Chronic Obstructive Pulmonary Disease (COPD) is a progressive lung disease. COPD medications were tested in randomised trials, and evidence from these trials informs COPD treatment guidelines. Unfortunately, trials have strict eligibility rules meaning many people with COPD who would need to be prescribed these drugs by their GP could not have been included. For instance, people aged over 80 years and people with many illnesses as well as COPD. Treatment decisions for these patients are therefore based on evidence obtained in randomised trials of very different types of patients. This project will measure COPD treatment effects in patient groups excluded from a landmark COPD medication trial (TORCH), to help make better recommendations about their treatment.
We will use information routinely collected during GP and hospital appointments to assess the impact that different COPD treatments have on pneumonia, COPD flare ups, and death. Comparison treatments are long-acting beta-agonists, long acting muscarinic antagonists, and inhaled corticosteroids. First we will see how well COPD treatments work when prescribed to people that are similar to those included in a large COPD randomised trial. Then we will see how well the treatments work when prescribed to patient groups excluded from this trial.
We will use CPRD data linked with HES to select patients with COPD. We will then validate the use of CPRD data for estimating COPD treatment effects by replicating findings of the landmark COPD trial called TORCH. Using individual patient data from TORCH, we will assemble a cohort in the CPRD with similar characteristics to TORCH participants and test whether observational data can generate comparable results to trials, using cohort methodology with propensity score techniques to adjust for potential confounding. Next we will use the methodological template we have developed to determine risks and benefits of COPD treatments in people excluded from TORCH. Outcomes are pneumonia, COPD exacerbation, mortality and time to treatment change. Groups to be studied include the elderly (>80 years), people with substantial comorbidity, people with and without underlying cardiovascular disease and people with mild COPD.
Comparisons will be made according to COPD treatment status for; rate of COPD exacerbation, pneumonia and mortality over 3 years. For exacerbations, a negative binomial model will be used, with the number of exacerbations as the outcome and the log of treated time as an offset variable. Time to mortality and first pneumonia will be analysed using Cox proportional hazards regression.
COPD exacerbation, to be defined using our previously developed algorithm (Rothnie et al, 2016)
All cause mortality, as recorded in ONS mortality statistics
Pneumonia, as defined using an algorithm published previously by our group (Millet et al, 2013)
Time to COPD treatment change, determined by prescribing records indicating the start of a new, additional COPD treatment
Ian Douglas - Chief Investigator - London School of Hygiene & Tropical Medicine ( LSHTM )
Kevin Wing - Corresponding Applicant - London School of Hygiene & Tropical Medicine ( LSHTM )
Elizabeth Williamson - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
Jennifer Quint - Collaborator - Imperial College London
John Tazare - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
Rhea Fitzgerald - Collaborator - London School of Hygiene & Tropical Medicine ( LSHTM )
Sebastian Schneeweiss - Collaborator - Brigham & Women's Hospital
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation