Chronic obstructive pulmonary disease, called COPD for short, is a common disease that affects the lungs and causes breathlessness, cough, and phlegm. Many patients with COPD experience sustained periods of worsened symptoms, that are described as exacerbations. These exacerbations can lead to a spiral of further worsening symptoms and increase the risk of death. It is therefore desirable to find out who is at increased risk of experiencing an exacerbation of COPD so that there are more opportunities to prevent them. In this study we seek to understand how COPD patients who have exacerbations of different frequencies and severity differ to COPD patients who do not experience frequent exacerbations. This will benefit the public by highlighting groups of people with COPD who may be at greater risk of exacerbations and ultimately who may be eligible for new treatments.
In this study we aim to understand the clinical outcomes and healthcare resource utilisation (HCU) of chronic obstructive pulmonary disease (COPD) patients. We will use CPRD Aurum linked with patient-level IMD, HES APC, and ONS mortality data. The population will be patients aged ≥40 years with a validated COPD diagnosis, a smoking history, continuous registration at a GP practice, with acceptable data in the year before index, at least 1 day of follow-up prior to the outcome, and eligible for linkage to HES, IMD, and ONS. The inclusion and exclusion criteria from the BOREAS trial will be applied to the population as far as is possible using EHR data. We will use a cohort study design to investigate FEV1 decline, healthcare utilisation (HCU), mortality, and time to long-term oxygen therapy (LTOT), Major adverse cardiovascular events (MACE), next moderate exacerbation of COPD, and next severe exacerbation of COPD. We will also examine rates of MACE, and moderate and severe exacerbations. Cox or Poisson regression will be used for count variables, as appropriate. Mixed linear regression will be used to investigate the relationship between disease control and lung function decline over time. For HCU, fully parametric models (e.g. Weibell) will be used, as appropriate. This study will benefit public health by providing a greater understanding of factors associated with more frequent and more severe exacerbations of COPD and ultimately subgroups of COPD patients who may be eligible for new treatments.
Major adverse cardiovascular events (MACE); Moderate exacerbations of chronic obstructive pulmonary disease (COPD); Severe exacerbations of COPD; Prescription of long-term oxygen therapy (LTOT); Forced expiratory volume in 1 second (FEV1) decline; Health care utilisation (HCU); Mortality.
Jennifer Quint - Chief Investigator - Imperial College London
Philip Stone - Corresponding Applicant - Imperial College London
Siu Suen Wong - Collaborator - Imperial College London
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation