Re: "Neonatal Bilirubin Levels and Childhood Asthma in the US Collaborative Perinatal Project, 1959-1965"
Year: 2014
Type: letter
Abstract: We read with interest the paper by Huang et al. (1) suggesting that neonatal jaundice is associated with childhood asthma. Using data from the Collaborative Perinatal Project (CPP), Huang et al. examined whether the associations between neonatal jaundice and childhood asthma could be due to phototherapy (which was unavailable at the time of the CPP) or a high bilirubin level itself, but the accompanying commentary (2) raised the issue of a potential common cause for both childhood asthma and hyperbilirubinemia, among other possible explanations. We suggest that such a common cause is likely to be maternal asthma, based on our recent findings on the neonatal health of infants born to mothers with asthma (3). We found an increased risk of hyperbilirubinemia (odds ratio = 1.09, 95% confidence interval: 1.04, 1.14) associated with maternal asthma after adjustment for detailed demographic and clinical information from a large US cohort study of electronic medical records. Given that maternal asthma is known to increase the risk of asthma among offspring (4), maternal asthma is a plausible common cause that has not (to our knowledge) been considered in the literature. These relationships are bound to be complex, and careful attention is needed to properly model the potential confounders and mediators of maternal-infant-childhood associations (5). In this case, Huang et al. adjusted their results for maternal allergic conditions (1), but this is a poor proxy for maternal asthma, since about half of current asthma is nonallergic and perhaps 30% of nonasthmatics have a common allergy response. On the other hand, we recognize that the differences between asthma diagnosis and treatment in the 1960s and in the present day add further complexity to the interpretation of these findings. This is an intriguing area of research, and given the high prevalence of asthma in contemporary pregnancy cohorts, it merits further attention. Conflict of interest: none declared.
Source: American Journal of Epidemiology
DOI: 10.1093/aje/kwu064
Authors: P. Mendola, S. K. Laughon, T. I. Mannisto
Language: English
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W2112257800