Analysis of BPD in Premature Infants With Typical Imaging Changes

Study Overview
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Brief Summary
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Bronchopulmonary dysplasia (BPD) is a common chronic respiratory disease in preterm infants. The increase in the survival rate of premature babies following the improvement of perinatal treatment and care has caused an increase in the incidence of BPD in recent years, which has seriously affected the quality of life of preterm infants. According to the consensus reached at the workshop sponsored by the National Institute of Child Health and Human Development (NICHD) in 2001, BPD was clinically defined based on oxygen dependency in preterm infants. However, the refined NICHD definition of BPD in 2018 emphasizes imaging findings to support a diagnosis of lung parenchyma disease. Fibrotic opacities and cystic changes on chest imaging (chest X-ray [CXR] or computed tomography [CT] scan) were considered typical findings in BPD patients. In patients with severe BPD, the presence of bubbles/cystic appearance on CXR after 28 days of life was reported to be an important factor, and typical imaging findings can predict a poor pulmonary outcome in BPD patients. BPD is associated with poor outcomes. Although many studies have been conducted on BPD, there are limited reports specifically evaluating the association of typical imaging findings with clinical characteristics and later outcomes in patients with BPD. We hypothesized that BPD with typical imaging findings was likely to be a particular subgroup of this entity, with a unique etiology, clinical characteristics and prognosis. Therefore, this retrospective study aimed to compare clinical characteristics, short-term outcomes and follow-up data until 2 years of age in preterm infants with or without typical imaging findings of BPD on CXR or CT scan during the entire hospital stay. A propensity score analysis was used to reduce bias between the two groups, and multivariate logistic regression analysis was performed to identify factors related to mortality in preterm infants with BPD.

Official Title
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Clinical Characteristics and Outcome Analysis of Bronchopulmonary Dysplasia in Premature Infants With Typical Imaging Changes

Conditions
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Bronchopulmonary Dysplasia

Intervention / Treatment
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* Other: no intervention


Participation Criteria
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Eligibility Criteria
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inclusion criteria: (1) BPD diagnosis according to the 2001 NICHD consensus; (2) chest imaging examination (CXR or CT) in the first week after birth; and (3) hospitalization within the first 7 days after birth. exclusion criteria: (1) major congenital malformations or laboratory-confirmed chromosomal abnormalities; (2) inadequate clinical data or missing chest imaging data; or (3) loss to follow-up.

Ages Eligible for Study
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Maximum Age: 2 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| group with typical imaging changes<br>the BPD infants with typical chest imaging findings include fibrotic opacities and cysts on CXR or CT scans during the entire hospital stay. | Other: no intervention<br>* no intervention, only observation<br>|
| group without typical imaging changes<br>the infants meet the diagnosis criteria of BPD, but lack of typical chest imaging findings | Other: no intervention<br>* no intervention, only observation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mortality | the number of death/total number（%） | between 28 days after birth and 2 years of age | 
| Number of Participants According to the Severity of BPD | Mild BPD: Breathing room air Moderate BPD: Need* for < 30% oxygen Severe BPD: Need* for ≥ 30% oxygen and/or positive pressure | 36 wk PMA(infants with GA>32w) or>28 d but <56 d(infants with GA>32w) or discharge to home, whichever comes first | 
| Number of Participants Who Need HOT at Discharge | need of home oxygen therapy (HOT) at discharge | at discharge, an average of 2 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Duration of Hospital Stay | days between admission and first discharge | at discharge, an average of 2 months | 
| Routine Physical Assessment | the measure of infant's length and weight: Underweight/Stunting Stunting was defined as >2 standard deviations (SD) below the mean length for age, and underweight was defined as >2 SD below the mean weight for age. Weight and length were calculated with Chinese growth reference standards | 2 Years of Age | 
| Days of Oxygen Supplement | days during which the infants were given oxygen supplement | at discharge, an average of 46-56 days | 
| Wheezing Disorders | Wheezing disorders were defined as a physician diagnosis of wheezing exposure treated with anti-asthma drugs (bronchodilators and corticosteroids) | between discharge and follow-up, an average of 22 months | 
| Clinical Visits and Rehospitalizations | clinical visits and rehospitalizations for a respiratory reason | between discharge and follow-up until 2 years of age, an average of 22 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bronchopulmonary dysplasia, typical chest imaging findings, clinical characteristics, outcomes, preterm infants, propensity score