Association between maternal influenza vaccination and neurodevelopmental disorders in childhood: a longitudinal,
Damien Foo1,2, Mohinder Sarna3,2, Gavin Pereira3,4
1Curtin School of Population Health, Curtin University, Perth, Western Australia, Australia Damien.Foo@curtin.edu.au.
Insights
Maternal influenza vaccination during pregnancy (in utero inactivated influenza vaccine exposure) did not increase the risk of neurodevelopmental disorders in children. Some evidence suggests lower risks for seizure and sleep disorders with prenatal IIV exposure.
Area of Science:
- Obstetrics and Gynecology
- Pediatrics
- Epidemiology
Background:
- Prenatal exposure to vaccines is a growing area of research.
- Understanding the safety of maternal influenza vaccination is crucial for public health.
- Neurodevelopmental disorders impact a significant number of children globally.
Purpose of the Study:
- To assess the association between in utero exposure to seasonal inactivated influenza vaccine (IIV) and the risk of neurodevelopmental disorders in early childhood.
- To investigate potential risks or benefits of maternal IIV during pregnancy.
Main Methods:
- Retrospective cohort study utilizing a population-based birth registry linked with health administrative databases in Western Australia.
- Included singleton, liveborn children born between April 2012 and July 2016.
- Used Cox proportional hazard regression, weighted by inverse-probability of treatment, to estimate hazard ratios for neurodevelopmental disorders associated with in utero IIV exposure.
Main Results:
- The study included 140,514 children, with 11.2% exposed to IIV in utero.
- Maternal IIV was not associated with an increased risk of overall neurodevelopmental disorders (HR 1.00; 95% CI 0.91 to 1.08).
- Children exposed in the first trimester showed a lower risk of seizure disorders (aHR 0.73), and preterm children exposed anytime during pregnancy had a lower risk of sleep disorders (aHR 0.63).
Conclusions:
- In utero exposure to seasonal inactivated influenza vaccine is not associated with an increased risk of neurodevelopmental disorders.
- Preliminary evidence suggests potential protective effects against seizure and sleep disorders, warranting further investigation.
- Maternal influenza vaccination remains a safe and recommended public health intervention during pregnancy.
Objective:
To assess the association between in utero exposure to seasonal inactivated influenza vaccine (IIV) and the risk of a diagnosis of a neurodevelopmental disorder in early childhood.
Design:
Retrospective cohort study.
Setting:
Population-based birth registry linked with health administrative databases in Western Australia (WA).
Participants:
Singleton, liveborn children born between 1 April 2012 and 1 July 2016 in WA.
Exposure:
Receipt of seasonal IIV during pregnancy obtained from a state-wide antenatal vaccination database.
Main Outcome Measures:
Clinical diagnosis of a neurodevelopmental disorder was recorded from hospital inpatient and emergency department records. We used Cox proportional hazard regression, weighted by the inverse-probability of treatment (vaccination), to estimate the hazard ratio (HR) of neurodevelopmental disorders associated with in utero exposure to seasonal IIV.
Results:
The study included 140 514 children of whom, 15 663 (11.2%) were exposed to seasonal IIV in utero. The prevalence of neurodevelopmental disorders was 5.4%, including mental or behavioural (0.4%), neurological (5.1%), seizure (2.2%) and sleep disorders (2.7%). Maternal IIV was not associated with increased risk of neurodevelopmental disorders (HR 1.00; 95% CI 0.91 to 1.08). Children exposed in the first trimester had a lower risk of seizure disorders (adjusted HR [aHR] 0.73; 95% CI 0.54 to 0.998), and preterm children exposed any time during pregnancy had a lower risk of sleep disorders (aHR 0.63; 95% CI 0.41 to 0.98).
Conclusions:
We did not observe increased risk of neurodevelopmental disorders following in utero exposure to seasonal IIV. Although we observed some evidence for lower risk of seizure and sleep disorders, additional studies are required to confirm.
