Chronic Obstructive Pulmonary Disease (COPD) is a long-term but treatable disease of the lungs that develops gradually but is the third most common cause of death. Patients with COPD can experience a specific worsening of their symptoms called exacerbations from the usual state which can result in a reduced quality of life, additional treatments and mortality. Studies have shown that having frequent exacerbations can be predicted by having previous exacerbations.
COPD can be grouped in increasing stages according to their symptoms and history of exacerbations from Stage A – D with COPD patients in the latter stages of Group C and D having a high risk of exacerbations, hospital admissions or even death.
Studies have however shown that patients in the “low risk” group B still have substantial risk of poorer COPD outcomes such as hospital admission and death.
Other studies have suggested other coexisting illnesses, breathlessness symptoms and reduced airflow into the lungs can predict future COPD exacerbations. These have however been conducted with more severe COPD cases and not in less severe COPD cases (Group A and B COPD cases).
This study aims to use CPRD-AURUM and linked data to investigate risk factors related to the first exacerbations in COPD patients in Group A and B categories. In this way we will be able to locate opportunities for potential prevention efforts in early COPD patients.
Overarching aim and objectives: To identify risk factors which contribute to a first Chronic Obstructive Pulmonary Disease (COPD) (moderate, moderate/severe exacerbation and severe) exacerbation in UK Global Initiative for Chronic Obstructive Lung Disease (GOLD) A and B COPD patients overall, and by inhaled corticosteroid use at baseline. Study population of interest: GOLD A and B COPD UK patients from the linked Clinical Practice Research Datalink (CPRD) Aurum and Hospital Episode Statistics (HES) data. Primary exposures and outcome: Forced expiratory volume in one second (FEV1)% predicted, Medical Research Council (MRC) dyspnea scale, COPD Assessment Test (CAT) score, COPD GOLD grade of airflow limitation, GOLD 2020, moderate-severe Acute exacerbation of COPD (AECOPD) history, eosinophil levels, comorbidities, current asthma diagnosis, historical asthma diagnosis. Outcomes include risk of moderate, severe, moderate/severe exacerbations in 1 year, 3 year and 5 year follow up period. Data sources: CPRD-AURUM will be used to capture the majority of a patient’s COPD healthcare journey. HES (Admitted Patient Care) will be used to determine COPD patients that experience severe (hospitalised) events. Patient Level Index of Multiple Deprivation will be used to describe the baseline socioeconomic status of COPD patients and to enable adjustment for it. Study design, methods (statistical tests): A retrospective cohort study using CPRD Aurum linked to HES with follow up period from Jan 2013 to Dec 2019. A cox proportional hazards regression will be used to examine the association between the primary exposure variables and the risk of the first exacerbation, up to 5 years of follow up from the index in GOLD A and B COPD patients. Intended public health benefit of the research: This research will better inform clinicians on identifying COPD patients with a high risk of a first exacerbation outcome and aid clinicians to know where early optimisation efforts may be best targeted.
• Number of any moderate/severe exacerbations
• Number of moderate exacerbations
• Number of severe exacerbations
• Moderate/Severe Exacerbations in 1 year follow up period
• Moderate/Severe Exacerbations in 3 year follow up period
• Moderate/Severe Exacerbations in 5 year follow up period
Kieran Rothnie - Chief Investigator - GlaxoSmithKline Services Unlimited (UK)
Beade Numbere - Corresponding Applicant - GSK
Afisi Ismaila - Collaborator - GSK
Steve Gelwicks - Collaborator - GlaxoSmithKline - USA
Yifei Lu - Collaborator - GlaxoSmithKline - UK
HES Admitted Patient Care;Patient Level Index of Multiple Deprivation