(39) Nailfold Capillary Density Analysis to Help Predict the Development of BPD in Preterm Infants

Background: Bronchopulmonary dysplasia (BPD) is a major complication of prematurity with a lifelong health impact. It is characterized by alveolar simplification and microvascular remodeling. Although several BPD prediction models and biomarkers have been proposed, they have limited accuracy in early diagnosis and inconsistent performance across different patient populations. More robust biomarkers are needed to help guide the development of new preventative and therapeutic strategies. Nailfold capillaroscopy is a non-invasive technique which uses light microscopy to obtain real-time magnified images of the nailbed microvasculature. It has been commonly used in adults and children with rheumatologic disorders to predict relapses. However, microvascular density metrics have not yet been evaluated as a potential novel, non-invasive and early biomarker for BPD.

Objectives: To test the hypothesis that microvascular density metrics obtained through nailfold capillaroscopy in the first month of life can help predict the development of BPD in preterm infants born prior to 32 weeks of gestation.

Design/Methods: In an initial cohort of 37 infants born < 32 weeks gestation, images of the three middle fingers of each hand were obtained during the first 2 weeks of life. 23 infants (62% of the cohort) had paired images obtained 2 weeks later. Vessel length density of each acquired image was assessed using a previously validated machine learning-based segmentation approach that allows for blood vessel isolation and quantification. Results were correlated with the subsequent development of BPD, defined as the need for any supplemental respiratory support at 36 weeks corrected gestational age.

Results: Vascular density was found to significantly decrease over time (coefficient -177.05, p>0.001). 28 out of the 37 infants developed BPD (75.7%). In a mixed-effects linear regression analysis, increased vessel length density, a frequently used metric of peripheral microvascular density, was significantly correlated with the development of BPD (coefficient 1721.87, p=0.002).

Conclusions: Our data support the concept that increased nailfold microvascular density assessed with capillaroscopy in the first month of life can help identify infants at risk for developing BPD. This study also offers additional insight into neonatal microvasculature and could help develop future studies aimed at understanding of the underlying pathophysiology of BPD.