Diagnostic Potential of Oscillometry: A Population-based Approach

Rationale: Respiratory resistance (Rrs) and reactance (Xrs) measured by oscillometry and their intra-breath changes have emerged as sensitive parameters for detecting early pathological impairments during tidal breathing. Objectives: This study evaluates the prevalence and association of abnormal oscillometry parameters with respiratory symptoms and respiratory diseases in a general adult population. Methods: 7560 participants of the Austrian LEAD (Lung, hEart, sociAl, boDy) study with oscillometry measurements (Resmon Pro FULL, Restech Srl) were included in this study. The presence of respiratory symptoms and doctor-diagnosed respiratory diseases was assessed by an interview-based questionnaire. Rrs and Xrs at 5 Hz, their inspiratory and expiratory components, the area above the Xrs curve, and the presence of tidal expiratory flow limitation were analyzed. Normality ranges for oscillometry parameters were defined according to Oostveen et al. (2013). Measurements and main results: The overall prevalence of abnormal oscillometry parameters was 20%. The incidence (CI) of abnormal oscillometry increased in the presence of symptoms and/or diagnoses (17% (16 - 18%) vs 27% (25 - 29%), p<0.0001). All abnormal oscillometry parameters except Rrs at 5 Hz were significantly associated with respiratory symptoms/diseases. Significant associations were found even in subjects with normal spirometry, with abnormal oscillometry incidence rate increasing by 6% (4 - 8%, p<0.0001) in subjects with symptoms or diagnoses. Conclusions: Abnormal oscillometry parameters are present in 1/5 of this adult population and are significantly associated with respiratory symptoms and disease. Our findings underscore the potential of oscillometry as a tool for detecting and evaluating respiratory impairments, even in individuals with normal spirometry.