Dr Vanessa Murphy1,2, Dr Megan Jensen1,2, Dr Michael Peek3, Dr Annelies Robijn1,2, Dr Bronwyn Brew1,2, Ms Kelly Steel1,2, Breathing for Life Trial Collaborative Group, Dr Peter Gibson1,2,4
1University Of Newcastle, Callaghan, Australia, 2Hunter Medical Research Institute, New Lambton Heights, Australia, 3University of Sydney, Camperdown, Australia, 4John Hunter Hospital, New Lambton Heights, Australia
Biography:
A/Prof Vanessa Murphy from the University of Newcastle is a research scientist investigating the characteristics, mechanisms and consequences of asthma exacerbations during pregnancy and their health impact on both mother and baby. She is deputy chair of the Hunter Medical Research Institute's Asthma and Breathing Program.
Abstract:
Infants whose mothers have asthma are at increased risk of neonatal hospitalisation; however, the mechanisms are unknown, and no studies have examined characteristics of admission. We aimed to describe admission characteristics of this group and determine any associations with maternal asthma control or exacerbations.
Infants (n=733) of mothers with asthma (n=716) enrolled in the Breathing for Life Trial (BLT) in Newcastle (2013-2019) were included. Neonatal admission details were obtained from medical records. Maternal asthma control was assessed mid-pregnancy, and exacerbations (hospital admission, emergency presentation, oral corticosteroids or unscheduled GP visit) assessed retrospectively after pregnancy.
Neonatal hospitalisation occurred in 95/733 (13.0%) infants (57% male, 22% from multiple births, 59% Level II Special Care Nursery [SCN], 41% Level III Neonatal Intensive Care Unit [NICU]). The most common primary admission diagnosis was prematurity (46.3%), followed by respiratory distress (32.6%). Mean (SD) birthweight was 2570 (883) grams, gestational age was 35.3 (3.5) weeks; 58% of infants were preterm, 14% were <1500g, 84% required resuscitation and 71% had respiratory distress. Median length of stay was 4 days (IQR 2–14).
Compared to NICU babies in the 2020 Report of the Australian and New Zealand Neonatal Network (ANZNN), BLT babies were significantly more likely to be <1500g (46% vs 25%, P=0.004). SCN babies in BLT were more likely to be born by caesarean than ANZNN SCN infants (70% vs 45%, P<0.0001).
Compared to mothers of infants who were not admitted, mothers of infants admitted to NICU/SCN were more likely to have had an asthma exacerbation during pregnancy (33.7% vs 23.4%, P=0.029), had more exacerbations (P=0.037), and were more likely to have had uncontrolled asthma in mid-pregnancy (70.5% vs 38.8%, P<0.0001).
This is the first study to show that poor asthma control and exacerbations during pregnancy are associated with neonatal hospitalisation. Reducing exacerbations may improve neonatal outcomes.
Keywords
Asthma, NICU, prematurity