Objective: To explore the risk factors of pulmonary hypertension (PH) in premature infants with bronchopulmonary dysplasia (BPD), and to establish a prediction model for early PH. Methods: This was a retrospective cohort study. Data of 777 BPD preterm infants with the gestational age of <32 weeks were collected from 7 collaborative units of the Su Xinyun Neonatal Perinatal Collaboration Network platform in Jiangsu Province from January 2019 to December 2022. The subjects were randomly divided into a training cohort and a validation cohort at a ratio of 8∶2 by computer, and non-parametric test or χ² test was used to examine the differences between the two retrospective cohorts. Univariate Logistic regression and multivariate logistic regression analyses were used in the training cohort to screen the risk factors affecting the PH associated with BPD. A nomogram model was constructed based on the severity of BPD and its risk factors,which was internally validated by the Bootstrap method. Finally, the differential, calibration and clinical applicability of the prediction model were evaluated using the training and verification queues. Results: A total of 130 among the 777 preterm infants with BPD had PH, with an incidence of 16.7%, and the gestational age was 28.7 (27.7, 30.0) weeks, including 454 males (58.4%) and 323 females (41.6%). There were 622 preterm infants in the training cohort, including 105 preterm infants in the PH group. A total of 155 patients were enrolled in the verification cohort, including 25 patients in the PH group. Multivariate Logistic regression analysis revealed that low 5 min Apgar score (OR=0.87, 95%CI 0.76-0.99), cesarean section (OR=1.97, 95%CI 1.13-3.43), small for gestational age (OR=9.30, 95%CI 4.30-20.13), hemodynamically significant patent ductus arteriosus (hsPDA) (OR=4.49, 95%CI 2.58-7.80), late-onset sepsis (LOS) (OR=3.52, 95%CI 1.94-6.38), and ventilator-associated pneumonia (VAP) (OR=8.67, 95%CI 3.98-18.91) were all independent risk factors for PH (all P<0.05). The independent risk factors and the severity of BPD were combined to construct a nomogram map model. The area under the receiver operating characteristic (ROC) curve of the nomogram model in the training cohort and the validation cohort were 0.83 (95%CI 0.79-0.88) and 0.87 (95%CI 0.79-0.95), respectively, and the calibration curve was close to the ideal diagonal. Conclusions: Risk of PH with BPD increases in preterm infants with low 5 minute Apgar score, cesarean section, small for gestational age, hamodynamically significant patent ductus arteriosus, late-onset sepsis, and ventilator-associated pneumonia. This nomogram model serves as a useful tool for predicting the risk of PH with BPD in premature infants, which may facilitate individualized early intervention.
Infant ; Male ; Infant, Newborn ; Humans ; Pregnancy ; Female ; Bronchopulmonary Dysplasia/epidemiology* ; Infant, Premature ; Hypertension, Pulmonary/epidemiology* ; Retrospective Studies ; Nomograms ; Ductus Arteriosus, Patent/epidemiology* ; Pneumonia, Ventilator-Associated/complications* ; Cesarean Section/adverse effects* ; Gestational Age ; Risk Factors ; Sepsis

OBJECTIVES: To investigate the risk factors for moderate/severe bronchopulmonary dysplasia (BPD) in preterm infants with a gestational age of <32 weeks. METHODS: A retrospective analysis was performed on the medical data of preterm infants with a gestational age of <32 weeks and a length of hospital stay of ≥28 days who were admitted to the neonatal intensive care unit (NICU) of 17 institutions of Jiangsu Neonatal Perinatal Cooperation Network from January 1, 2019 to December 31, 2020 and were diagnosed with BPD. The preterm infants were grouped according to gestational age and severity of BPD. A multivariate logistic regression analysis was used to investigate the risk factors for moderate/severe BPD in various gestational age groups. RESULTS: During the two-year period, a total of 2 603 preterm infants with a gestational age of <32 weeks were admitted to the NICU of the 17 institutions, among whom 961 were diagnosed with BPD, and the incidence rates of BPD and moderate/severe BPD were 36.92% (961/2 603) and 8.64% (225/2 603), respectively. The incidence rate of moderate/severe BPD was 56.5% (26/46) in preterm infants with a gestational age of 24⁺⁰-25⁺⁶ weeks, 31.0% (66/213) in those with a gestational age of 26⁺⁰-27⁺⁶ weeks, 16.9% (75/445) in those with a gestational age of 28⁺⁰-29⁺⁶ weeks, and 22.6% (58/257) in those with a gestational age of 30⁺⁰-31⁺⁶ weeks. The multivariate logistic regression analysis showed that there were different risk factors for moderate/severe BPD in preterm infants with different gestational ages: patent ductus arteriosus requiring treatment as risk factors in preterm infants with a gestational age of 24⁺⁰-25⁺⁶ weeks; premature rupture of membranes ≥18 hours, positive pressure ventilation for resuscitation, clinical sepsis, and duration of mechanical ventilation ≥14 days as risk factors in preterm infants with a gestational age of 26⁺⁰-27⁺⁶ weeks; duration of mechanical ventilation ≥14 days, neonatal pneumonia, and patent ductus arteriosus requiring treatment as risk factors in preterm infants with a gestational age of 28⁺⁰-29⁺⁶ weeks; positive pressure ventilation for resuscitation, neonatal pneumonia, and anemia of prematurity as risk factors in preterm infants with a gestational age of 30⁺⁰-31⁺⁶ weeks (P<0.05). CONCLUSIONS The development of moderate/severe BPD is multifactorial in preterm infants with a gestational age of <32 weeks, and there are different risk factors in different gestational age groups. Targeted preventive measures for preterm infants of different gestational ages may be useful to reduce the severity of BPD.
Infant ; Pregnancy ; Female ; Infant, Newborn ; Humans ; Bronchopulmonary Dysplasia/etiology* ; Gestational Age ; Infant, Premature ; Ductus Arteriosus, Patent ; Retrospective Studies ; Risk Factors ; Pneumonia/complications*

To analyze clinical characteristics and risk factors of very low birth weight and extremely low birth weight infants with bronchopulmonary dysplasia (BPD). A retrospective epidemiological study was performed in 768 neonates (376 males) with birth weights<1 500 g and gestational age ≤ 34 weeks who survived ≥28 days. Clinical data were obtained from the multi-center clinical database of neonatal intensive care units (NICU) in 19 hospitals of Jiangsu Province between January 1, 2017 and December 31, 2017. These infants were divided into non-BPD group and BPD group according to BPD diagnositic criteria. Clinical features and potential risk factors were compared between groups with Chi-square test or nonparametric test. Risk factors for BPD were analyzed with Logistic regression analysis. Among the total of 768 eligible neonates, 577 without BPD, 191 with BPD (24.9%). Mild, moderate and severe BPD accounted for 73.3% (140/191), 23.6% (45/191) and 3.1% (6/191) of all BPD cases respectively. There were significant differences in the average gestational age (29 (28, 30) 30 (29, 31) weeks) or the average birth weight (1 170 (990, 1 300) 1 300 (1 160, 1 400) g) between BPD group and non-BPD group (-9.959,-7.202, both 0.000). The incidences of BPD in the infants with gestational age of<28 weeks, 28-31 weeks and 32-34 weeks were 51.7% (46/89), 24.8% (139/561), 5.1% (6/118) respectively. The incidences of BPD in infants with birth weigh1 000 g, 1 000- 1 249 g and 1 250-1 500 g were 62.3% (48/77), 25.9% (70/270) and 17.3% (73/421) respectively. Proportion of male (55.5% (106/191) 46.8% (270/577)), rate and length of conventional mechanical ventilation (48.7% (93/191) 14.9% (86/577), 120 (72, 259) 80 (29, 144)h), initial inhaled oxygen concentration and maximum inhaled oxygen concentration (0.35 (0.30, 0.40) 0.30(0.25, 0.40), 0.40 (0.30, 0.50) 0.30 (0.30, 0.40)) and volume of red blood cell transfusion (53(30, 90) .38(28, 55) ml) were higher in BPD group than in non-BPD group (χ(2)=4.350, 91.640, -3.557, -2.848, -3.776, -4.677, all 0.05). Rate of continuous positive airway pressure (12.6%(24/191) 19.4%(112/577)) during neonatal resuscitation in delivery room was lower in BPD group than that in non-BPD group (χ(2)=4.614, 0.032). The incidences of complications in BPD group including severe asphyxia, neonatal respiratory distress syndrome (NRDS), persistent pulmonary hypertension in newborns (PPHN), patent ductus arteriosus, anemia of prematurity, early onset sepsis, clinical sepsis and ventilator associated pneumonia were higher than that in non-BPD group (15.2%(29/191) 4.5% (26/577), 91.1% (174/191) 56.7% (327/577), 2.6% (5/191) 0.2% (1/577), 43.5% (83/191) 34.2% (197/577), 88.0% (168/191) 58.8% (339/577), 15.7% (30/191) 9.9% (57/577), 42.9% (82/191) 18.6% (107/577), 14.1% (27/191) 2.3% (13/577); χ(2)=24.605, 74.993, 9.167, 5.373, 61.866, 4.557, 43.149, 34.315, all 0.05). Multivariate logistic regression analysis showed that NRDS (4.651, 95: 1.860-11.625), clinical sepsis (1.989, 95: 1.067-3.708), ventilator associated pneumonia (3.155, 95: 1.060-9.388), conventional mechanical ventilation (2.298, 95: 1.152-4.586), and volume of red blood cell transfusion (1.013, 95: 1.002-1.024) were risk factors of BPD. BPD is more common in very low birth weight infants of male with gestational age less than 32 weeks. Using CPAP in the delivery room, active treatment of NRDS, preventing nosocomial infection, and reducing invasive ventilation and red blood cell transfusion may decrease the incidence of BPD.
Birth Weight ; Bronchopulmonary Dysplasia ; complications ; epidemiology ; pathology ; Gestational Age ; Humans ; Infant ; Infant, Extremely Low Birth Weight ; Infant, Newborn ; Infant, Very Low Birth Weight ; Male ; Respiratory Distress Syndrome, Newborn ; Retrospective Studies ; Risk Factors

OBJECTIVETo study the effect of rhubarb on neonatal rats with bronchopulmonary dysplasia (BPD) induced by hyperoxia.

METHODSA total of 64 rats (postnatal day 4) were randomly divided into four groups: air control, rhubarb control, hyperoxia model, and hyperoxia+rhubarb (n=16 each). The rats in the hyperoxia model and hyperoxia+rhubarb groups were exposed to hyperoxia (60% O2) to establish a BPD model. The rats in the rhubarb control and hyperoxia+rhubarb groups were given rhubarb extract suspension (600 mg/kg) by gavage daily. The pathological changes of lung tissue were evaluated by hematoxylin-eosin staining on postnatal days 14 and 21. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were measured by spectrophotometry. The mRNA and protein expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) were determined by RT-PCR and Western blot respectively.

RESULTSThe hyperoxia model group showed reduced alveolar number, increased alveolar volume, and simplified alveolar structure, which worsened over the time of exposure to hyperoxia. These pathological changes were significantly reduced in the hyperoxia+rhubarb group. On postnatal days 14 and 21, compared with the air control and rhubarb control groups, the hyperoxia model group had significantly reduced radical alveolar count (RAC), significantly reduced activity of SOD in the lung tissue, and significantly increased content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05). Compared with the hyperoxia model group, the hyperoxia+rhubarb group had significantly increased RAC, significantly increased activity of SOD in the lung tissue, and significantly reduced content of MDA and mRNA and protein expression levels of TNF-α and IL-6 (P<0.05).

CONCLUSIONSRhubarb may play a protective role in rats with BPD induced by hyperoxia through inhibiting inflammatory response and oxidative stress.

Animals ; Animals, Newborn ; Bronchopulmonary Dysplasia ; metabolism ; pathology ; prevention & control ; Disease Models, Animal ; Hyperoxia ; complications ; Lung ; metabolism ; pathology ; Plant Extracts ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Rheum ; Superoxide Dismutase ; metabolism ; Tumor Necrosis Factor-alpha ; genetics

OBJECTIVETo study the expression of SUMO-modified CCAAT enhancer binding protein α (C/EBPα) in preterm rat model of bronchopulmonary dysplasisa (BPD) induced by hyperoxia exposure and its role.

METHODSEighteen preterm rats were randomly divided into an air group and a hyperoxia group (n=9 each). The model of BPD was prepared in preterm rats exposed to hyperoxia. The rats from the two groups were sacrificed on postnatal days 4, 7 and 14 respectively (3 rats at each time) and lung tissues were harvested. Periodic acid-Schiff (PAS) staining was used to observe the differentiation of rat lung tissues. Ki67 expression was detected by immunohistochemistry. Western blot was used to measure the protein expression of small ubiquitin-related modifier-1(SUMO1) and C/EBPα. A co-immunoprecipitation assay was performed to measure the protein expression of SUMO-modified C/EBPα.

RESULTSCompared with the air group, the hyperoxia group showed a decreased glycogen content in the lung tissue on postnatal day 4, and an increased content on postnatal days 7 and 14. Over the time of hyperoxia exposure, the hyperoxia group showed an increased expression of Ki67 in the lung tissue compared with the air group at all time points. Compared with the air group, the protein expression of C/EBPα increased on postnatal day 4 and decreased on postnatal days 7 and 14 in the hyperoxia group (P<0.05). The hyperoxia group had significantly upregulated expression of SUMO1 and SUMO-modified C/EBPα compared with the air group at all time points (P<0.05). In the hyperoxia group, the protein expression of SUMO-modified C/EBPα was positively correlated with the glycogen content (r=0.529, P<0.05) and the expression of Ki67 (r=0.671, P<0.05).

CONCLUSIONSHyperoxia may induce over-proliferation and differentiation disorders of alveolar epithelial cells in preterm rat model of BPD, possibly through an increased expression of SUMO-modified C/EBP&alpha.

Animals ; Animals, Newborn ; Bronchopulmonary Dysplasia ; etiology ; metabolism ; pathology ; CCAAT-Enhancer-Binding Protein-alpha ; metabolism ; Cell Proliferation ; Disease Models, Animal ; Hyperoxia ; complications ; pathology ; Ki-67 Antigen ; analysis ; Pulmonary Alveoli ; pathology ; Rats ; Rats, Sprague-Dawley ; Sumoylation

OBJECTIVETo assess the association between serum 25-hydroxyvitamin D [25(OH)D] levels at birth and bronchopulmonary dysplasia (BPD) in preterm infants.

METHODSThis study recruited preterm infants with gestational age of below 34 weeks who were born between January 2014 and December 2016. These preterm infants were classified into two groups: BPD and control. The association between serum 25(OH)D levels at birth and BPD was analyzed.

RESULTSSerum 25(OH)D levels in the BPD group was significantly lower than those in the control group [(37±17 nmol/L vs 47±20 nmol/L; P<0.05), and the rate of vitamin D deficiency was significantly higher than those in the control group (90.2% vs 74.0%; P<0.05). The level of serum 25(OH)D was negatively correlated with the incidence of BPD (r=-0.201, P=0.001).

CONCLUSIONSVitamin D deficiency at birth may be associated with BPD in preterm infants, but need to be further studied by multivariate analysis.

Bronchopulmonary Dysplasia ; blood ; etiology ; Female ; Humans ; Infant, Newborn ; Infant, Premature ; blood ; Male ; Vitamin D ; analogs & derivatives ; blood ; Vitamin D Deficiency ; complications

With the development of treatment, the survival rate of premature infants has significantly increased, especially extremely premature infants and very low birth weight infants. This has led to an increase in incidence of bronchopulmonary dysplasia (BPD) year by year. BPD has been one of the most common respiratory system diseases in premature infants, especially the small premature infants. Arrested alveolar development is an important cause of BPD. Therefore, the mechanism of arrested alveolar development and the intervention measures for promoting alveolar development are the focuses of research on BPD. Selecting the appropriate animal model of BPD is the key to obtaining meaningful results in the basic research on BPD. Based on above, several common methods for establishing an animal model of BPD and the corresponding changes in pathophysiology are summarized and evaluated in order to provide a reference for selecting the appropriate animal model in studies on the pathogenesis, pathophysiology, and prevention and control strategies of BPD.
Animals ; Bronchopulmonary Dysplasia ; etiology ; Disease Models, Animal ; Humans ; Hyperoxia ; complications ; Respiration, Artificial ; adverse effects

Conflicting results on the influences of histologic chorioamnionitis (HC) on neonatal morbidities might be partly originated from using different definition of HC. The aim of this study was to determine the relationship between HC and neonatal morbidities using definition of HC that reflects the site and extent of inflammation. This was a retrospective cohort study of 261 very low birth weight (VLBW) infants admitted at a tertiary academic center. Based on the site of inflammation, HC was categorized: any HC; amnionitis; funisitis; amnionitis+funisitis. The extent of inflammation in each site was reflected by sub-defining high grade (HG). The incidences of morbidities in infants with and without HC were compared. The bronchopulmonary dysplasia (BPD) rate was significantly higher in infants with amnionitis and the severe retinopathy of prematurity (ROP) rate was significantly higher in infants with any HC and funisitis. After adjustment for both gestational age and birth weight, the respiratory distress syndrome (RDS) rate was significantly lower in infants with all categories of HC except for HG amnionitis and HG funisitis, which are not associated with lower RDS rate. HG amnionitis was significantly associated with increased BPD rate but the association of HC with severe ROP disappeared. In conclusion, HC is significantly associated with decreased RDS and HG amnionitis with increased BPD while lacking association with other neonatal morbidities in VLBW infants. The association with HC and neonatal morbidities differs by the site and extent of chorioamnionitis.
Adult ; Birth Weight ; Bronchopulmonary Dysplasia/complications/*epidemiology ; Chorioamnionitis/classification/*epidemiology/pathology ; Cohort Studies ; Female ; Gestational Age ; Humans ; Infant, Newborn ; *Infant, Very Low Birth Weight ; Neutrophil Infiltration/immunology ; Placenta/pathology ; Pre-Eclampsia/*epidemiology/pathology ; Pregnancy ; Respiratory Distress Syndrome, Newborn/complications/*epidemiology ; Retinopathy of Prematurity/complications/*epidemiology ; Retrospective Studies ; Tertiary Care Centers

PURPOSE: Extremely low birth weight infants (ELBWIs) have a high risk of acquiring cytomegalovirus (CMV) infection via breast milk and consequently developing serious symptoms. We evaluated whether freeze-thawing or pasteurization could prevent postnatal CMV infection transmitted through breast milk in ELBWIs. MATERIALS AND METHODS: Medical records of 385 ELBWIs with whole milk feeding, and freeze-thawed or pasteurized breast milk feeding were reviewed retrospectively. Postnatally acquired CMV infection was defined as an initial negative and a subsequent positive on follow-up urine CMV DNA polymerase chain reaction screening tests. The incidence, clinical characteristics, symptoms, sequelae, and long-term outcome at corrected age [(CA): 2 years of CMV infection] were analyzed. RESULTS: While no infant developed CMV infection with whole milk (0/22) or pasteurized breast milk (0/62) feeding, postnatal CMV infection was diagnosed in 8% (27/301) of ELBWIs who were fed freeze-thawed breast milk. Gestational age in the CMV group was significantly lower than the control group. In 82% (22/27) of cases, CMV infection was symptomatic and was associated with increased ventilator days and > or =moderate bronchopulmonary dysplasia (BPD). Neurodevelopmental outcome and growth status at CA 2 years were not different between the study groups. Lower gestational age and freeze-thawed breast milk feeding >60% of total oral intake during the first 8 postnatal weeks were independent risk factors for acquiring postnatal CMV infection. BPD (> or =moderate) was the only significant adverse outcome associated with this CMV infection. CONCLUSION: Pasteurization but not freeze-thawing of breast milk eradicated the postnatal acquisition of CMV infection through breast milk.
Adult ; Breast Feeding ; Bronchopulmonary Dysplasia ; Cytomegalovirus/*isolation & purification ; Cytomegalovirus Infections/epidemiology/prevention & control/*transmission ; Female ; Gestational Age ; Humans ; Incidence ; Infant ; *Infant, Extremely Low Birth Weight ; Infant, Newborn ; Infectious Disease Transmission, Vertical/*prevention & control ; Male ; Milk, Human/chemistry/*virology ; Polymerase Chain Reaction ; Pregnancy ; Pregnancy Complications, Infectious/diagnosis ; Retrospective Studies ; Risk Factors

The aim of this study was to observe the effects of prophylactic palivizumab on hospitalization secondary to respiratory syncytial virus (RSV) infection (RSVhospitalization) in former very low birth weight infants (VLBWI) with bronchopulmonary dysplasia (BPD). This study also sought to identify the risk factors of RSVhospitalizationin this particular infant population. A prospective observational study was conducted between September 2007 and April 2008 in seven Korean hospitals. Children with a history of very low birth weight, a diagnosis of BPD and who were <2 yr old at the onset of the RSV season were included in this study. Palivizumab injections were administered monthly for a maximum of five months during the RSV season. RSVhospitalization rates were reviewed, and RSVhospitalization rates between subgroups were categorized by gestational age, birth weight, and duration of ventilator care. A total of 90 subjects completed the follow-up interviews. The mean gestational age at birth was 26.1+/-1.7 weeks, and the mean birth weight was 889.4+/-222.2 g. The incidence of RSVhospitalization in the study population was 8.9% (8/90), and the mean hospital stay was 11.0+/-5.5 days, including one death. There were no statistically significant differences in the patients' demographic characteristics or risk factors for RSV hospitalization. When subgroup analyses were conducted, there were still no statistically significant differences. The administration of palivizumab prophylaxis during the entire RSV season is important in VLBWI with BPD, regardless of their gestational age and birth weight, or previous ventilator dependency.
Antibiotic Prophylaxis/*methods ; Antiviral Agents/*therapeutic use ; Birth Weight ; Bronchopulmonary Dysplasia/*complications ; Female ; Gestational Age ; Hospitalization/statistics & numerical data ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; *Infant, Very Low Birth Weight ; Length of Stay ; Male ; Palivizumab/*therapeutic use ; Prospective Studies ; Respiratory Syncytial Virus Infections/drug therapy/*epidemiology/prevention & control ; Respiratory Syncytial Viruses/drug effects ; Risk ; Risk Factors