Assessing meaningful change in the Asthma Impairment and Risk Questionnaire

Area of Science:

• Pulmonary Medicine
• Clinical Assessment Tools
• Asthma Management

Background:

• The Asthma Impairment and Risk Questionnaire (AIRQ) is a 10-item tool assessing asthma control, with lower scores indicating better control.
• It comprises 7 impairment items (2-week symptom recall) and 3 risk items (12-month exacerbation recall).
• A Follow-up AIRQ version uses a 3-month recall for exacerbations.

Purpose of the Study:

• To evaluate the responsiveness of the AIRQ over time.
• To identify a minimal important difference (MID) for the AIRQ.

Main Methods:

• Longitudinal data from 1070 asthma patients (≥12 years) were analyzed.
• Anchor-based methods correlated AIRQ score changes with Patient Global Impression of Change, established MIDs for other asthma tools, and exacerbation occurrence.
• AIRQ scores were assessed using 12-month recall (baseline, 12 months) and 3-month recall (3, 6, 9 months).

Main Results:

• A 'much improved' Patient Global Impression of Change correlated with AIRQ score decreases of -1.8 to -2.0.
• AIRQ changes aligned with established MIDs for the St. George's Respiratory Questionnaire and Asthma Control Test.
• A 2-point higher baseline AIRQ score increased the odds of 12-month exacerbation by 1.7 (95% CI, 1.53-1.89).

Conclusions:

• A change score of 2 is recommended as the minimal important difference (MID) for the AIRQ.
• This MID reflects meaningful clinical improvement in asthma control.
• The AIRQ demonstrates responsiveness to changes in asthma status.