Study Links Maternal Asthma to Blinding Eye Disease in Premature Infants

Maternal asthma could increase the likelihood of a blinding eye disease in premature infants, according to a new study.

Presented at the 42nd American Society of Retina Specialists (ASRS) Annual Scientific Meeting, results of the study, which leveraged data from more than 2000 infants screened for retinopathy of prematurity, indicate premature infants born to mothers with asthma exhibited a greater risk of advanced retinopathy of prematurity.¹

“Premature infants of mothers with asthma are more likely to have more advanced [retinopathy of prematurity] and are more likely to require treatment,” wrote investigators.¹ “These observations remained significant when controlling for the known risk factors of ROP including gestational age and birth weight.”

The severity of retinopathy of prematurity is defined using staging criteria, with stag 1 indicating mild retinopathy of prematurity and stage 5 indicative of severe retinopathy of prematurity. Most babies in stage 1 and stage 2 will recover on their own and go on to have healthy vision. In contrast, babies in stage 5 will have a completely detached retina and may have vision loss or blindness.^1,2

As investigators, who were led by Zafar Gill, MD, University of Colorado, outline, associations between retinopathy of prematurity and factors such as birth weight and gestational age have been well-documented. In contrast, much less research has elucidated links between other factors, such as specific aspects of maternal health and wellness.^1,2

With this in mind, investigators designed their study a retrospective analysis of observational data obtained from the University of Colorado ROP Screening Registry. Using the registry, investigators identified 2132 infants screened for retinopathy of prematurity between January 2006 through June 2023. Of note, the registry pooled data from infants screened in neonatal intensive care units at the University of Colorado hospital and Children's Hospital Colorado.¹

Among the infants who underwent screening and were included in the study, 13.2% were born to mothers with asthma.¹

The primary outcome of interest for the investigators’ analysis was whether a maternal history of asthma and its potential association with a hypoxic prenatal environment may impact the development and severity of retinopathy of prematurity. For the purpose of analysis, investigators expressed the likelihood of each outcome of interest using odds ratios (ORs) and 95% confidence intervals (CI) using logistic regression models.¹

Upon analysis, which included adjustment for gestational age and birth weight, results indicated infants born to mothers with asthma were more likely to have stage 1 (OR, 1.77; 95% CI, 1.15 to 2.74; P = .01), stage 3 (OR, 1.85; 95% CI, 1.12 to 3.04; P = .02), and stage 4 ROP (OR, 11.1; 95% CI, 2.50 to 48.9; P <.01) compared to stage 0.¹

Further analysis demonstrated neonates born to mothers with asthma were more likely to have type 1 (OR, 2.12; 95% CI, 1.13 to 3.98; P = .02) and type 2 (OR, 2.06; 95% CI, 1.18 to 3.58; P = .01) retinopathy of prematurity than neonates born to mothers without asthma. Additionally, results also indicated neonates born to mothers with asthma were more likely to require treatment for retinopathy of prematurity (OR, 1.78; 95% CI, 1.06 to 2.97; P = .03).¹

Investigators highlighted their study had multiple limitations to consider when interpreting its findings. These included being limited to 2 centers, being retrospective in nature, and lacking data on factors such as asthma severity and hypoxia during pregnancy.¹

“We suggest that maternal asthma influences the oxygen environment in utero and is an independent risk factor for the development of [retinopathy of prematurity],” investigators wrote.¹ “While this study represents a first step towards examining the relationship between asthma and [retinopathy of prematurity], further studies are needed to better understand how and why it influences the disease.”

References:

1. Gill Z, Oliver S, Mathias M, et al. The Effect of Maternal Asthma on Retinopathy of Prematurity.Paper presented at the American Society of Retina Specialists (ASRS) 42nd Annual Meeting. Stockholm, Sweden. July 17-20, 2024.
2. National Institutes of Health. Retinopathy of prematurity. National Eye Institute. Accessed July 21, 2024. https://www.nei.nih.gov/learn-about-eye-health/eye-conditions-and-diseases/retinopathy-prematurity.