Air Pollution, housing and respiratory tract Infections in Children: NatIonal birth Cohort study (PICNIC)

Lead Research Organisation: University College London
Department Name: Institute of Child Health

Abstract

What is this research project about?

We will investigate to what extent exposure to air pollution during pregnancy and the first five years of life and poor housing conditions (such as overcrowding and damp/mould) contribute to hospital admissions for respiratory tract infections (RTIs) in children less than five years old.

Why are we doing this research?

RTIs, including bronchiolitis, pneumonia and croup, are the most common reason for hospital admission in young children in the UK. These admissions are stressful for children, their parents and costly for the National Health Service (NHS). Being admitted to hospital with an RTI during the first few years of life is also associated with the development of chronic respiratory problems, such as asthma, in later childhood. Previous research has found that children from poor backgrounds are more likely to need an RTI admission, but it is not clear which aspects of children's living conditions make the largest contribution to RTI hospital admissions. In this study, we will examine whether exposure to air pollution in the womb or during early childhood, and poor housing conditions are associated with a child's risk of being admitted to hospital with an RTI. Also, we will look at how many RTI admissions could be prevented in the UK if we reduced air pollution and/or improved housing conditions for families with young children.

How are we going to do it?

We will use data collected from birth certificates, linked to maternity records and hospital admission data for all children born in England between 2005 and 2014, and Scotland between 1997 and 2019: 8 million children in total. We will link in data about children's air pollution exposure during pregnancy and childhood, building characteristics, and information about housing and socio-economic background from the 2011 Census. All data will be kept on secure servers and linked using methods that protect the identities of mothers and children.

We will use these data to examine whether exposure to air pollution and poor housing conditions are associated with an increased risk of being admitted to hospital with an RTI during the first five years of life. We will use statistical methods that allow us to take into account whether children have other underlying risk factors for RTI hospital admissions, such as chronic health problems. We will also make sure that other researchers can access these datasets to carry out maternal and child health research in the future.

Technical Summary

Respiratory tract infections (RTIs) are the most common reason for hospital admissions in children under five in the UK. We aim to quantify the extent to which in-utero, infant and childhood exposure to air pollution (AP), and adverse housing conditions (including overcrowding and damp/mould) are associated with the risk of RTI admissions in children less than 5 years old.

We will use national administrative data birth cohorts including all children born in England in 2005-2014, and in Scotland 1997-2019, created via linkage between vital statistics, maternity and hospital admission datasets. We will further enhance these cohorts via linkage to Census 2011 data from mothers and their partners on housing conditions and socio-economic position, and small-area level data on AP and building characteristics. Our specific objectives are to:

1) Estimate the association between long-term exposure to ambient AP during pregnancy and infancy and the rate of RTI admissions in infants
2) Derive variables indicating adverse housing conditions (eg overcrowding, indoor air pollution, damp/mould) and estimate the association between housing exposures and infant RTI admissions
3) Based on the outcomes of analyses for objectives 1) and 2), estimate the relative contribution of AP and adverse housing conditions on infant RTI admissions
4) Estimate the relative contribution of AP exposure during pregnancy, infancy and early childhood and adverse housing conditions on RTI admissions in children aged less than five years
5) Establish the linked administrative data birth cohorts as resources for maternal and child health research

Our results will inform policy makers, charities and parents about the relative contribution of AP exposure during pregnancy, infancy and early childhood and housing conditions to RTI admissions in children. Our legacy will include the two national birth cohorts, which will be made available to other researchers.

Planned Impact

RTIs are the most common reason for being admitted to hospital among children under 5 years in the UK, with over 195,000 children admitted annually. These admissions are costly: the annual bill for NHS England due to bronchiolitis alone has been estimated at £84 million. Due to their seasonal nature, RTI admissions cause pressure on accident and emergency departments, and acute assessment and paediatric wards, during the winter.

Our results therefore have potential to improve the respiratory health of children and the environments in which they grow up, and reduce health inequalities in early life. A reduction in RTI admissions will also reduce stress for parents and costs for the NHS. This study therefore has potential to impact on a number of different stakeholders:

Researchers in public, respiratory and maternal and child health: In the short term, researchers in these fields will benefit both from the research findings, and from the national administrative data birth cohorts, linked to Census and small-area level exposure data, which will be made available to other research groups.

Local authorities, housing associations and NHS organisations: Local authorities across England and Scotland are responsible for housing, and reviewing and assessing local air quality. English Local Authorities and Scottish Health Boards are also responsible for monitoring and improving public health in the local area. This project will provide information on the relative importance of risk factors including overcrowding and air pollution to common childhood hospital admissions, providing a sound evidence base for prioritising spending locally in order to improve childhood respiratory health. We will ensure our study results are relevant to local policy makers by carrying out subnational analyses where possible.

Central government (including the Scottish Government, Homes England, Public Health England, Department of Health, NHS Health Scotland): Our findings will provide evidence for national policies to improve children's health, reduce health inequalities and suggest methods for monitoring policy impact at national and local level.

Data providers (including Office for National Statistics, National Records for Scotland and NHS Digital): In the short-to-medium term, the project will identify the Census variables that are most strongly associated with young children's health and therefore need to be captured through other administrative data sources when the Census is phased out after 2021. Our study will also emphasise the utility and importance of linking datasets from different data providers for health research, thereby motivating data sharing and improved access to linked datasets for researchers.

Parents and voluntary sector organisations: This project will provide parents with information about the relative contribution of adverse housing conditions and air pollution to RTI hospital admissions in children. This evidence base can empower parents and voluntary sector organisations to push for improvements in local environments and housing quality.

Research staff & lecturers employed on the project: In the short term, this project will build capacity for data linkage, governance, and administrative data analysis for the research fellow and the data manager working on the project. The three lecturers (PH, TC and AM) leading the project will develop collaborations with senior experts (co-Is and collaborators). This project will therefore contribute to health data science capacity in the UK.

Publications

10 25 50
 
Description Cohort for research into Living EnVironments and hEalth in childRen: CLEVER
Amount £933,400 (GBP)
Funding ID ES/X000311/1 
Organisation Economic and Social Research Council 
Sector Public
Country United Kingdom
Start 12/2022 
End 12/2025
 
Description HDR UK QQ2 - Social And Environmental Determinants Of Health Demonstrator Programmes
Amount £499,974,154 (GBP)
Organisation Health Data Research UK 
Sector Private
Country United Kingdom
Start 03/2023 
End 03/2028
 
Description What is the association between exposure to air pollution and adverse housing conditions, with viral respiratory infections in young children?
Amount £95,411 (GBP)
Organisation The Child Health Research Charitable Incorporated Organisation 
Sector Academic/University
Country United Kingdom
Start 09/2022 
End 09/2025
 
Description houSing feaTures and Risk of Injury in chilDrEn (STRIDE)
Amount £17,630 (GBP)
Organisation University College London 
Sector Academic/University
Country United Kingdom
Start 02/2022 
End 06/2022
 
Description Collaboration on air pollution and Child Health and England and Sweden 
Organisation Umea University
Country Sweden 
Sector Academic/University 
PI Contribution We have begun a collaboration regarding comparative analyses of the impact of air pollution and child health in Sweden and the UK
Collaborator Contribution We will carry out comparative analyses using linked administrative datasets from the above countries
Impact No outputs yet
Start Year 2021
 
Description Collaboration with Public Health Scotland on COVID19 epidemiology in children 
Organisation Public Health Scotland
Country United Kingdom 
Sector Public 
PI Contribution As a result of the COVID19 pandemic, we begun a collaboration with Public Health Scotland (PHS) to examine the epidemiology of COVID19 disease in children using the Scottish PICNIC data.
Collaborator Contribution PHS have provided input to the protocol and to the PBPP application (application to access data for the project).
Impact No outputs yet
Start Year 2020
 
Description PICNIC has joined the HEICCAM network 
Organisation University of Edinburgh
Country United Kingdom 
Sector Academic/University 
PI Contribution PICNIC is now a partner in the UKRI funded HEICCAM network (https://heiccam.org/).
Collaborator Contribution I have spoken at the HEICCAM annual conference about PICNIC, which allowed scholars in housing quality to learn about PICNIC.
Impact -Presentation about PICNIC at HEICCAM annual conference
Start Year 2022
 
Description PICNIC has joined the HEICCAM network 
Organisation University of Edinburgh
Country United Kingdom 
Sector Academic/University 
PI Contribution PICNIC is now a partner in the UKRI funded HEICCAM network (https://heiccam.org/).
Collaborator Contribution I have spoken at the HEICCAM annual conference about PICNIC, which allowed scholars in housing quality to learn about PICNIC.
Impact -Presentation about PICNIC at HEICCAM annual conference
Start Year 2022
 
Description Support for Olivia Swann's Wellcome Trust fellowship application 
Organisation University of Edinburgh
Country United Kingdom 
Sector Academic/University 
PI Contribution The PI (PH) is a sponsor of Dr Olivia Swann's application for a Wellcome Trust Early Career Award.
Collaborator Contribution Dr Swann will further develop the PICNIC Scotland data
Impact N/A no outputs yet
Start Year 2023
 
Description Development of PICNIC website 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact We have developed a public facing website for the PICNIC study, including translations of the study material into multiple commonly spoken languages: https://www.ucl.ac.uk/child-health/picnic-study
Year(s) Of Engagement Activity 2020
URL https://www.ucl.ac.uk/child-health/picnic-study
 
Description Environmental epidemiology KS2 teaching materials development and delivery 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact We worked with an educational consultant to develop materials for kS2 school children about environmental epidemiology. We tested the materials with year 3 and year 6 students at assemblies in a school in south east London. The materials will be made freely available on TES.
Year(s) Of Engagement Activity 2023
 
Description Meeting with GOSH BRC Parents & Carers Group 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Patients, carers and/or patient groups
Results and Impact I consulted the GOSH BRC Parents and Carers' Research Advisory Group about their views on linking administrative data for environmental health research, and a sibling of one of the members subsequently helped develop an engagement strategy for secondary school children.
Year(s) Of Engagement Activity 2021
 
Description Presentation at GOSH Play Street event 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Patients, carers and/or patient groups
Results and Impact We presented the PICNIC project at the GOSH Play street event, and engaged with parents and children
Year(s) Of Engagement Activity 2023