Perception of Asthma Symptoms as Assessed on the Visual Analog Scale in Subjects With Asthma: A Real-Life Study

BACKGROUND: The perception of symptoms is a cornerstone in asthma management, but studies concerning this aspect provide conflicting evidence. The visual analog scale has been proposed as a useful tool for assessing perception of respiratory symptoms. The present study investigated whether visual analog scale assessment of perception of asthma symptoms was correlated to lung function or clinical features. METHODS: This cross-sectional study enrolled 388 subjects with asthma (159 males; mean age 39.7 y). Perception of asthma symptoms was assessed by the visual analog scale; lung function was measured by spirometry. Asthma control was evaluated by the asthma control test. Anxiety and depression were evaluated on the Hospital Anxiety and Depression Scale questionnaire. RESULTS: Asthma was well controlled in 46.6% of subjects. Asthma symptoms in the prior month were reported by 59% of subjects; asthma signs were detected in 7.2%. The visual analog scale score was moderately correlated to FEV1 (r = 0.43). Subjects with bronchial obstruction had lower visual analog scale values than those without (P < .001). A visual analog scale score of 6 was a reliable cutoff point to discriminate subjects with bronchial obstruction (area under the curve = 0.71 at receiver operating characteristic curve; odds ratio [ OR] = 7.58). Reported asthma symptoms (OR = 4.83), asthma signs (OR = 8.36), and anxiety (OR = 1.14) were predictive of a visual analog scale score of < 6. CONCLUSIONS: This real-life study found that assessment of asthma symptoms by the visual analog scale might be a reliable tool in managing patients with asthma.