To investigate trends in the occurrence of severe, food-induced allergic reactions

Date of Approval: 
2020-08-18 00:00:00
Lay Summary: 
Food Allergy (FA) and Food Hypersensitivity (FHS) (including food allergies and intolerances) is common (affecting around 3-4% of the UK population) and can cause anaphylaxis which can be fatal. Anaphylaxis is a serious allergic hypersensitivity reaction that is usually rapid in onset and may cause death. Severe anaphylaxis is characterized by potentially life-threatening compromise in breathing and/or the circulation, and may occur without typical skin features or shock being present. In this work we will investigate how common food hypersensitivity is, and how this has changed over time. In particular, we will look at how different sorts of food hypersensitivity are managed within the NHS, for example who initially presents to primary care rather than secondary care (and vice versa), and what factors contribute to hospital admission. We will do this by studying linked Primary and Secondary care records and linked ONS mortality data from CPRD.
Technical Summary: 
This work will address a key question: what are the trends in the occurrence of food hypersensitivity reactions, including consequential health encounters (both hospital and primary care), using existing NHS datasets. Specifically, we will: i. Attempt to establish the accuracy/validate the different codes used in primary and secondary care for food hypersensitivity, to guide future use of NHS datasets to monitor trends in epidemiology. ii. Assess linked Primary and Secondary care records from CPRD (with respect to NHS encounters: primary care; Accident & Emergency visits; hospital admissions) due to food hypersensitivity over the past 10 years, in order to assess the trends in food hypersensitivity reactions in England (and where data can be accessed, for the devolved nations). iii. Investigate patient pathways with respect to health encounters
Health Outcomes to be Measured: 
- Prevalence and Incidence of Food Hypersensitivity (FHS) (and its various subtypes) in the last 10 years in the UK - Within patients with FHS, the number of healthcare encounters due to food hypersensitivity over the past 10 years presenting to primary versus secondary care in England and how this has changed year on year - Number of encounters for near-fatal food allergy (as measured by HDU and/or ICU admission) and death from anaphylaxis (in-hospital death) - Cost of healthcare encounters
Application Number: 
20_156
Collaborators: 

Jennifer Quint - Chief Investigator - Imperial College London
Constantinos Kallis - Corresponding Applicant - Imperial College London
Paul Turner - Collaborator - Imperial College London
Sadia Haider - Collaborator - Imperial College London

Linkages: 
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation