Study type

Study topic

Disease /health condition

Study type

Non-interventional study

Scope of the study

Effectiveness study (incl. comparative)

Data collection methods

Secondary use of data
Non-interventional study

Non-interventional study design

Other

Non-interventional study design, other

Observational, historical database study, Prospectively planned comparative effectiveness study drawing on retrospective EMRs from the OPCRD
Study drug and medical condition

Medical condition to be studied

Asthma
Population studied

Short description of the study population

To be eligible for inclusion in the study, patients must meet the following criteria:
• Be aged between 2–65 years at IPD.
• Have had ≥3 wheezing episodes ever
• Have:
o Patients ≥5 years: physician-diagnosed asthma (i.e. Read code for asthma)
o Patients <5 years: ≥1 coded asthma or wheezing episode in the baseline 6 months
• Received ≥1:
o Patients ≥5 years: inhaled corticosteroid (ICS) prescription in the baseline 6 months
o Patients <5 years: asthma or wheeze prescriptions in the baseline 6 months, where a “wheeze prescription” will be a maintenance/preventer therapy (e.g. ICS, LTRA, ICS/LABA). Releiver therapies (e.g. short-acting bronchodilators) will not be classified as “wheeze prescriptions”.
• ≥38 weeks continuous records: ≥26 weeks prior to IPD (baseline 6-months) and ≥12 weeks following IPD (12-week primary outcome).
Exclusion criteria
In order to provide the fullest picture of UK primary care prescribing practice possible, few patients will be excluded. The only exclusion that will be applied will aim to avoid confusion between index and outcome events associated with asthma and those associated with other chronic comorbidities:
Patients will be excluded if they meet the following criteria:
• Are receiving chronic antibiotics for other chronic respiratory conditions (e.g. cystic fibrosis, PCD, bronchiectasis)
• Are on maintenance oral steroids (for any reason)

Age groups

Children (2 to < 12 years)
Adolescents (12 to < 18 years)
Adults (18 to < 46 years)
Adults (46 to < 65 years)

Special population of interest

Other

Special population of interest, other

Asthma patients

Estimated number of subjects

50000
Study design details

Main study objective

The aim of the proposed study is to evaluate the comparative effectiveness of managing asthma exacerbations with oral steroids alone versus combination antibiotics and oral steroids in paediatric and adult asthma populations. Secondary objectives of the study will be to explore the differential usage and associated outcomes of different classes of antibiotics, as used in this context.

Outcomes

1a. Primary care consultations coded for asthma / wheeze 1b. Primary care consultations coded for asthma / wheeze resulting in an antibiotic prescription1c. Primary care consultations coded for asthma / wheeze resulting in an oral steroid prescription1d. Primary care consultations coded for asthma / wheeze resulting in both an antibiotic and an oral steroid, 2a. Primary care consultations coded for asthma / wheeze resulting in a prescription for a short-acting bronchodilator (SABA) 2b. Consultation for asthma / wheeze resulting in a SABA2c. Hospitalisations for lower respiratory complaints2d. Accident & Emergency (A&E) / Emergency Room (ER) attendance for lower respiratory complaints.

Data analysis plan

Matching, often used to minimise potential confounding by severity, will not be possible as it would required matching on multiple events per person. Three potential options have been identified:• Approach 1: a repeated measurements analysis • Approach 2: a survival analysis considering time to event following the index event, (for all events).• Approach 3: using each patient as their own control to evaluate different time to next event for patient depending on their index prescription (e.g. comparative time to next event for each patient when prescribed oral steroids only versus oral steroids + antibiotics).
Documents
Study publications
Murray CS, Lucas SJ, Blakey J, et al. A real-life comparative effectiveness stu…