Is health-related quality of life associated with upper and lower airway inflammation in asthmatics?

Background. Allergic diseases impair health-related quality of life (HR-QoL). However, the relationship between airway inflammation and HR-QoL in patients with asthma and rhinitis has not been fully investigated. We explored whether the inflammation of upper and lower airways is associated with HR-QoL. Methods. Twenty-two mild allergic asthmatics with concomitant rhinitis (10 males, 38 ± 17 years) were recruited. The Rhinasthma was used to identify HR-QoL, and the Asthma Control Test (ACT) was used to assess asthma control. Subjects underwent lung function and exhaled nitric oxide (eNO) test, collection of exhaled breath condensate (EBC), and nasal wash. Results. The Rhinasthma Global Summary score (GS) was 25 ± 11. No relationships were found between GS and markers of nasal allergic inflammation (% eosinophils: r=0.34, P=0.24; ECP: r=0.06, P=0.87) or bronchial inflammation (pH of the EBC: r=0.12, P=0.44; bronchial NO: r=0.27, P=0.22; alveolar NO: r=0.38, P=0.10). The mean ACT score was 18. When subjects were divided into controlled (ACT ≥ 20) and uncontrolled (ACT < 20), the alveolar NO significantly correlated with GS in uncontrolled asthmatics (r=0.60, P=0.04). Conclusions. Upper and lower airways inflammation appears unrelated to HR-QoL associated with respiratory symptoms. These preliminary findings suggest that, in uncontrolled asthma, peripheral airway inflammation could be responsible for impaired HR-QoL.