Predictors of an acute COPD exacerbation (the PACE-trial) – preliminary results from the EXACT diary

<bold>Background:</bold> Acute COPD exacerbations (AE) are associated with worsening respiratory symptoms and have a negative impact on quality of life and disease progression. Predictors of an AE could assist in the diagnosis and treatment of AECOPD. Previous studies have predominantly examined the period after diagnosis of AE. Therefore, aim of the study (<ext-link>NCT04140097</ext-link>) is to identify predictors of AE development. <bold>Methods:</bold> During an inpatient pulmonary rehabilitation (PR), a total of 355 patients will be prospectively assessed during an observational phase of 3-4 weeks to analyze various parameters before the development of an AE in case of an AE. During PR, daily symptom retrieval is assessed by the EXACT diary. <bold>Results:</bold> An evaluation of the first 200 patients from February 2020 to August 2022 was performed. 20 patients were dropouts, 147 did not develop an AE(age: 66±8 yrs) and 33 experienced an AE (age:66±7 yrs). Patients with an AE had worse lung function at baseline compared to patients without AE (FEV1: 33±11 vs. 40±15 %pred, p=0.032), more lifetime AE's(11±12 vs. 5±7, p=0.002), as well as in the last 12 months (3±2 vs. 1±1, p<0.001). The EXACT total score showed significant group differences already 4 days before the clinical diagnosis of an AE (4 days before AE:38.1±10.8 pts vs. 44.2±12.0 pts, p=0.026; day of AE: 39.0±11.6 pts vs. 54.8±13.4 pts, p<0.001). <bold>Conclusion:</bold> Preliminary data show that the EXACT total score, from 4 days before an AE, may be a predictor of a possible AE.