ENLIGHTEN: Assessment of quality improvement in the International Severe Asthma Registry

Study type

• Study topic:
  Other
• Study topic, other:
  Investigation of data quality and clinical practice over time in patients with severe asthma
• Study type:
  Non-interventional study
• Scope of the study:
  Validation of study variables (exposure outcome covariate)
• Data collection methods:
  Primary data collection

Non-interventional study

• Non-interventional study design:
  Cohort

Population studied

• Short description of the study population:
  This study uses data on eligible patients with severe asthma contributing to the ISAR programme from those countries that have consented for their data to be used for research.
• Age groups:
  Adults (18 to < 65 years)

  Adults (18 to < 46 years)

  Adults (46 to < 65 years)
• Special population of interest:
  Other
• Special population of interest, other:
  People living with severe asthma
• Estimated number of subjects:
  95568

Study design details

• Study design:
  Prospective cohort study using the International Severe Asthma Registry (ISAR)
• Main study objective:
  To investigate data quality (completeness) and clinical practice (long-term oral corticosteroid use and severity of asthma when starting biologics) over time in the International Severe Asthma Registry;
• Setting:
  This is a prospective cohort study using the International Severe Asthma Registry, a global collaborative initiative to gather anonymous, longitudinal, real-life data for patients with severe asthma. ISAR provides a rich source of data for studies of symptoms, treatments and patient outcomes in people with asthma. A consistent goal of the ISAR is to improve data quality, which involves constant re-evaluation of existing data and how it might be enhanced.
• Comparators:
  N/A
• Outcomes:
  (1) Patients meeting 90% and 100% data quality standards; (2) Completeness of variables in ISAR; (3) Long-term oral corticosteroid use; (4) Biologic initiation
• Data analysis plan:
  The analysis will use a combination of joinpoint regression (log-linear model and the weighted Bayesian Information Criterion (BIC) test with a parametric method), interrupted time-series approaches (creation of splines at fixed timepoints when changes are expected to occur) and time-to-event analyses (Kaplan-Meier and flexible parametric approaches) to evaluate differential time in discontinuing/reducing LTOCS by calendar year and asthma severity indicators and initiating biologics by calendar year.
• Summary results:
  Findings from this study will be presented at the Respiratory Effectiveness Group (REG) ; in March 2025. A report will be finalised by December 2025 and the work will be submitted to a peer-reviewed journal in December 2026.