Indian Journal of Allergy, Asthma and Immunology

ORIGINAL ARTICLE
Year
: 2021  |  Volume : 35  |  Issue : 1  |  Page : 22--26

Diagnostic accuracy of respiratory impedance parameters to detect airflow obstruction in adults


Sajal De 
 Department of Pulmonary Medicine, National Institute for Research in Environmental Health, Kamla Nehru Hospital Building, Gandhi Medical College Campus, Bhopal, Madhya Pradesh, India

Correspondence Address:
Dr. Sajal De
Department of Pulmonary Medicine, All Indian Institute of Medical Sciences, Raipur, Chhattisgarh
India

OBJECTIVE: The present study was aimed to evaluate the diagnostic accuracy of impedance parameters to detect airflow obstruction and the severity of airflow obstruction in adults. METHODS: The spirometry parameters (forced expiratory volume in 1 s [FEV1], forced vital capacity [FVC], FEV1/FVC, FVC3/FVC, and FEF25-75) and respiratory impedance parameters (R5, R19, R5-19, and X5) measured by forced oscillation technique of consecutive 299 adults (male: 186) were included in the present analysis. The Spearman correlation coefficient (ρ) was used to assess the correlations of impedance parameters with spirometry indices. The area under the curve (AUC) was used to assess respiratory impedance parameters' diagnostic accuracy. RESULTS: The mean age of the study population was 54.1 ± 12.3 years, and 99 individuals (33%) had airflow obstruction (FEV1/FVC < 0.70) in spirometry. All spirometry indices (% of predicted) showed a weak negative correlation with R5, R19, R5-19, and weak positive correlation with X5. The R5 >142% predicted and X5 >136% predicted had the maximum AUC (0.75) with a sensitivity of up to 56% and specificity up to 86% to identify airflow obstruction. The impedance parameters showed low concordance with the severity of airflow obstruction. CONCLUSION: Respiratory impedance parameters had insufficient sensitivity to diagnose airflow obstruction and the severity of obstruction in adults. Thus, impedance parameters cannot a substitute for spirometry in diagnosing obstructive lung function.


How to cite this article:
De S. Diagnostic accuracy of respiratory impedance parameters to detect airflow obstruction in adults.Indian J Allergy Asthma Immunol 2021;35:22-26


How to cite this URL:
De S. Diagnostic accuracy of respiratory impedance parameters to detect airflow obstruction in adults. Indian J Allergy Asthma Immunol [serial online] 2021 [cited 2022 May 24 ];35:22-26
Available from: https://www.ijaai.in/article.asp?issn=0972-6691;year=2021;volume=35;issue=1;spage=22;epage=26;aulast=De;type=0