Atopic eczema may be associated with multiple health conditions. Here, we systematically explored risks across the full health spectrum based on the International Classification of Diseases, assessing associations between eczema and 2,058 ICD-10 codes, 1,593 phecodes, and 201 Global Burden of Disease codes.

In English primary care electronic health records (1997−2023) we identified cohorts of people with eczema (up to 3 million) and compared to matched comparators (individuals without eczema (by age, sex, general practice) (up to 14 million). In up to 25 years of follow-up, we captured outcomes recorded during hospital admissions.

People with eczema had higher rates of several outcomes across multiple organ systems. Among those followed up from eczema diagnosis in childhood, atopic/allergic conditions and infections accounted for most excess diagnoses. Besides skin and atopic/allergic outcomes, lymphomas, coeliac disease, inflammatory bowel conditions, and specific eye diseases had particularly large relative risk increases.

Julian Matthewman, Anna Schultze, Spiros Denaxas, Krishnan Bhaskaran, and Amanda Roberts have no conflicts of interest to report relating to the findings. Sinæad M Langan is a co-investigator in a consortium with industry and multiple academic partners (BIOMAP-IMI.eu) but is not in receipt of industry funding. Kathryn E Mansfield reports individual consulting fees from AMGEN.

This work uses data provided by patients and collected by the NHS as part of their care and support. This work was funded by a Wellcome Trust Senior Research Fellowship in Clinical Science (205039/Z/16/Z) awarded to Sinæad M. Langan. Krishnan Bhaskaran is funded by a Wellcome Senior Research Fellowship (220283/Z/20/Z). The views expressed in this publication are those of the author(s) and not necessarily those of the NIHR, NHS or the UK Department of Health and Social Care.

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The study was approved by the London School of Hygiene & Tropical Medicine Research Ethics Committee (Reference number: 29781). This study is based on data from the CPRD obtained under license from the U.K. Medicines and Healthcare products Regulatory Agency. The data are provided by patients and collected by the National Health Service (NHS) as part of their care and support. The study was approved by the Independent Scientific Advisory Committee (Protocol reference number: 23_002665). Individual patient consent is not required or possible since CPRD provides anonymised data. Consent is given by the GP practices that contribute data to CPRD. Individual patient consent is implied. However, patients are offered the right to opt out from the use of their pseudonymised data.

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