Invited commentary: does neonatal hyperbilirubinemia cause asthma?

Area of Science:

• Neonatal Medicine
• Pediatric Pulmonology
• Genetic Epidemiology

Background:

• A previous study identified an association between neonatal total serum bilirubin levels and childhood asthma.
• The potential clinical implications necessitate an evaluation of the causality of this observed association.

Purpose of the Study:

• To critically assess the findings by Huang et al. regarding neonatal bilirubin levels and childhood asthma.
• To explore potential confounding factors, such as genetic polymorphisms, that may influence the observed association.
• To emphasize the need for further research to establish causality and evaluate the efficacy of interventions.

Main Methods:

• Analysis of data from the US Collaborative Perinatal Project.
• Review of existing literature on neonatal hyperbilirubinemia, asthma, and genetic factors.
• Exploration of potential confounding variables, including glutathione S-transferase gene polymorphisms.

Main Results:

• The association between neonatal bilirubin levels and childhood asthma does not appear to be due to chance or obvious bias.
• Confounding by a common cause, potentially genetic factors like the glutathione S-transferase M1-null phenotype, is a likely explanation for the observed association.
• The glutathione S-transferase M1-null phenotype has been previously linked to both neonatal hyperbilirubinemia and asthma.

Conclusions:

• The observed association between neonatal bilirubin levels and childhood asthma warrants further investigation to determine causality.
• Interventions aimed at reducing peak bilirubin levels require careful evaluation to confirm their impact on asthma risk and rule out adverse effects.
• Further research is crucial before implementing clinical practice changes based on the current findings.