Chronic obstructive pulmonary disease (COPD) is a common, preventable, and treatable condition of the lungs. Patients with COPD experience various symptoms including shortness of breath, coughing and wheezing.
There are a wide range of drugs that are available for the treatment of COPD in the UK, some of which are used as needed to manage a short-term worsening of symptoms (termed “short-acting”) and others which are used daily to prevent symptoms over an extended period of time (termed “long-acting maintenance”). Long-acting maintenance therapies can be prescribed as a single inhaled drug, or, to help prevent “flare-ups” in symptoms (called exacerbations), patients are usually given inhaler treatments which contain a combination of two or three types of drugs (termed “dual” and “triple” therapy, respectively), taken together as part of a single inhaler.
This study aims to describe the extent to which patients take their long-acting maintenance therapy as they should be taken, a concept known as adherence, and how often patients stop taking their long-acting maintenance therapy to switch to other types of treatment, a concept known as persistence. Moreover, this study also aims to describe adherence to long-acting maintenance therapy prescribed prior to a ‘step up’ in treatment to triple therapy (inhaler combinations of three different drugs given to patients with the most severe of symptoms).
Aim: To assess medication adherence and persistence to long-acting maintenance therapies for COPD in UK clinical practice. This evidence will assist physicians in making more informed decisions regarding long-acting maintenance therapy with the aim of improving patients’ outcomes.
Objectives: To describe i) medication adherence (binary), ii) medication adherence (continuous) and iii) persistence, among COPD patients newly initiating long-acting maintenance therapy by therapy regimen. Adherence to long-acting maintenance therapies immediately prior to triple therapy initiation will also be described. We will also describe patient characteristics (including baseline healthcare resource use [HCRU] and direct medical costs) and explore the relationship between adherence and both moderate-severe COPD exacerbations and rescue medication use.
Primary exposure: Long-acting maintenance therapy, i.e. LAMA monotherapy, ICS/LABA dual therapy (open/fixed), LAMA/LABA dual therapy (open/fixed), single inhaler triple therapy (SITT) and multiple inhaler triple therapy (MITT).
Outcomes: Medication adherence, persistence, exacerbations, rescue medication use, HCRU/costs.
Methods: A retrospective cohort study of COPD patients newly initiating long-acting maintenance therapy between Nov-2017 and Mar-2020 (indexing period), using linked primary and secondary care data through the Clinical Practice Research Datalink (CPRD) Aurum database and Hospital Episode Statistics (HES) Admitted Patient Care (APC), Outpatient (OP) and Accident and Emergency (A&E) datasets, respectively. The first/earliest treatment prescription date (by regimen and daily dose) during the index period will determine the index date (patients may have multiple index dates). A minimum of 12 months pre-index data and 6 months follow-up are required for study inclusion.
Data analysis: Proportion of days covered (PDC) will determine medication adherence; PDC<80% representing non-adherent, PDC≥80% adherent, and as a continuous measure. Persistence will be assessed using Kaplan-Meier survival analysis with median time-to-non-persistence reported, where reached. Medication adherence and persistence will be calculated at class/regimen level for the primary analysis, i.e. within-class switches will contribute to adherence and persistence estimates.
Adherence to long-acting maintenance therapy as a categorical variable (using PDC); Adherence to long-acting maintenance therapy as a continuous variable (using PDC); Persistence to long-acting maintenance therapy; Exacerbations (moderate-to-severe, moderate, and severe); Rescue medication prescriptions; Treatments prescribed prior to initiating long-acting maintenance therapy; Healthcare resource utilisation (all cause and COPD-related); Direct medical costs (all-cause and COPD-related)
Kieran Rothnie - Chief Investigator - GlaxoSmithKline Services Unlimited (UK)
Robert Wood - Corresponding Applicant - Adelphi Real World
Afisi Ismaila - Collaborator - GSK
Beade Numbere - Collaborator - GSK
Christina Diomatari - Collaborator - Adelphi Real World
Mitchell Lucas - Collaborator - Adelphi Real World
Monica Seif - Collaborator - Adelphi Real World
Olivia Massey - Collaborator - Adelphi Real World
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;Patient Level Index of Multiple Deprivation