The relationship between health-related quality of life, lung function and daily symptoms in patients with persistent asthma

It is generally believed that there is a direct correlation between asthma control and a patient's health-related quality of life (HRQL). Objective and subjective measures of asthma control are used interchangeably. A retrospective analysis from 8994 patients from 27 randomized, controlled clinical trials with persistent asthma was conducted to determine the degree of association which exists between objective (lung function) and subjective (symptoms, quality of life) measures. Assessments were made via forced expiratory volume in 1-second (FEV 1), self-reported symptoms and the Asthma Quality of Life Questionnaire (AQLQ) overall scores. Baseline percent predicted FEV 1 was weakly correlated with baseline symptom-free days (SFD) and baseline overall AQLQ scores ( r=0.11 and 0.09, respectively; P