RT Journal Article SR Electronic T1 Symmetric Projection Attractor Reconstruction: Analysis of waveform morphology predicts COPD exacerbations JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP 3645 DO 10.1183/13993003.congress-2022.3645 VO 60 IS suppl 66 A1 Serna Pascual, M A1 D'Cruz, R A1 Huang, Y A1 Aston, P A1 Jolley, C A1 Rafferty, G A1 Steier, J A1 Nandi, M YR 2022 UL https://publications.ersnet.org//content/60/suppl_66/3645.abstract AB Background: Respiratory pattern analysis is currently reduced to simplified biomarkers, such as rate. However, respiratory waveforms are complex and generally sampled with high fidelity. Our novel mathematical method, Symmetric Projection Attractor Reconstruction (SPAR) analyses the morphology and variability of such waveforms, without discarding any data.Aims and objectives: To investigate whether SPAR can detect changes in respiratory waveforms that better predict impending COPD exacerbations.Methods: Retrospective nasal pressure data, recorded during resting tidal breathing, were analysed from 10 COPD patients who were home monitored daily following hospital discharge, after an exacerbation.Results: Over the 30 days of monitoring 4 patients re-exacerbated and 6 remained stable. SPAR transformations highlighted differences in waveform morphology between these two patient groups (Fig. 1). Statistically, SPAR measures outperformed respiratory rate in discriminating between groups at hospital discharge (ROC AUC 0.95 vs. 0.90) and throughout the monitoring period (ROC AUC 0.98 vs. 0.83).Conclusions: SPAR provided supplementary, early evidence identifying patients who re-exacerbated. We predict that a combination of SPAR plus conventional measures may support clinical decision making at hospital discharge and during community monitoring, providing an earlier alert for patients, carers and clinical teams.FootnotesCite this article as Eur Respir J 2022; 60: Suppl. 66, 3645.This article was presented at the 2022 ERS International Congress, in session “-”.This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).