cPVL was strongly associated with motor (22.04; 11.39–42.63) and cognitive (3.10; 1.54–6.22) impairments. This study underlines the overall considerable significance of cPVL on NDI with divergent impacts depending on the severity of IVH and developmental indices.

Research on the quantification of hyperactivity in youth with attention-deficit/hyperactivity disorder (ADHD) has been limited and inconsistent. The purpose of this study was to test the discriminative value of impulse-radio ultra-wideband (IR-UWB) radar for monitoring hyperactive individuals with ADHD and healthy controls (HCs). A total of 10 ADHD patients and 15 HCs underwent hyperactivity assessment using IR-UWB radar during a 22-min continuous performance test. We applied functional ANOVA to compare the mean functions of activity level between the 2 groups. We found that the mean function of activity over time was significantly different and that the activity level of the ADHD group slightly increased over time with high dispersion after approximately 7 min, which means that the difference in activity level between the two groups became evident at this period. Further studies with larger sample sizes and longer test times are warranted to investigate the effect of age, sex, and ADHD subtype on activity level function.

Neurodevelopmental disorder (NDD) in preterm infants has become of great interest. We aimed to investigate the impact of preterm birth on the proportion of NDD using nationwide data provided by the Korean National Health Insurance Service. We included 4894 extremely preterm or extremely low-birth-weight (EP/ELBW; <28 weeks of gestation or birth weight < 1000 g) infants, 70,583 other preterm or low-birth-weight (OP/LBW; 28–36 weeks of gestation or birth weight < 2500 g) infants, and 264,057 full-term infants born between 2008 and 2015. We observed their neurodevelopment until 6 years of age or until the year 2019, whichever occurred first. Diagnoses of NDDs were based on the World Health Organization’s International Classification of Diseases 10th revision. An association between preterm birth and NDD was assessed using a multivariable logistic regression model. There was a stepwise increase in the risk of overall NDD with increasing degree of prematurity, from OP/LBW (adjusted odds ratio 4.46; 95% confidence interval 4.34–4.58), to EP/ELBW (16.15; 15.21–17.15). The EP/ELBW group was strongly associated with developmental delay (21.47; 20.05–22.99), cerebral palsy (88.11; 79.89–97.19), and autism spectrum disorder (11.64; 10.37–13.06). Preterm birth considerably increased the risk of NDD by the degree of prematurity.

Asthma and atopic dermatitis (AD) are representative chronic diseases in childhood. This study aimed to investigate the impact of preterm birth on the incidence and severity of asthma and AD in children, as well as to identify neonatal risk factors for asthma and AD. We used health claims data recorded between 2007 and 2014 in the Korean National Health Insurance Service database. We recruited 2,224,476 infants born between 2007 and 2014 and divided them into three groups: 3518 of extremely preterm (EP) infants (< 28 weeks of gestational age (GA)), 82,579 of other preterm (OP) infants (28–36 weeks of GA), and 2,138,379 of full-term (FT) infants (> 37 weeks of GA). We defined asthma as > 3 episodes of clinical visits in a year before 6 years of age, early asthma as onset at < 2 years of age, and severe asthma as > 1 event of status asthmaticus or admission to a hospital via an emergency room. AD was defined as ≥ 3 diagnoses in a year before 6 years of age, early AD as onset at < 2 years of age, and severe AD as prescription of high-potency topical steroids or immunosuppressants. An association of preterm birth with asthma and AD was assessed using inverse probability of treatment-weighted multivariable Cox regression analysis. Cardiorespiratory conditions, such as respiratory distress syndrome, bronchopulmonary dysplasia, patent ductus arteriosus, and pulmonary hypertension, significantly increased the risk of asthma. Specifically, bronchopulmonary dysplasia emerged as a significant risk factor for both severe and early-onset asthma (odds ratio (OR) 1.36, 95% CI 1.21–1.37 for severe asthma; OR 1.55, 95% CI 1.30–1.85 for early asthma), while it was associated with a decreased risk of AD (OR 0.86, 95% CI 0.80–0.92). Neonatal sepsis, jaundice, and retinopathy of prematurity were also identified as significant risk factors for later asthma. A stepwise increase in the risk of asthma with an increasing degree of prematurity was observed, with the OP group showing an adjusted hazard ratio (aHR) of 1.24 (95% CI: 1.22–1.26) and the EP group showing an aHR of 1.51 (95% CI: 1.41–1.63). Conversely, preterm birth was inversely associated with the risk of AD, with aHRs of 0.73 (95% CI: 0.67–0.79) for the OP group and 0.88 (95% CI: 0.87–0.89) for the EP group. Conclusion Preterm children have a significantly higher risk of asthma and lower risk of AD, with cardiorespiratory conditions significantly increasing the risk of asthma. Thus, we highlight the need for targeted respiratory management strategies for this high-risk population. What is Known: •Asthma and atopic dermatitis are prevalent chronic diseases in childhood, reducing the quality of life of children. •Preterm birth was associated with an increased risk of asthma, but few large nationwide studies. •Research on the relationship between preterm birth and pediatric atopic dermatitis is controversial, with few large nationwide studies. What is New: • Preterm children, especially born before 28 weeks of gestational age, had a significantly higher risk of asthma and lower risk of atopic dermatitis. • Cardiorespiratory comorbidities such as RDS, BPD, PDA, and pulmonary hypertension in neonatal period are prominent risk factors for asthma. • Preterm children are vulnerable to both early-onset and severe asthma.