Validation of real-life asthma research endpoints (Real-life asthma endpoint validation)

Study type

• Study topic:
  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Assessment of risk minimisation measure implementation or effectiveness

  Disease epidemiology

  Drug utilisation

  Effectiveness study (incl. comparative)
• Data collection methods:
  Secondary data collection

Non-interventional study

• Non-interventional study design:
  Other
• Non-interventional study design, other:
  Validation study

Study drug and medical condition

• Medical condition to be studied:
  Asthma

Population studied

• Short description of the study population:
  Patients within the OPCRD dataset who:; (i) Either start, step-up or change maintenance ICS asthma therapy at an index prescription date (IPD) (i.e. the IPD for each eligible patient is the date at which they initiated, stepped-up or changed therapy); (ii) Have ≥2 continuous years’ practice data, including ≥1 year before the index prescription date and ≥1 year after the index prescription date; (iii) Have an asthma diagnostic code and/or receive ≥2 respiratory prescriptions in the year before IPD (baseline year) and ≥2 respiratory prescription in the year after IPD (outcome year) (i.e. ≥1 in addition to that prescribed at IPD); (iv) Aged 5–60 years
• 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:
  66500

Study design details

• Main study objective:
  To validate a series of objective asthma control measures that have been used in published real-life respiratory research. The outcome measures will be compared and contrasted to patient-reported outcomes and/or gold-standard, validated asthma control tools and measures (as appropriate).
• Outcomes:
  • Risk Domain Asthma Control (RDAC): database composite measure• Overall control: RDAC+limited symptom relief • Severe exacerbation (composite based on ATS/ERS definition)• Clinical definition of exacerbation (extended version of 3)• Mediation possession ratio • Treatment success: RDAC + no use of additional therapy• Asthma/respiratory-related in patient admissions• Oral Thrush
• Data analysis plan:
  Where possible, and relevant, endpoints will be assessed in terms oftheir:• Validity: a measure of their clinical relevance, the extent to whichthey reflect the clinical reality of interest. Comparison against RCT tools will use ordinal logistic regression (univariate analysis) and binomial logistic regression (multivariate analyses). ROC curve analysis will aid identification of appropriate thresholds• Responsiveness: the extent to which they respond to appropriate(defined as guideline-recommended) treatment. NB: an endpoint can be valid without being responsive. Stats test: McNemar Test• “Predictiveness”: the extent to which the measure is associatedwith risk of future asthma exacerbations. NB: not all endpoints would not be expected to (nor will be) predictive of future exacerbation risk. Analysis approach: multivariate analysis.Exploratory Analysis: Investigate internal consistency ofcomposite variables:o GINA Controlo RDACo OAC.

Documents

Study publications

Colice G, Chisholm A, Dima AL, Reddel HK, Burden A, Martin RJ, Brusselle G, Pop…