Peer-reviewed article
Early-life lung function deficits partially explain the link between maternal asthma and bronchiolitis or asthma in offspring.
Da Silva Sena CR, Collison A, Murphy VE, Martins Costa Gomes G, Gorlanova O et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study examined how maternal asthma during pregnancy affects children's risk of bronchiolitis and asthma by looking at infant lung function as a possible explanation. Researchers measured lung function in newborns from two birth cohorts in Australia and Switzerland and tracked bronchiolitis hospitalizations and asthma diagnosis through age six. They found that reduced infant lung function was associated with both bronchiolitis and childhood asthma, and that impaired lung function partially explained why children of mothers with asthma have higher respiratory risks.
Key points
- 1,203 term infants were studied; 89 had bronchiolitis hospitalizations and asthma was assessed at age six
- Abnormal lung function ratios (MTIF/MTEF) were significantly associated with bronchiolitis hospitalization (adjusted OR 2.90)
- Lung function measures were also associated with childhood asthma diagnosis
- Impaired infant lung function mediated 11% of the effect of maternal asthma on bronchiolitis risk and 3% of the effect on childhood asthma risk
- The study demonstrates that early lung function deficits partially but not fully explain the respiratory risk from maternal asthma
Limitations
The study does not establish causation, only associations and partial mediation. The small number of bronchiolitis cases and reliance on parent-reported asthma diagnosis at age six limit the strength of conclusions about childhood asthma outcomes.
Abstract
Background Maternal asthma during pregnancy is associated with an increased risk of bronchiolitis and asthma in offspring, but the mechanisms remain poorly understood. We aimed to assess whether impaired postnatal infant lung function independently influences the risk of bronchiolitis and asthma in childhood or whether it mediates the association between maternal asthma during pregnancy and respiratory outcomes. Methods We analysed harmonised infant lung function data from two birth cohorts: the Australian Breathing for Life Trial and the Swiss Basel-Bern Infant Lung Development. Bronchiolitis hospitalisation (verified through medical records) and asthma at age six (parent-reported) were primary outcomes. Lung function measured included the ratio of maximum tidal inspiratory flow to maximum tidal expiratory flow (MTIF/MTEF) and the time to peak tidal expiratory flow to total expiratory time ratio, tPTEF/tE. Multivariable logistic regression assessed associations, and generalised structural equation modelling was used for mediation analyses. Results The study included 1203 term infants with 89 cases of bronchiolitis hospitalisation. Tidal breathing lung function ratios were associated with bronchiolitis hospitalisations: MTIF/MTEF adjusted ORs (aORs) 2.90, 95% CI 1.20 to 7.02, p=0.018; asthma in childhood: tPTEF/tE aOR 0.97, 95% CI 0.94 to 0.99, p=0.013 and MTIF/MTEF aOR 2.94, 95% CI 1.07 to 8.02, p=0.036. MTIF/MTEF ratio mediated 11% of the total effect of asthma during pregnancy on bronchiolitis risk, and MTIF/MTEF and tPTEF/tE ratios mediated 3% of the effect of asthma during pregnancy on childhood asthma risk. Conclusion Postnatal lung function was associated with subsequent bronchiolitis and childhood asthma. Additionally, the effect of maternal asthma during pregnancy on the outcomes was partially mediated by impaired lung function.
Findings the Hub has extracted
Each claim below is labelled by its type of design and links back to this report.
- Intervention
- Measurement of early-life lung function (tidal breathing patterns) to identify mediation pathway between maternal asthma and offspring respiratory outcomes
- Population
- 1,203 term infants from two birth cohorts (Australian Breathing for Life Trial and Swiss Basel-Bern Infant Lung Development)
Key finding
MTIF/MTEF ratio associated with bronchiolitis: adjusted OR 2.90 (95% CI 1.20-7.02, p=0.018)