RESUMEN
Background: Bronchopulmonary dysplasia is a common pulmonary disease in newborns and is one of the main causes of death. The aim of this study was to build a new simple-to-use nomogram to screen high-risk populations. Methods: In this single-center retrospective study performed from January 2017 to December 2020, we reviewed data on very-low-birth-weight infants whose gestational ages were below 32 weeks. LASSO regression was used to select variables for the risk model. Then, we used multivariable logistic regression to build the prediction model incorporating these selected features. Discrimination was assessed by the C-index, and and calibration of the model was assessed by and calibration curve and the Hosmer-Lemeshow test. Results: The LASSO regression identified gestational age, duration of ventilation and serum NT-proBNP in the 1st week as significant predictors of BPD. The nomogram-illustrated model showed good discrimination and calibration. The C-index was 0.853 (95% CI: 0.851-0.854) in the training set and 0.855 (95% CI: 0.77-0.94) in the validation set. The calibration curve and Hosmer-Lemeshow test results showed good calibration between the predictions of the nomogram and the actual observations. Conclusion: We demonstrated a simple-to-use nomogram for predicting BPD in the early stage. It may help clinicians recognize high-risk populations.
RESUMEN
OBJECTIVE: In the early life of preterm infants, the relationship between heart function and length of hospitalization is unclear. This study aims to examine the association between serum NT-proBNP level on the 7th day (NT-proBNP7) after birth and length of hospitalization among preterm infants. METHODS: A retrospective cohort study was conducted. Patients included 709 preterm infants born at 28-31 weeks' gestational age (GA) admitted to the NICU of the First Affiliated Hospital of Zhengzhou University between December 20, 2016, to April 31, 2021. Main outcome: Late discharge (postmenstrual age at discharge was in the fourth quartile (highest) among infants born at the same GA). Exposure factor: NT-proBNP7. RESULTS: We observed increased prevalence ratios for late discharge among the tertile of logarithm of NT-proBNP7 level (LnNT-proBNP7) which was positive. Compared with the lowest tertile, infants in the highest tertile of LnNT-proBNP7 had an 8.4-fold increased probability of late discharge, and the results were consistent for the subgroups. Next, a non-linear (S-shaped) relationship between LnNT-proBNP7 and late discharge was observed, whose turning points were 7.5 and 9. The effect sizes and the confidence intervals on the left of the first turning point, between two turning points and on the right of the second turning point, were 0.6 (95% CI, 0.2-1.6), 5.0 (95% CI, 2.4-10.6), and 1.1 (95% CI, 0.2-6.1), respectively. In addition, the prevalence of BPD, NEC, nosocomial infection, or any of them was highest in the group of LnNT-proBNP7 ≥ 9, lowest in the group of LnNT-proBNP7 < 7.5. CONCLUSION: Higher NT-proBNP7 levels were associated with longer hospitalization. The relationship between LnNT-proBNP7 and late discharge was S-shaped. LnNT-proBNP7 was positively related with late discharge when LnNT-proBNP7 was between 7.5 and 9.
RESUMEN
OBJECTIVE: To study the effect of dexamethasone on airway morphology and on the expression of angiopoietin-1 (Ang-1) and its tyrosine kinase receptor Tie-2 in the airway of asthmatic rats. METHODS: Forty-five Sprague-Dawley rats were randomly divided into control, asthmatic, and dexamethasone-treated asthmatic groups. Asthma was induced by repeated sensitization and challenge with ovalbumin in the latter two groups. The dexamethasone intervention group received an intraperitonea injection of dexamethasone (2 mg/kg) before asthma challenge. Immunohistochemistry was used to measure the expression of Ang-1 and Tie-2 in the airway. Airway thickness was estimated by a computerized digital image analyzer. RESULTS: Airway thickness in the asthmatic group (33.9333+/-8.3791 micro m2/micro m) increased significantly compared with that in the control group (21.1333+/-2.7740 micro m2/micro m) (P<0.01). The dexamethasone intervention group also showed increased thickness of the airway (27.4000 +/- 4.6105 micro m2/micro m) compared with the control group (P<0.01), but the airway thickness in the dexamethasone intervention group was significantly reduced compared with that in the untreated asthmatic group (P<0.01). The expression of Ang-1 (103.9487+/-8.2914 vs 76.0320+/-3.7728; P<0.01) and Tie-2 (99.2307+/-8.1913 vs 75.3153+/-3.7321; P<0.01) in the airway increased significantly in the asthmatic group compared to controls. The expression of Ang-1 and Tie-2 in the airway of the dexamethasone intervention group (90.6180+/-5.2339 and 86.6633+/-3.7321, respectively) was statistically higher than that in the control group (P<0.01) but statistically lower than that in the untreated asthmatic group (P<0.01). Ang-1 and Tie-2 expression in the airway was positively correlated with the thickness of airway (r(Ang)-1=0.719r(Tie)-2=0.746P<0.01). There was also a positive correlation between Ang-1 and Tie-2 expression (r=0.742P<0.01). CONCLUSIONS: The expression of Ang-1 and Tie-2 in the airway increased in asthmatic rats and was positively correlated with the thickness of the airway. Ang-1 and Tie-2 may participate in the process of airway remodeling in asthma. Dexamethasone can decrease the expression of Ang-1 and Tie-2 in the airway and relieve the changes of airway morphology.