| Popis: |
Impulse oscillometry (IOS) is regarded as a sensitive method to detect lung function impairment. Impaired IOS appears to relate better than spirometry to respiratory symptoms. However the evidence from large studies is scarce and therefore we studied if abnormal IOS relates to respiratory symptoms in individuals with normal spirometry from the SCAPIS. Normal values for postbronchodilatory IOS were defined in 3664 healthy, never-smoking individuals. Based on the upper limit of normal, we defined abnormal resistance (R) at 5 Hz (R5), at 20 Hz (R20), and area under reactance (AX). Similarly, lower limit of normal was used to define abnormal X5. We studied how abnormal IOS parameters related with respiratory symptoms in 8674 individuals, aged 50-65 years, with FEV1/VC-ratio >0.7 and FEV1>80% predicted. Higher prevalence of abnormal R5, R20, X5 and AX were found with regard to wheeze and dyspnea, analysed separately (all p-values In conclusion, abnormal IOS parameters are related with increased respiratory burden in individuals with normal spirometry. Reactance parameters appear to be stronger related to wheeze, while resistance is stronger related to dyspnea and cough. |
