Parental migration, socioeconomic deprivation and hospital admissions in preschool children: national cohort study

Background A third of children born in England have at least one parent born outside the UK, yet family migration history is infrequently studied as a social determinant of child health. We describe differences in rates of hospital admissions in children aged up to five years by parental migration and socioeconomic group. Methods Birth registrations linked to Hospital Episode Statistics were used to derive a cohort of 4,174,596 children born in state-funded hospitals in England between 2008 and 2014, with follow-up until age five years. We looked at eight maternal regions of birth, maternal country of birth for the 6 most populous groups and parental migration status for the mother and second parent (UK-born/non-UK-born). We used Index of Multiple Deprivation (IMD) quintiles to indicate socioeconomic deprivation. We fitted negative binomial/Poisson regression models to model associations between parental migration groups and the risk of hospital admissions, including interactions with IMD group. Findings Children of UK-born (73.6% of the cohort) mothers had the highest rates of emergency admissions (171.6 per 1000 child-years, 95% confidence interval (CI) 171.4-171.9), followed by South Asia-born mothers (155.9 per 1000, 95% CI 155.1-156.7). The high rates estimated in the South Asia group were driven by children of women born in Pakistan (186.8 per 1000, 95% CI 185.4, 188.2). A socioeconomic gradient in emergency admissions was present across all maternal region of birth groups, but most pronounced among children of UK-born mothers (incidence rate ratio 1.43, 95% CI 1.42-1.44, high vs. low IMD group). Overall, children whose parents were both born abroad had lower emergency admission rates than children whose parents were both born in the UK. Patterns of planned admissions followed a similar socioeconomic gradient and were highest among children with mothers born in Middle East and North Africa, and South Asia. Interpretation This research indicates that children whose parents who have migrated to the UK generally have lower overall usage of NHS emergency inpatient services than children of UK-born parents. Our study revealed a socioeconomically graded patterns of hospital admissions for all children born in England, which were highest amongst those with mothers born in the UK, South Asia, and the Middle East and North Africa. Future research using linked primary and secondary care datasets will improve understanding on whether healthcare use is proportionate to need. Funding National Institute for Health Research. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement KL & SN were supported by the National Institute for Health Research (NIHR) School for Public Health Research (Grant Reference Number PD-SPH-2015). The NIHR School for Public Health Research is a partnership between The University of Sheffield; University of Bristol; University of Cambridge; Imperial College London and University College London; London School for Hygiene & Tropical Medicine (LSHTM); LiLaC, a collaboration between the University of Liverpool and Lancaster University; and Fuse, The Centre for Translational Research in Public Health which is a collaboration between the Newcastle University, Durham University, Northumbria University, University of Sunderland and Teesside University. Research at UCL Great Ormond Street Institute of Child Health is supported by the NIHR Great Ormond Street Hospital Biomedical Research Centre (grant reference number IS-BRC-1215-20012). This research benefits from and contributes to the NIHR Children and Families Policy Research Unit but was not commissioned by the NIHR Policy Research Programme. Sonia Saxena is supported by the NIHR Northwest London ARC (202322), NIHR School for Public Health Research (NIHR 204000) and holds an NIHR Senior Investigator Award. The development of the City Birth Cohort was funded as part of NIHR "Births and their outcomes by time, day and year: a retrospective birth cohort data linkage study" HSDR 12/136/93. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: We have obtained ethical or information governance approvals from the following committees: NHS London Queen Square Ethics Committee (full approval, reference: 18/LO/1514); Confidentiality Advisory Group (full approval, reference: 18/CAG/0159); Administrative Data Research Network (approval, reference PROJ-194); ONS Research Accreditation Panel (full approval, reference 2019/020); National Statisticians Data Ethics Advisory Committee (full approval, reference: 18 (07)); Independent Group Advising on Release of Data (NHS Digital; full approval, DARS-NIC-234656). Approvals for the City Birth Cohort were obtained as follows. Ethics approval 05/Q0603/108 and subsequent substantial amendments were granted by East London and City Local Research Ethics Committee 1 and its successors. Permissions to use patient identifiable data without consent PIAG 2-10(g)/2005 and CAG 9-08(b) 2014 were granted by the Confidentiality Advisory Group and its predecessors. Permission to access data from the Office for National Statistics in the VML, now known as the Secure Research Service was granted by ONSs Microdata Release Panel, now superseded by its Research Advisory Panel. Permission to link and analyse data held by the Health and Social Care Information Centre, now known as NHS Digital, was granted under Data Sharing Agreements NIC-273840-N0N0N and subsequently under DARS-NIC-10094-P6P4B-v6.7 I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes The authors do not have permission to supply data or identifiable information to third parties. Anyone wishing to access the linked datasets for research purposes should apply via the CAG to the Health Research Authority to access patient-identifiable data without consent and then to the ONS and NHS Digital. In the first instance, enquiries about access to the data analysed here should be addressed to the corresponding author and enquiries about the City Birth Cohort should be addressed to Alison Macfarlane (A.J.Macfarlane{at}city.ac.uk). * AIC : Akaike Information Criterion GP : General practitioner HES APC : Hospital Episode Statistics Admitted Patient Care ICD-10 : International Classification of Diseases 10th Revision IDACI : Income Deprivation Affecting Children Index IRR : Incidence Rate Ratio NHS : National Health Service MCS : Millennium Cohort Study ONS : Office for National Statistics