Abstract
Objective: The purpose is to examine the possibility of differentiating COPD from asthma with airflow obstruction by the method of forced oscillation of multi-frequencies technique.
Patients and Methods: Thirty-four patients with asthma (20 patients had airflow obstruction (BA with OB) and 14 patients did not (BA without OB)), 61 patients with COPD (35 patients with apparent emphysema (COPD with PE) and 26 patients without apparent emphysema (COPD without PE)), and 48 normal never-smokers were recruited, and examined pulmonary function testing including forced oscillation of multi-frequencies technique using a MostGraph-01. All COPD patients were examined a chest high-resolution computed tomography and analyzed emphysematous changes by Goddard's method and divided COPD with emphysema by emphysema score ≥6.
Results: BA without OB showed no differences from healthy non-smokers. BA with OB showed significant increases of R5, R20, R5-R20, more negative values of X5, and greater within-breath changes in R5 and R5-R20. COPD without PE showed a significant increase in R5-R20 and more negative values of X5. COPD with PE showed significant increases of R5, R5-R20, most negative values of X5, and greater within-breath changes in X5.
Conclusions: These findings suggest that a forced oscillation of multi-frequencies technique may be useful for differentiation between asthma with airflow obstruction and COPD phenotype by the manner of within-breath changes in resistance and peripheral capacitive reactance, however, not comlpeted.
- © 2014 ERS