Chronic obstructive pulmonary disorder (COPD) is a common preventable lung disease, often caused by air pollution or smoking. The disease can limit airflow through the lungs, causing symptoms such as coughing, shortness of breath, wheezing, and chest tightness. COPD was the third highest cause of death in England and Wales in 2022.
The body’s immune system responds to COPD by producing white blood cells called eosinophils. Some evidence suggests that patients with a high amount of eosinophils are more likely to experience more severe symptom flare-ups.
Treatment is personal for each patient depending on the progression of COPD. Patients are given maintenance therapy to help keep airways open and prevent symptom flare-ups. Patients who commonly have symptom flare-ups are recommended inhalers which combine two types of drug called dual therapy inhalers, or, if dual therapy inhalers do not control symptoms, they are recommended inhalers which combine three types of drug, called triple therapy inhalers. In the UK, patients receiving triple therapy inhalers for COPD who still experience symptom flare-ups have few further options to control their COPD, while no treatments aim to reduce eosinophil levels.
Due to some remaining questions in research on the role of eosinophils in COPD presentation and the lack of treatment options for patients on maximum strength therapy, it is important to understand the impact of eosinophil levels on symptom flare ups, to help manage COPD patient care in England.
Aim: To describe the disease burden and healthcare resource utilisation (HCRU) among patients aged ≥35 years in England diagnosed with COPD who exacerbate frequently, stratified by blood eosinophil count (BEC).
Objectives: Among patients with COPD who are frequent exacerbators, to: i) describe disease burden and health outcomes among patients on triple therapy, overall and by baseline BEC; ii) examine the baseline sociodemographic and clinical predictors of BEC testing status among patients on triple therapy; iii) examine the impact of BEC on health or disease burden outcomes among patients on triple therapy; and iv) describe sociodemographic, clinical and treatment characteristics among patients on: a) triple therapy, b) ICS/LABA, c) LAMA/LABA, and d) triple therapy who are former smokers, overall and by baseline BEC.
Methods: Retrospective analysis of longitudinal healthcare data in England utilising linked primary and secondary care data from Clinical Practice Research Datalink (CPRD) Aurum and Hospital Episode Statistics (HES) datasets, respectively.
Index criteria: The most recent moderate/severe exacerbation of COPD (AECOPD) (≥1 moderate/severe AECOPD in the year prior if the most recent AECOPD was moderate).
Covariates: Index year; baseline sociodemographic and clinical characteristics (age, gender, region, ethnicity, deprivation, body mass index (BMI), forced expiratory volume, smoking status, Charlson Comorbidity Index (CCI), MRC dyspnoea score); baseline all-cause primary and secondary care HCRU events; baseline respiratory therapies.
Outcomes: AECOPD; Mortality; HCRU and associated direct healthcare costs; BEC testing status; sociodemographic and clinical characteristics.
Data analysis: For descriptive analysis, counts, means, medians, standard deviation (SD), 25th and 75th percentile values will be reported for continuous variables, with relative frequencies and proportions/percentages for categorical variables. For inferential analyses, i) a multivariate logistic regression will examine predictors of BEC testing status, and ii) appropriate regression models and a PS weighting method will evaluate the impact of BEC on disease and clinical outcomes.
Acute exacerbations of COPD (AECOPD); Mortality; Healthcare Resource Use (HCRU) and associated direct healthcare costs; BEC testing status.
Jihye Park - Chief Investigator - GlaxoSmithKline LLC (USA)
Poppy Payne - Corresponding Applicant - Adelphi Real World
James Bolaji - Collaborator - GlaxoSmithKline - UK
Jennifer Quint - Collaborator - Imperial College London
Olivia Massey - Collaborator - Adelphi Real World
Shibing Yang - Collaborator - GSK
Theo Tritton - Collaborator - Adelphi Real World
Will Kay - Collaborator - Adelphi Real World
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation