Epidemiology of allergic rhinitis in England: A retrospective cohort study in UK primary care data.

Study type
Protocol
Date of Approval
Study reference ID
24_003814
Lay Summary

Allergic rhinitis (AR) is the medical term given for inflammation of the nasal lining caused by an allergic trigger and can lead to developing asthma. Symptoms are varied but can include sneezing, an itchy nose, congestion (blocked, stuffy, or runny nose), and coughing. In recent years the number of people suffering from this condition have increased leading to a higher burden on the health care system. Reducing exposure to allergic triggers and use of over-the-counter (OTC) medicines can alleviate symptoms; however, when triggers are not immediately obvious, or OTC medicines don’t help, allergy testing becomes necessary. Patients are typically referred to specialist units for testing, diagnosis and management. This sometimes results in patients grappling with persistent symptoms while awaiting their referral appointment date.
This study aims to understand the scale and extent of AR in England by exploring patient trajectories in the healthcare system and examining outcomes.

The study findings will enhance our understanding on the frequency of AR in England, its management, and serve as a valuable resource for healthcare resource planning in the context of respiratory diseases.

Technical Summary

AR is a common condition affecting 10-15% of children and 26% of adults in the UK. Although often regarded as a trivial problem, it significantly affects quality of life, work, school performance and attendance, and is a risk factor for the development of asthma. Allergic rhinitis has tripled in the last 20 years resulting in considerable health care utilisation. By reducing triggers, symptoms can be controlled, reducing hospital visits and the risk of developing asthma. Currently, patients are typically referred to a hospital specialist for testing, which can cause delays in diagnosis, putting pressure on primary care in the intervening period, because of poorly controlled symptoms. The aim of this study is to describe the burden and unmet need of AR among patients in England from 2009-2019. The proposed study will look at epidemiology of AR and how its symptoms are managed within the health care system. Data sources include CPRD Aurum linked to secondary data. Hospital episodes statistics (HES) admitted patient care (APC) and HES outpatient (OP) records will be used to determine hospitalisations and health care usage, while patient index of multiple deprivation (IMD) will be used to provide baseline deprivation status. Descriptive analyses will include incidence of rhinitis symptom presentation, incidence of AR diagnosis and referral rates. The number of general practitioner (GP) appointments and hospitalisation rates will be used to understand the primary care and secondary care resource use associated with the study population. The study will enhance our understanding of the burden of AR in England. It will also highlight the barriers and opportunities for provision of improved health care services for patients with AR.

Health Outcomes to be Measured

AR incidence; AR presentation incidence; Asthma incidence; referral records for AR; primary healthcare HCRU associated with AR and AR presentation, assessed by:
a) GP consultations, including telephone consultations.
b) Hospital inpatient admissions
c) Referrals to specialists

Collaborators

Diane Hatziioanou - Chief Investigator - CPRD
Chisomo Mutafya - Corresponding Applicant - CPRD
Daphne Martin - Collaborator - CPRD
Hilary Shepherd - Collaborator - CPRD
Michael Jones - Collaborator - Thermo Fisher Scientific Inc.
Rachael Williams - Collaborator - CPRD

Linkages

HES Admitted Patient Care;HES Outpatient;Patient Level Index of Multiple Deprivation