Short- and long-term outcomes of very low birth weight infants in Korea: Korean Neonatal Network update in 2019

Pediatric Extracorporeal Membrane Oxygenation in Korea: A Multicenter Retrospective Study on Utilization and Outcomes Spanning Over a Decade

BACKGROUND

Over the last decade, extracorporeal membrane oxygenation (ECMO) use in critically ill children has increased and is associated with favorable outcomes. Our study aims to evaluate the current status of pediatric ECMO in Korea, with a specific focus on its volume and changes in survival rates based on diagnostic indications.

METHODS

This multicenter study retrospectively analyzed the indications and outcomes of pediatric ECMO over 10 years in patients at 14 hospitals in Korea from January 2012 to December 2021. Four diagnostic categories (neonatal respiratory, pediatric respiratory, post-cardiotomy, and cardiac-medical) and trends were compared between periods 1 (2012-2016) and 2 (2017-2021).

RESULTS

Overall, 1065 ECMO runs were performed on 1032 patients, with the annual number of cases remaining unchanged over the 10 years. ECMO was most frequently used for post-cardiotomy (42.4%), cardiac-medical (31.8%), pediatric respiratory (17.5%), and neonatal respiratory (8.2%) cases. A 3.7% increase and 6.1% decrease in pediatric respiratory and post-cardiotomy cases, respectively, were noted between periods 1 and 2. Among the four groups, the cardiac-medical group had the highest survival rate (51.2%), followed by the pediatric respiratory (46.4%), post-cardiotomy (36.5%), and neonatal respiratory (29.4%) groups. A consistent improvement was noted in patient survival over the 10 years, with a significant increase between the two periods from 38.2% to 47.1% (P = 0.004). Improvement in survival was evident in post-cardiotomy cases (30-45%, P = 0.002). Significant associations with mortality were observed in neonates, patients requiring dialysis, and those treated with extracorporeal cardiopulmonary resuscitation (P < 0.001). In pediatric respiratory ECMO, immunocompromised patients also showed a significant correlation with mortality (P < 0.001).

CONCLUSION

Pediatric ECMO demonstrated a steady increase in overall survival in Korea; however, further efforts are needed since the outcomes remain suboptimal compared with global outcomes.

Spontaneous movements as prognostic tool of neurodevelopmental outcomes in preterm infants: a narrative review

An estimated 15 million infants are born prematurely each year. Although the survival rate of preterm infants has increased with advances in perinatal and neonatal care, many still experience various complications. Since improving the neurodevelopmental outcomes of preterm births is a crucial topic, accurate evaluations should be performed to detect infants at high risk of cerebral palsy. General movements are spontaneous movements involving the whole body as the expression of neural activity and can be an excellent biomarker of neural dysfunction caused by brain impairment in preterm infants. The predictive value of general movements with respect to cerebral palsy increases with continuous observation. Automated approaches to examining general movements based on machine learning can help overcome the limited utilization of assessment tools owing to their qualitative or semiquantitative nature and high dependence on assessor skills and experience. This review covers each of these topics by summarizing normal and abnormal general movements as well as recent advances in automatic approaches based on infantile spontaneous movements.

Optimal Protocols and Management of Clinical and Genomic Data Collection to Assist in the Early Diagnosis and Treatment of Multiple Congenital Anomalies

Standardized protocols have been designed and developed specifically for clinical information collection and obtaining trio genomic information from infants affected with congenital anomalies (CA) and their parents, as well as securing human biological resources. The protocols include clinical and genomic information collection on multiple CA that were difficult to diagnose using pre-existing screening methods. We obtained human-derived resources and genomic information from 138 cases, including 45 families of infants with CA and their parent trios. For the clinical information collection protocol, criteria for target patient selection and a consent system for collecting and utilizing research resources are crucial. Whole genome sequencing data were generated for all participants, and standardized protocols were developed for resource collection and manufacturing. We recorded the phenotype information according to the Human Phenotype Ontology term, and epidemiological information was collected through an environmental factor questionnaire. Updating and recording of clinical symptoms and genetic information that have been newly added or changed over time are significant. The protocols enabled long-term tracking by including the growth and development status that reflect the important characteristics of newborns. Using these clinical and genetic information collection protocols for CA, an essential platform for early genetic diagnosis and diagnostic research can be established, and new genetic diagnostic guidelines can be presented in the near future.

Prevalence of asthma in preterm and associated risk factors based on prescription data from the Korean National Health Insurance database

We retrospectively analyzed National Health Insurance claims data (January 2002-December 2018) to determine the asthma prevalence and risk factors among preterm infants born in Korea. Patients with asthma were defined as those with a history of asthma medication prescriptions at least twice per year with International Classification of Diseases, Tenth Edition codes J45 and J46. We enrolled 99,139 preterm infants. The prevalence of asthma among preterm and term infants was 32.7% and 26.9%, 21.2% and 19.1%, 6.7% and 5.9%, 2.0%, and 1.6%, and 2.4% and 1.6% at 2, 5, 10, 15, and 16 years of age, respectively. The relative risk (RR) of asthma in preterm infants was 1.1-fold that in female preterm infants. The RR of asthma medication prescriptions for infants with extreme prematurity was 1.92-fold that of infants with moderate/late pre-term status. Among preterm with bronchopulmonary dysplasia (BPD) and respiratory distress syndrome (RDS) without comorbidities, the RRs for the number of asthma medication prescriptions were 1.34 and 1.06, respectively. This study revealed a higher prevalence of asthma among preterm infants than that in term infants. Male sex, extreme prematurity, BPD, and RDS were identified as risk factors for asthma medication prescriptions in preterm infants.

Neurodevelopmental outcomes in very low birthweight infants with retinopathy of prematurity in a nationwide cohort study

In a nationwide prospective cohort of Korean infants with very low birthweights (VLBW, birth weight < 1500 g) from 70 neonatal intensive care units of the Korean Neonatal Network, we investigated neurodevelopmental outcomes in preterm infants with retinopathy of prematurity (ROP) from 2132 infants with VLBW who had undergone developmental assessments at 18–24 months of corrected age. Motor, cognitive, or language delay was determined using developmental scores that were less than 1 standard deviation from the average. Comparative analyses and multivariate regression analyses were performed to validate the association between ROP or its treatment and developmental delay. Motor (52.8% vs. 36.3%), cognitive (46.8% vs. 31.6%), and language delays (42.5% vs. 28.4%) were noted more frequently in infants with ROP than in those without ROP; this was statistically significant (all P < 0.001). Multivariate analyses showed that motor and cognitive delays were significantly associated with ROP. There were no remarkable differences between the neurodevelopmental outcomes and the treatment modalities (laser photocoagulation, anti-vascular endothelial growth factor injection, or both) for ROP, and both stratification and multivariate regression analyses confirmed no significant association between anti-vascular endothelial growth factor therapy and neurodevelopmental delay. As ROP is significantly associated with poor neurodevelopmental outcomes independent of extreme prematurity, neurodevelopmental functions should be given attention in infants with ROP.

Ophthalmic complications in retinopathy of prematurity in the first decade of life in Korea using the national health insurance database

The aim of this study is to investigate the epidemiology of ophthalmic complications of retinopathy of prematurity (ROP) after preterm birth using population-based database in South Korea. Using the National Health Insurance database, ophthalmic complications among premature infants born in 2007–2008 during their 10-year follow-up period were identified. Annual cumulative incidence rate and period prevalence of complications at each age were analyzed among those with ROP and those who underwent treatment for ROP (tROP). The hazard ratios (HRs) according to the presence of ROP and treatment for ROP were also analyzed. We identified 18,256 premature infants, 6995 of whom had ROP. The prevalence at 10th year for overall ophthalmic complications was 11.1% and 35.9% among ROP and tROP, respectively. Strabismus, amblyopia, and glaucoma were the three most common complications. The presence of ROP was associated with higher risk of complications (HR 1.53, 95%CI 1.44–1.61) among premature infants, and the presence of treatment for ROP was associated with higher risk of complications (HR 4.31, 95%CI 3.74–4.98) among ROP cases. This study reports the nationwide epidemiologic data on ophthalmic complications of ROP during the first decade of life, which will help advance our understandings and establish national strategies in managing ROP.

Short information: Bacterial meningitis in very low birthweight infants in Korea from 2013-2016

BACKGROUND

Neonatal bacterial meningitis (BM) has an incidence of 0.2-0.4 per 1,000 births and a mortality rate of 20-25%. Data from the Korean Neonatal Network (KNN) were evaluated to study the incidence, mortality, and risk factors associated with BM in very-low-birthweight (VLBW; <1,500 g) infants.

METHODS

We analyzed KNN data from 2013-2016 collected from 70 neonatal units.

RESULTS

The incidence of BM in VLBW infants was 40 out of 8,263 (0.5%). The 40 infants with BM had a mean gestational age of 27.1 ± 2.0 weeks and a mean birthweight of 1,036.8 ± 220.0 g. Mean age at diagnosis was 51.5 ± 38.3 days (range, 1-171). Infants with BM were divided into two groups: Group 1 (onset age ≤ 28 days) and Group 2 (onset age > 28 days). Coagulase-negative Staphylococcus (CONS) was the most common pathogen underlying meningitis in 11 of 40 cases (28%). BM co-occurred with bacteremia in 14 of 40) of cases (35%); bacteremia was significantly more common in Group 1 than Group 2 (P < 0.05). Seizure and intraventricular hemorrhage (≥grade 3) were significantly more prevalent in Group 2 than Group 1 (P < 0.05). The mortality rate of infants with BM was 4 out of 40 (10%), which was significantly lower than that of VLBW infants without BM (1,152/8,223, [14%]; P < 0.05).

CONCLUSIONS

The incidence of BM in VLBW infants was high, but the mortality rate was low. CONS was the most common pathogen of BM in VLBW infants.

Prevalence and Infant Mortality of Major Congenital Malformations Stratified by Birthweight

BACKGROUND

Low birthweight and major congenital malformations (MCMs) are key causes of infant mortality.

OBJECTIVES

The aim of this study was to explore the prevalence of MCMs in infants with low and very low birthweight and analyze the impact of MCMs and birthweight on infant mortality.

METHODS

We determined prevalence and infant mortality of 28 life-threatening MCMs in very-low-birthweight (<1,500 g, VLBW), low-birthweight (1,500-2,499 g, LBW), or normal-birthweight (≥2,500 g, NBW) infants in a cohort of 2,727,002 infants born in Germany in 2006-2017, using de-identified administrative data of the largest statutory public health insurance system in Germany.

RESULTS

The rates of VLBW, LBW, and NBW infants studied were 1.3% (34,401), 4.0% (109,558), and 94.7% (2,583,043). MCMs affected 0.5% (13,563) infants, of whom >75% (10,316) had severe congenital heart disease. The prevalence (per 10,000) of any/cardiac MCM was increased in VLBW (286/176) and LBW (244/143), as compared to NBW infants (38/32). Infant mortality rates were significantly higher in infants with an MCM, as opposed to infants without an MCM, in each birthweight group (VLBW 28.5% vs. 11.5%, LBW 16.7% vs. 0.9%, and NBW 8.6% vs. 0.1%). For most MCMs, observed survival rates in VLBW and LBW infants were lower than expected, as calculated from survival rates of VLBW or LBW infants without an MCM, and NBW infants with an MCM.

CONCLUSIONS

Infants with an MCM are more often born with LBW or VLBW, as opposed to infants without an MCM. Many MCMs carry significant excess mortality when occurring in VLBW or LBW infants.

Nonlinear relationship between early postnatal weight gain velocity and neurodevelopmental outcomes in very-low birth weight preterm infants: A secondary analysis based on a published prospective cohort study

BACKGROUND

Extrauterine growth restriction among the very-low birth weight preterm infants (VLBWPIs) is associated with poorer cognitive development outcome, while the rapid weight gain in infancy increases the long-term risk of obesity and noncommunicable disease among VLBWPIs. However, the results of research on the association between early postnatal growth velocity and neurodevelopmental outcomes in VLBWPIs are still limited and controversial.

OBJECTIVE

We aimed to explore the association between the growth velocity in early postnatal and neurodevelopmental impairment (NDI) among VLBWPIs.

METHODS

This study was a secondary analysis of a previously published prospective cohort. It was based on data on 1,791 premature infants with a birth weight of less than 1500 g, registered in the database of the Premature Baby Foundation of Taiwan between 2007 and 2011. A binary logistic regression model was used to evaluate the association between the weight gain velocity in different periods [from birth to 6 months corrected age (CA), 6 to 12 months CA, and 12 to 24 months CA] and NDI, respectively. The generalized additive model and the smooth curve fitting (penalized spline method) were used to address nonlinearity, and a two-piece-wise binary logistic regression model was added to explain the nonlinearity further.

RESULTS

Nonlinearities were observed between NDI and the weight gain velocity from birth to 6 months CA [inflection point 20.36, <inflection point: odds ratio (OR) = 0.75, 95% confidence interval (CI) 0.67-0.84, >inflection point: OR = 1.01, 95% CI 0.97-1.05], 6-12 months CA [inflection point 9.44, <inflection point: OR = 0.89, 95% CI 0.84-0.94, >inflection point: OR = 1.05, 95% CI 1.05-(1.00, 1.11)], and 12-24 months CA [inflection point 16.00, <inflection point: OR = 0.93, 95% CI 0.88-0.98, >inflection point: OR = 1.75, 95% CI 1.05-(0.96, 3.08)].

CONCLUSION

The neurodevelopmental benefits from a rapid weight gain velocity from birth to 24 months CA might be limited once the growth pace reaches an optimum level. It would help find a pattern of growth that facilitates optimal neurodevelopment, yet minimizes negative health consequences associated with overnutrition further.

Severe Retinopathy of Prematurity Associated With Neurodevelopmental Disorder in Children

OBJECTIVE

This study aimed to investigate whether severe retinopathy of prematurity (ROP) could be an association factor for neurodevelopmental disorders in premature infants without other risk factors-such as congenital anomalies, birth injuries, and neurological diseases-that may cause developmental delay.

METHODS

We used health claims data recorded between 2007 and 2018 in the Korean National Health Insurance Service (KNHIS) database. We recruited a total of 18,256 premature infant born between 2007 and 2008 without congenital anomaly or birth injury (with ROP 6,995, without ROP 11,261) and divided them into four groups as follows: Group A, 209 extremely premature infants [gestational age (GA) < 28] with mild ROP; Group B, 75 extremely premature infants (GA < 28) with severe ROP; Group C, 6,510 other premature infants (28 ≤ GA <37)with mild ROP; and Group D, 201 other premature infants (28 ≤ GA < 37) with severe ROP. Using regression analysis, we analyzed whether there was a correlation between ROP prevalence, severity, and developmental delay in premature infants without other risk factors.

RESULTS

The prevalence of developmental delay, according to GA and ROP severity, was higher in patients with severe ROP than in the other patients. The prevalence gradually decreased after birth. Among extremely premature infants with ROP, those with severe ROP had a 3.082-fold higher association with neurodevelopmental complications than those with mild ROP (p < 0.001). Compared with other premature infants with ROP, those with severe ROP had a 3.269-fold higher association with neurodevelopmental complications than those with mild ROP.

CONCLUSION

The severity of ROP may be associated with neurodevelopmental disorders in premature infants.

Retinopathy of Prematurity and Hearing Impairment in Infants Born with Very-Low-Birth-Weight: Analysis of a Korean Neonatal Network Database

Background: To investigate hearing impairment and its association with retinopathy of prematurity (ROP) among children born with very low birth weight (VLBW, birth weight < 1500 g). Methods: This prospective registry study included 7940 VLBW infants who underwent both ophthalmic (ROP) and hearing screening at the 70 participating centers of the Korean Neonatal Network. Hearing screening was performed using auditory brainstem response and/or automated otoacoustic emission testing. Hearing impairment, defined as a unilateral or bilateral hearing threshold of ≥40 dB on the auditory brainstem response threshold (ABR-T) test, was evaluated and compared between children with and without ROP at the corrected ages of 18 months and 3 years. Results: The frequency of infants who did not undergo hearing screening at near-term ages was higher in the ROP group than in the no-ROP group (18.2% vs. 12.0%, p < 0.001), and the prevalence of hearing impairment at 18 months was higher in the ROP group than in the no-ROP group (3.5% vs. 2.2%, p = 0.043). The prevalence of deafness was higher in children with ROP than those without ROP (0.4% vs. 0.1%, p = 0.049). There were significant differences in hearing impairment among the stages of ROP (p < 0.001). However, multivariate analyses and propensity score matching showed no significant association between ROP and hearing impairment at 18 months and 3 years after adjusting for prematurity-related variables (all p > 0.05). Conclusions: Among infants born with VLBW, hearing impairment was more common in those with ROP than in those without ROP at 18 months of age. However, there was no significant independent association between hearing impairment and ROP.

Current Status of Traditional Korean Medicine Services in Public Sector: A Study for Integrating Traditional Korean Medicine into Community Care System

Korea is currently executing a pilot program for community care of its aging population and aims to implement community care systems on a national scale by 2025. This study examines the traditional Korean medicine (TKM) service to be provided within community care by understanding the current status of TKM services. The Ministry of Health and Welfare (MoHW) sent official letters to 242 local governments (cities, districts, and counties) from October to November 2019 to survey the status of the public TKM services provided in 2018. The items of the survey included basic demographic information as well as information that could reveal how the program was implemented. In 112 local government jurisdictions (response rate 46.3%), a total of 867 TKM service programs were in place. As a result of the survey, it was revealed that they did not have any service manuals or evaluation results. To provide home-care-based TKM service for the elderly as an integrated part of a community care system, it is necessary to develop, distribute, and evaluate a standard service manual including an evaluation index by the central government.

Physiologic Changes during Sponge Bathing in Premature Infants

In this study, we observed physiological reactions of premature infants during sponge bathing in the neonatal intensive care unit (NICU). The infants’ body temperature, heart rate, and oxygen saturation were monitored to examine hypothermia risks during bathing. The participants of the study were 32 premature infants who were hospitalized right after their birth in the V hospital in Korea between December 2012 and August 2013. The informed consents of the study were received from the infants’ parents. The infants were randomly assigned into two-day and four-day bath cycle groups and their physiological reactions were monitored before bathing as well as 5 and 10 min after bathing. The collected data were analyzed using the SPSS statistical package through t-test. A significant drop in body temperature was noted in both groups; that is, 4-day bathing cycle and 2-day bathing cycle (p < 0.001). However, there were no significant changes in heart rate or transcutaneous oxygen levels. There was no significant change between groups at each measurement point. In order to minimize the physiological instability that may be caused during bathing, the care providers should try to complete bathing within the shortest possible time and to make bathing a pleasant and useful stimulus for infants.

Nationwide incidence and treatment pattern of retinopathy of prematurity in South Korea using the 2007-2018 national health insurance claims data

The aim of this study is to investigate the nationwide incidence and treatment pattern of retinopathy of prematurity (ROP) in South Korea. Using the population-based National Health Insurance database (2007–2018), the nationwide incidence of ROP among premature infants with a gestational age (GA) < 37 weeks (GA < 28 weeks, GA28; 28 weeks ≤ GA < 37 weeks; GA28-37) and the percentage of ROP infants who underwent treatment [surgery (vitrectomy, encircling/buckling); retinal ablation (laser photocoagulation, cryotherapy)] were evaluated. We identified 141,964 premature infants, 42,300 of whom had ROP, with a nationwide incidence of 29.8%. The incidence of ROP in GA28 group was 4.3 times higher than in GA28-37 group (63.6% [2240/3522] vs 28.9% [40,060/138,442], p < 0.001). As for the 12-year trends, the incidence of ROP decreased from 39.5% (3308/8366) in 2007 to 23.5% (2943/12,539) in 2018. 3.0% of ROP infants underwent treatment (25.0% in GA28; 1.7% in GA28-37); 0.2% (84/42,300) and 2.9% (1214/42,300) underwent surgery and retinal ablation, respectively. The overall percentage of ROP infants who underwent treatment has decreased from 4.7% in 2007 to 1.8% in 2018. This first Korean nationwide epidemiological study of ROP revealed a decreased incidence of ROP and a decreased percentage of ROP infants undergoing conventional treatment during a 12-year period.