Asthma control assessed in the EGEA epidemiological survey and health-related quality of life

Abstract

Background: The aims were to assess 1) the relationship of asthma control assessed by combining epidemiological survey questions and lung function to Health-Related Quality of Life (HRQL) and 2) whether individuals with controlled asthma reach similar generic HRQL levels as individuals without asthma.

Methods: The analysis included 584 individuals without asthma and 498 with asthma who participated in the follow-up of the Epidemiological study on Genetics and Environment of Asthma (EGEA). Asthma control was assessed from survey questions and lung function, closely adapted from the 2006-2009 Global Initiative for Asthma guidelines. The Asthma Quality of Life Questionnaire (AQLQ, scores range:1-7) and the generic SF-36 (scores range: 0-100) were used.

Results: Adjusted mean total AQLQ score decreased by 0.5 points for each asthma control steps (6.4, 5.9 and 5.4 for controlled, partly-controlled and uncontrolled asthma respectively, p < 0.0001). The differences in SF-36 scores between individuals with controlled asthma and those without asthma were minor and not significant for the PCS (-1, p = 0.09), borderline significant for the MCS (-1.6, p = 0.05) and small for the 8 domains (<5.1) although statistically significant for 4 domains.

Conclusion: These results support the discriminative properties of the proposed asthma control grading system and its use in epidemiology.