Demographic transition in South Korea: implications of falling birth rates.

This review examines the critical issues of declining total fertility rates (TFRs) and aging populations in East Asia with special focus on South Korea. It provides a comprehensive analysis of TFR trends, aging demographics, and the policy responses of these nations to the low-fertility crisis. This study highlights the intricate tapestry of the factors contributing to these demographic shifts, including economic, social, and cultural influences. It also examines the effectiveness of various prenatal policies implemented across these countries, offering insight into their successes and limitations. Furthermore, it explores the role of immigration as a potential solution to the structural challenges posed by low birth rates. This review underscores the importance of multifaceted strategies for addressing the complex demographic challenges faced by South Korea.

The Application of Virtual Reality in Shoulder Surgery Rehabilitation.

To achieve a positive functional prognosis in orthopedic surgery, particularly in shoulder surgeries, effective rehabilitation is essential. Recently, there has been growing interest in the use of virtual reality (VR) in the field of orthopedics, particularly for preoperative education and training, as well as clinical and home-based rehabilitation. This report describes the process of developing an application utilizing Meta Quest 2 VR technology (Meta, CA, USA) for rehabilitation after shoulder surgery. This application assists patients in performing postoperative exercises at home by wearing VR equipment tailored to their postoperative weeks. The advantages of VR rehabilitation lie in overcoming the limitations of traditional rehabilitation methods and providing patients with a better rehabilitation experience. Moreover, automating the rehabilitation process and reducing patients' visits to clinics can lead to cost savings. This report raises expectations for the potential and scalability of VR utilization, extending beyond orthopedics to other fields. In addition, it anticipates that with better feedback and motivation, the rehabilitation effects for patients can be further enhanced.

Evaluating Novel SP-B and SP-C Synthetic Analogues for Pulmonary Surfactant Efficacy.

Pulmonary surfactants, a complex assembly of phospholipids and surfactant proteins such as SP-B and SP-C, are critical for maintaining respiratory system functionality by lowering surface tension (ST) and preventing alveolar collapse. Our study introduced five synthetic SP-B peptides and one SP-C peptide, leading to the synthesis of CHAsurf candidates (CHAsurf-1 to CHAsurf-5) for evaluation. We utilized a modified Wilhelmy balance test to assess the surface tension properties of the surfactants, measuring spreading rate, surface adsorption, and ST-area diagrams to comprehensively evaluate their performance. Animal experiments were performed on New Zealand white rabbits to test the efficacy of CHAsurf-4B, a variant chosen for its economic viability and promising ST reduction properties, comparable to Curosurf®. The study confirmed that higher doses of SP-B in CHAsurf-4 are associated with improved ST reduction. However, due to cost constraints, CHAsurf-4B was selected for in vivo assessment. The animal model revealed that CHAsurf-4B could restore alveolar structure and improve lung elasticity, akin to Curosurf®. Our research highlights the significance of cysteine residues and disulfide bonds in the structural integrity and function of synthetic SP-B analogues, offering a foundation for future surfactant therapy in respiratory disorders. This study's findings support the potential of CHAsurf-4B as a therapeutic agent, meriting further investigation to solidify its role in clinical applications.

Nationwide Long-Term Growth and Developmental Outcomes of Infants for Congenital Anomalies in the Digestive System and Abdominal Wall Defects With Surgery in Korea.

BACKGROUND: Infants with congenital anomalies of the digestive system and abdominal wall defects requiring surgery are at risk of growth and developmental delays. The aim of this study was to analyze long-term growth and developmental outcomes for infants with congenital anomalies of the digestive system and abdominal wall defects who underwent surgery in Korea. METHODS: We extracted data from the Korean National Health Insurance Service database for the years 2013-2019. Major congenital anomalies were defined according to the International Classification of Diseases-10 and surgery insurance claim codes. The χ² test and the Cochran-Armitage trend test were performed for data analysis. RESULTS: A total of 4,574 infants with major congenital anomalies in the digestive system and abodminal wall defects, who had undergone surgey, were reviewed. Anorectal obstruction/stenosis was the most prevalent anomaly (4.9 per 10,000 live births). The prevalence of congenital anomalies of the digestive system was 15.5 per 10,000 live births, and that of abdominal wall defects was 1.5 per 10,000 live births. Seven percent of infants with congenital anomalies in the digestive system died, of which those with diaphragmatic hernia had the highest mortality rate (18.8%). Among 12,336 examinations at 6, 12, 24, 36, 48, 60, and 72 months of age, 16.7% showed a weight below the 10th percentile, 15.8% had a height below the 10th percentile, and 13.2% had a head circumference below the 10th percentile. Abnormal developmental screening results were observed in 23.0% of infants. Infants with esophageal atresia with/without tracheoesophageal fistula most often had poor growth and development. Delayed development and cerebral palsy were observed in 490 (10.7%) and 130 (2.8%) infants respectively. Comparing the results of infants born in 2013 between their 24- and 72-month health examinations, the proportions of infants with poor height and head circumference growth increased by 6.5% and 5.3%, respectively, whereas those with poor weight growth and abnormal developmental results did not markedly change between the two examinations. CONCLUSION: Infants with congenital anomalies of the digestive system and abdominal wall defects exhibit poor growth and developmental outcomes until 72 months of age. Close monitoring and careful consideration of their growth and development after discharge are required.

Major Congenital Anomalies in Korean Livebirths in 2013-2014: Based on the National Health Insurance Database.

BACKGROUND: In Korea, there have been no reports comparing the prevalence of major congenital anomalies with other countries and no reports on surgical treatment and long-term mortality. We investigated the prevalence of 67 major congenital anomalies in Korea and compared the prevalence with that of the European network of population-based registries for the epidemiological surveillance of congenital anomalies (EUROCAT). We also investigated the mortality and age at death, the proportion of preterm births, and the surgical rate for the 67 major congenital anomalies. METHODS: Korean National Health Insurance claim data were obtained for neonates born in 2013-2014 and admitted within one-year-old. Sixty-seven major congenital anomalies were defined by medical diagnoses classified by International Classification of Diseases-10 codes according to the EUROCAT definition version 2014. Mortality and surgery were defined if any death or surgery claim code was confirmed until 2020. Poisson distribution was used to calculate the 95% confidence interval of the congenital anomaly prevalence. RESULTS: The total prevalence of the 67 major anomalies was 433.5/10,000 livebirths. When compared with the prevalence of each major anomaly in EUROCAT, the prevalence of spina bifida, atrial septal defect (ASD), congenital megacolon, hip dislocation and/or dysplasia and skeletal dysplasia were more than five times higher in Korea. In contrast, the prevalence of aortic atresia/interrupted aortic arch and gastroschisis was less than one-fifth in Korea. The proportion of preterm births was 15.7%; however, more than 40% of infants with anencephaly, annular pancreas and gastroschisis were preterm infants. Additionally, 29.2% of the major anomalies were admitted to the neonatal intensive care units at birth, and 25.6% received surgical operation. The mortality rate was 1.7%, and 78.2% of the deaths occurred within the first year of life. However, in neonates with tricuspid valve atresia and stenosis, duodenal atresia or stenosis, and diaphragmatic hernia, more than half died within their first month of life. ASD and ventricular septal defect were the most common anomalies, and trisomy 18 and hypoplastic left heart syndrome were the most fatal anomalies. All infants with aortic atresia/interrupted aortic arch and conjoined twins received surgery. CONCLUSION: The proportion of surgeries, preterm births and mortality was high in infants with major congenital anomalies. The establishment of a national registry of congenital anomalies and systematic support by national medical policies are needed for infants with major congenital anomalies in Korea.

Effects of A Single Balance Training Session on Neural Excitability in Individuals With Chronic Ankle Instability.

CONTEXT: Individuals with chronic ankle instability (CAI) demonstrate reduced spinal reflex modulation and corticospinal excitability of the soleus, which may contribute to decreased balance performance. OBJECTIVE: To determine the effects of a single session of balance training on Spinal-reflexive excitability modulation and corticospinal excitability in those with CAI. DESIGN: Randomized controlled trials. SETTING: Research laboratory. PARTICIPANTS: Thirty participants with CAI were randomly assigned to the balance training (BAL) or control (CON) group. MAIN OUTCOME MEASURES: Modulation of soleus spinal-reflexive excitability was measured by calculating relative change in normalized Hoffmann reflexes (ratio of the H-reflex to the M-wave) from prone to single-leg standing. Corticospinal excitability was assessed during single-leg stance using transcranial magnetic stimulation, outcomes of which included active motor threshold (AMT), motor evoked potential, and cortical silent period (CSP). Balance performance was measured with center of pressure velocity in anterior to posterior and medial to lateral directions. Separate 2 × 2 repeated-measures analyses of variance were employed to determine the effect of group (BAL and CON) and time (baseline and posttraining) on each dependent variable. RESULTS: There were significant group by time interactions in the modulation of soleus spinal-reflexive excitability (F1,27 = 4.763, P = .04); CSP at 100% AMT (F1,27 = 4.727, P = .04); and CSP at 120% AMT (F1,27 = 16.057, P < .01). A large effect size suggests increased modulation of spinal-reflexive excitability (d = 0.81 [0.03 to 1.54]) of the soleus in BAL compared with CON at posttest, while CSP at 100% (d = 0.95 [0.17 to 1.70]) and 120% AMT (d = 1.10 [0.29 to 1.84]) was reduced in BAL when compared with CON at posttest. CONCLUSION: After a single session of balance training, individuals with CAI initiated increases in spinal reflex modulation and corticospinal excitability of the soleus. Thus, individuals with CAI who undergo balance training exhibit positive neural adaptations that are linked to improvements in balance performance.

Artificial Intelligence-Driven Respiratory Distress Syndrome Prediction for Very Low Birth Weight Infants: Korean Multicenter Prospective Cohort Study.

BACKGROUND: Respiratory distress syndrome (RDS) is a disease that commonly affects premature infants whose lungs are not fully developed. RDS results from a lack of surfactant in the lungs. The more premature the infant is, the greater is the likelihood of having RDS. However, even though not all premature infants have RDS, preemptive treatment with artificial pulmonary surfactant is administered in most cases. OBJECTIVE: We aimed to develop an artificial intelligence model to predict RDS in premature infants to avoid unnecessary treatment. METHODS: In this study, 13,087 very low birth weight infants who were newborns weighing less than 1500 grams were assessed in 76 hospitals of the Korean Neonatal Network. To predict RDS in very low birth weight infants, we used basic infant information, maternity history, pregnancy/birth process, family history, resuscitation procedure, and test results at birth such as blood gas analysis and Apgar score. The prediction performances of 7 different machine learning models were compared, and a 5-layer deep neural network was proposed in order to enhance the prediction performance from the selected features. An ensemble approach combining multiple models from the 5-fold cross-validation was subsequently developed. RESULTS: Our proposed ensemble 5-layer deep neural network consisting of the top 20 features provided high sensitivity (83.03%), specificity (87.50%), accuracy (84.07%), balanced accuracy (85.26%), and area under the curve (0.9187). Based on the model that we developed, a public web application that enables easy access for the prediction of RDS in premature infants was deployed. CONCLUSIONS: Our artificial intelligence model may be useful for preparations for neonatal resuscitation, particularly in cases involving the delivery of very low birth weight infants, as it can aid in predicting the likelihood of RDS and inform decisions regarding the administration of surfactant.

Birth Rate Transition in the Republic of Korea: Trends and Prospects.

BACKGROUND: In Korea, the birth rate is declining at an alarming pace. This study aimed to investigate the changes and trends in the population count, number of births, and birth rate in Korea, in the past and future. METHODS: Data regarding the total number of births, crude birth rate, and total fertility rate were collected from the "Statistics Korea Census" of the national statistical portal, census report, and Statistics Korea's "2020 Population Trend Survey for 1981-2020, provisional results of birth and death statistics." We used the Organisation for Economic Co-operation and Development 2019 Family Database for the TFR. To develop a better understanding of the data in this study, we classified it according to the modern history of Korea. RESULTS: The changes and trends in the number of births and fertility rate in Korea, after liberation, were due to the birth control policy that restricted births. In Korea's low fertility society, which began in the mid-2000s, the fertility rate dropped to below 0.84 in 2020, despite policies to improve the quality of the population. The death toll has reached 300,000, entering an era of population decline. CONCLUSION: As we enter the era of population decline, we are in a direction that will cause various socioeconomic problems, from demographic problems to future population decline.

Cross-Education Balance Effects After Unilateral Rehabilitation in Individuals With Chronic Ankle Instability: A Systematic Review.

OBJECTIVE: To conduct a systematic review of existing literature on cross-education balance effects after unilateral training in the population with chronic ankle instability (CAI). DATA SOURCES: PubMed, SPORTDiscus, CINAHL Plus. STUDY SELECTION: To be included in the systematic review, studies were required to have been published in English, included participants with CAI, had participants undergo a unilateral therapeutic exercise for the lower extremity, and measured balance performance of the untrained lower extremity before and after the intervention. DATA EXTRACTION: The certainty of evidence in each included study was assessed via the Downs and Black checklist. A score of 24 to 28 indicated excellent or very low risk of bias; 19 to 23, good or low risk of bias; 14 to 18, fair or moderate risk of bias; and <14, poor or high risk of bias. We extracted information from each study regarding design, participant characteristics, inclusion criteria, independent and dependent variables, intervention, and results. Baseline and postintervention balance performance data for participants' untrained limbs were used to calculate the Hedges g effect sizes and 95% CIs. DATA SYNTHESIS: Our search returned 6 studies that met the inclusion criteria. The articles' risk of bias ranged from high to low (11-19). In 4 of 5 studies that examined unilateral balance training, the authors reported a cross-education effect. In the lone study that examined resistance training at the ankle joint, a cross-education effect was also present. Several cross-education effects were associated with large effect sizes. This systematic review was limited by a small number of studies that varied in methods and quality. CONCLUSIONS: Our results suggest that unilateral therapeutic exercise can improve balance performance of the untrained limb of individuals with CAI. More work is needed to determine which training protocols are most effective for generating a cross-education effect.

Survey of Korean pediatrician's perceptions of barriers to and improvements in breastfeeding.

BACKGROUND: Although the benefits of breastfeeding are broadly acknowledged with the efforts of the government and several medical societies, the rate of exclusive breastfeeding through 6 months is lower in Korea than in developed countries. PURPOSE: This study aimed to investigate pediatricians' perceptions of breastfeeding barriers and the current breastfeeding counseling environment and propose government policies to encourage breastfeeding in Korea. METHODS: Fourteen survey questions were developed during meetings of Korean Society of Breastfeeding Medicine experts. The Korean Pediatric Society emailed a structured questionnaire to domestic pediatricians registered as official members of the Korean Pediatric Society on May 4, 2021, and June 3, 2021. This study examined the survey responses received from 168 pediatricians. RESULTS: The 168 respondents included 62 professors, 53 paid doctors, and 53 private physicians. Breastfeeding was recommended by 146 Korean pediatricians (86.9%). However, only 99 responders (59%) currently provide breastfeeding counseling in hospitals. Most respondents stated providing less than 15 minutes of breastfeeding counseling time in the clinic. Moreover, 89.88% of the respondents responded that they would participate in breastfeeding counseling education if an appropriate breastfeeding counseling program was newly established. CONCLUSION: This study showed that, although Korean pediatricians had a positive attitude toward breastfeeding, limited counseling was provided for parents. Along with policy support to improve the medical environment through the establishment of an appropriate breastfeeding counseling program, high-quality counseling and an increased breastfeeding rate are expected.

Single-dose prophylactic ibuprofen therapy for patent ductus arteriosus in preterm infants.

This study aimed to evaluate the short-term morbidities and efficacy of single-dose prophylactic intravenous ibuprofen for patent ductus arteriosus (PDA) on the first day of life in preterm infants. Data of 69 preterm infants with birth weight < 1250 g and gestational age < 30 weeks admitted to the neonatal intensive care unit were analyzed. Of these, 37 infants were assigned to the prophylactic treatment (PT) group and 32 were assigned to the nonprophylactic treatment (non-PT) group. Only the PT group administered intravenous ibuprofen (10 mg/kg) once within 6 hours after birth. Until postnatal day 7, ductal closure occurred in 11 (34.4%) infants in the non-PT group, and in 35 (94.6%) infants in the PT group, of which 30 (81.1%) infants had ductal closure on postnatal day 1. There were 2 (5.4%) infants in the PT group and 9 (28.1%) in the non-PT group who needed ibuprofen treatment due to moderate-to-large PDA after postnatal day 7. Preterm infants in the PT group were less likely to develop an intraventricular hemorrhage (≥grade 2) (adjusted odds ratio 0.007, 95% confidence interval 0.01-0.45), had a shorter duration of invasive ventilatory support and central venous catheter, and earlier postnatal age to achieve feeding of 50 and 100 mL/kg/day compared with those in the non-PT group. Single-dose prophylactic intravenous ibuprofen on the first day of life decreased the occurrence of a persistent PDA and intraventricular hemorrhage (≥grade 2), and reduced the duration of invasive ventilatory support, central venous catheter use, and hospital stay.

Survey on the Status of Breastfeeding in Korean Medical Institution Workers.

BACKGROUND: Human breast milk is essential and provides irreplaceable nutrients for early humans. However, breastfeeding is not easy for various reasons in medical institution environments. Therefore, in order to improve the breastfeeding environment, we investigated the difficult reality of breastfeeding through questionnaire responses from medical institution workers. METHODS: A survey was conducted among 179 medical institution workers with experience in childbirth within the last five years. The survey results of 175 people were analyzed, with incoherent answers excluded. RESULTS: Of the 175 people surveyed, a total of 108 people (61.7%) worked during the day, and 33 people (18.9%) worked in three shifts. Among 133 mothers who stayed with their babies in the same nursing room, 111 (93.3%) kept breastfeeding for more than a month, but among those who stayed apart, only 10 (71.4%) continued breastfeeding for more than a month (P = 0.024). Ninety-five (88.0%) of daytime workers, 32 (94.1%) two-shift workers, and 33 (100%) three-shift workers continued breastfeeding for more than a month (P = 0.026). Workers in general hospitals tended to breastfeed for significantly longer than those that worked in tertiary hospitals (P = 0.003). A difference was also noted between occupation categories (P = 0.019), but a more significant difference was found in the comparison between nurses and doctors (P = 0.012). Longer breastfeeding periods were noted when mothers worked three shifts (P = 0.037). Depending on the period planned for breastfeeding prior to childbirth, the actual breastfeeding maintenance period after birth showed a significant difference (P = 0.002). Of 112 mothers who responded to the question regarding difficulties in breastfeeding after returning to work, 87 (77.7%) mentioned a lack of time caused by being busy at work, 82 (73.2%) mentioned the need for places and appropriate circumstances. CONCLUSION: In medical institutions, it is recommended that environmental improvements in medical institutions, the implementation of supporting policies, and the provision of specialized education on breastfeeding are necessary to promote breastfeeding.

Antenatal Betamethasone Induces Increased Surfactant Proteins and Decreased Foxm1 Expressions in Fetal Rabbit Pups.

Introduction: Antenatal steroid improves respiratory distress syndrome in preterm infants. The molecular mechanism of the process is not well established. The aim of this study is to investigate the possible association between antenatal steroid and fetal Forkhead box M1(Foxm1) expression. Materials and methods: An animal study using mated pregnant New Zealand white rabbits and their fetuses was designed. Fourteen mother rabbits were assigned to four groups to undergo a cesarean section. In groups 1, 2, and 3, preterm pups were harvested on day 27 of gestation. In group 4, term pups were harvested on day 31. Antenatal maternal intramuscular injection was performed in groups 2 (normal saline) and 3 (betamethasone). Using qRT-PCR and Western blot, mRNA transcription and protein expression of surfactant protein (SP) A, B, C, and Foxm1 were compared between the pups of those four groups. Results: Sixty two fetal rabbits were harvested. One-way ANOVA test showed higher mRNA transcription of SPs in groups 3 and 4 than groups 1 and 2. Significantly lower Foxm1 mRNA transcription and protein expression were observed in group 3 or 4 compared with group 1 or 2. Conclusion: Decreased Foxm1 expression was associated in an antenatal betamethasone animal model.

Comparison of Biomechanical Factors Before and After UCL Surgery in Baseball Athletes: A Systematic Review With Meta-analysis.

BACKGROUND: Ulnar collateral ligament (UCL) reconstruction (UCLR) and repair (UCLr) are the gold standards in the treatment of UCL injuries. Although return-to-play timelines after UCLR have been established, pitching biomechanical variables are speculated to change after surgical intervention. PURPOSE/HYPOTHESIS: To synthesize the literature and investigate changes in pitching biomechanics in baseball pitchers after UCLR or UCLr. We hypothesized that differences in pitching biomechanics would be observed for both intra- and interpatient comparisons. STUDY DESIGN: Systematic review; Level of evidence, 3. METHODS: We searched 4 electronic databases (PubMed, Web of Science, SCOPUS, and Sports Medicine & Education Index) from inception to February 2020. Data extracted included author and year of publication, study design, sample size, study population, and primary outcome variables. Meta-analysis was performed to produce random pooled effect sizes (▵). RESULTS: We identified 1010 original articles for inclusion. A total of 5 studies were included in the systematic review; of these, 3 studies were included in the meta-analysis. No differences were found in shoulder range of motion (ROM) between post-UCLR and control pitchers (dominant arm external rotation ▵, 0.13°; 95% CI, -0.15° to 4.02°; P = .36); dominant arm internal rotation ▵, -0.20°; 95% CI, -0.74° to 0.35°; P = .48). Mean fastball velocity as well as pitches thrown decreased after UCLR in professional pitchers. Significant differences in elbow extension, elbow extension velocity, and shoulder internal rotation velocity were found among amateur pitchers. CONCLUSION: The results of this systematic review and meta-analysis show that limited differences exist in pitchers before and after UCLR as well as in post-UCLR pitchers and healthy, age-matched controls. UCLR may influence throwing velocity, but it had no effect on either the throwing biomechanics or theROM of baseball pitchers. Although trends appear to be forming, further evidence is needed to understand the effect of UCLR on throwing biomechanics.

The reliability and validity of a digital version of the Cumberland Ankle Instability Tool.

PURPOSE: The Cumberland Ankle Instability Tool is a common patient reported outcome used to assess those with Chronic Ankle Instability. However, paper versions of the Cumberland Ankle Instability Tool have only been assessed for reliability purposes. The purpose of this study was to assess the agreement and reliability of a digital version of the Cumberland Ankle Instability Tool-Digital. MATERIALS AND METHODS: Sixty-eight participants with a history of ankle sprain(s) were recruited to participate in this study. Participants completed a paper version of the Cumberland Ankle Instability Tool and a digital version then returned one week later and completed them again. Intraclass correlation coefficients (ICC) and Kappa coefficients were used to determine the agreement between the paper and digital versions as well as test-retest reliability between the two time periods. RESULTS: The digital version showed excellent reliability (ICC = 0.93, 95% CI: 0.89-0.96) with the paper version. The test-retest reliability between testing sessions was considered good (ICC = 0.86, 95% CI: 0.77-0.92). A majority of individual items on the digital version demonstrated substantial agreement (κ = 0.60-0.81) with the paper version. CONCLUSIONS: A digital version of the Cumberland Ankle Instability Tool demonstrated good to excellent psychometric properties. Clinicians who utilize a digital version as part of an electronic medical record system can utilize them confidently to accurately assess patients with Chronic Ankle Instability. Future studies may want to consider assessing a digital version with expanded clinical and research populations.Implications for rehabilitationThe digital version of the Cumberland Ankle Instability Tool demonstrated adequate psychometric properties.The digital version of the Cumberland Ankle Instability Tool can be considered a reliable instrument for the assessment of Chronic Ankle Instability.A digital version of the Cumberland Ankle Instability Tool can provide automated scoring and quick administration for clinicians in a rehabilitation setting.

Congenital Anomalies in Very-Low-Birth-Weight Infants: A Nationwide Cohort Study.

BACKGROUND: Management of newborn infants with congenital anomalies is challenging and requires a multidisciplinary approach. The prevalence of congenital anomalies in very-low-birth-weight infants (VLBWIs; birth weight <1,500 g) has been rarely reported. OBJECTIVES: The aim of this study was to investigate the epidemiology of congenital anomalies in VLBWIs and the association with early mortality and major morbidities. STUDY DESIGN: A prospective cohort study was performed using data collected from 70 centers registered in the Korean Neonatal Network. Data from the VLBWIs with major congenital anomalies (n = 289) and the controls (n = 867), selected by 1:3 frequency matching for gestational age, were compared. RESULTS: The overall prevalence of major congenital anomalies in VLBWIs was 34.9 per 1,000 live births (289/8,156). The top 2 ranked subgroups of congenital anomalies were the digestive system (31.7%) and congenital heart defects (27.7%), followed by chromosomal anomalies, genitourinary tract defect, central nervous system, other anomalies, undefined, and respiratory system. The group with congenital anomalies had a higher mortality (40.7%) than the control group (11.1%). Each subgroup of congenital anomalies, except for chromosomal anomalies, increased the risk of mortality, with the highest odds ratio associated with "other" anomalies, which includes hydrops fetalis and congenital diaphragmatic hernia. In the multivariate analysis, congenital anomaly was a risk factor for mortality, bronchopulmonary dysplasia, and severe-grade intraventricular hemorrhage. VLBWIs with congenital anomaly demonstrated impaired in-hospital growth as compared with the control group. CONCLUSION: Congenital anomaly increased the risk of in-hospital mortality and was associated with short-term neonatal morbidities in the VLBWIs.

Does the Method of Administration Affect Reliability of the Foot and Ankle Ability Measure?

BACKGROUND: Region-specific patient-reported outcomes (PROs) are commonly used in rehabilitation medicine. Digital versions of PROs may be implemented into electronic medical records and are also commonly used in research, but the validity of this method of administration (MOA) must be established. PURPOSE: To determine the agreement between and compare the test-retest reliability of a paper version (FAAM-P) and digital version (FAAM-D) of the Foot and Ankle Ability Measure (FAAM). STUDY DESIGN: Randomized, nonblinded, crossover observational study. METHODS: A total of 90 adults were randomized to complete the FAAM-P or FAAM-D first, and then completed the second MOA (first day [D1]). The FAAM-D was a digital adaptation of both FAAM-P subscales on Qualtrics. Identical test procedures were completed 1 week later (D2). Data were removed if a participant scored 100% on both MOA, reported injury between D1 and D2, or did not complete both MOA. Agreement was assessed on 46 participants between the 2 MOA using intraclass correlation coefficients (ICC) at D1. There was good-to-excellent test-retest reliability for the FAAM activities of daily living. RESULTS: The authors observed good agreement between the FAAM-P and FAAM-D for the activities of daily living (ICC = .88) and sport scales (ICC = .87). Test-retest reliability was good-to-excellent for the FAAM activities of daily living (FAAM-P: ICC = .87; FAAM-D: ICC = .89) and sport (FAAM-P: ICC = .71; FAAM-D: ICC = .91). CONCLUSIONS: The MOA does not appear to affect the responses on the FAAM; however, the authors observed slightly higher reliability on the FAAM-D. The FAAM-D is sufficient to be used for generating practice-based evidence in rehabilitation medicine.

Maternal Exposure to Particulate Matter during Pregnancy and Adverse Birth Outcomes in the Republic of Korea.

Air pollution has become a global concern due to its association with numerous health effects. We aimed to assess associations between birth outcomes in Korea, such as preterm births and birth weight in term infants, and particulate matter < 10 µm (PM10). Records from 1,742,183 single births in 2010⁻2013 were evaluated. Mean PM10 concentrations during pregnancy were calculated and matched to birth data by registered regions. We analyzed the frequency of birth outcomes between groups using WHO criteria for PM10 concentrations with effect sizes estimated using multivariate logistic regression. Women exposed to PM10 > 70 µg/m³ during pregnancy had a higher rate of preterm births than women exposed to PM10 ≤ 70 µg/m³ (7.4% vs. 4.7%, P < 0.001; adjusted odds ratio (aOR) 1.570; 95% confidence interval (CI): 1.487⁻1.656). The rate of low birth weight in term infants increased when women were exposed to PM10 > 70 µg/m³ (1.9% vs. 1.7%, P = 0.278), but this difference was not statistically significant (aOR 1.060, 95% CI: 0.953⁻1.178). In conclusion, PM10 exposure > 70 µg/m³ was associated with preterm births. Further studies are needed to explore the pathophysiologic mechanisms and guide policy development to prevent future adverse effects on birth outcomes.

Trends in Birth Weight and the Incidence of Low Birth Weight and Advanced Maternal Age in Korea between 1993 and 2016.

BACKGROUND: As the aging society progresses, the average age of mothers is also increasing. Advanced maternal age has been known to be associated with perinatal outcomes, as well as birth weight (BW). In this study, we aimed to investigate the perinatal factors associated with low birth weight infants (LBWIs) using birth statistics of the Korean population. METHODS: Birth statistics between 1993 and 2016 from the Korean Statistical Information Service were reviewed. We investigated 12,856,614 data points, which included the number of births, BWs, percentage of preterm births and LBWIs, multiple pregnancies, and maternal age. RESULTS: The proportion of LBWIs delivered by mothers of advanced maternal age has gradually increased since 1993. In addition, the proportion of older mothers (≥ 35 years old) giving birth to LBWIs has increased over the years. Average BW has a negative correlation with the ratio of preterm births, LBW, multiple births, and advanced maternal age. The mean BW also has a negative correlation with maternal age. CONCLUSION: This study shows that the average BW continues to decline, and the incidence of LBWIs is increasing in Korea since 1993. This study also revealed that several perinatal factors, including percentage of preterm births, LBWIs, multiple births, and maternal age influence the mean BW. Although this study did not investigate the effects of decreasing mean BW on perinatal health, future research is worth discussing.

Association of Surfactant Protein with Expression of Hoxa5 and Hoxb5 in Rabbit Fetal Lung.

Hox genes regulate organ formation and identity of the embryo, and expressed in specific temporo-spatial patterns in the developing embryo. We compared the expression levels of the Hoxa5, Hoxb5, surfactant protein (SP)-A, and SP-B genes in immature and mature rabbit fetal lung tissues, and to uncover roles for Hoxa5, Hoxb5, SP-A, and SP-B. Cesarean sections were performed after rabbits were divided into two groups of 30-31 days of gestation (term group, n = 24) and 26-27 days of gestation (preterm group, n = 24). mRNA levels of Hoxa5, Hoxb5, SP-A, and SP-B were compared by quantitative reverse transcriptase polymerase chain reaction, and protein expression of Hoxa5 and Hoxb5 was compared by western blot analysis. Fetal lung tissue histology was observed by hematoxylin and eosin (H&E) staining. The relative expression ratios of SP-A and SP-B mRNA in the term to preterm groups were 2.45:1 and 2.94:1, respectively. Hoxb5 mRNA and protein levels decreased in the term group, with a relative expression ratio of 0.48:1 and 0.50:1, however, Hoxa5 mRNA and protein levels increased in the term group with a relative expression ration of 2.99:1 and 2.33:1, respectively, for the term to preterm groups. Moreover, a significant positive correlation was found between the expression of Hoxa5 and SP-A, SP-B in the term group. Hoxa5 gene may be essential for the expression of SP-A and SP-B in term rabbits. The Hoxb5 gene may be an important factor for lung maturation in preterm rabbits.