Changes in Cycle-Ergometer Performance during Pulmonary Rehabilitation Predict COPD Exacerbation

Early diagnosis of COPD exacerbations is vital. Exacerbations are characterised by an increase in dyspnoea that could be affect physical capacity. Changes in the physical capacity of patients with COPD during pulmonary rehabilitation could provide a predictive indication regarding the occurrence of exacerbation. This was a retrospective study of forty for patients with COPD who participated in a pulmonary rehabilitation programme between January 2015 and October 2018. Patients to have experienced at least one exacerbation during their pulmonary rehabilitation programme are included. The performance variable and dyspnoea on the cycle ergometer and the treadmill were collected during the five sessions prior to the exacerbation and the three sessions following the exacerbation. Seventy exacerbations were analysed. We found a significant decrease in the performance on the cycle ergometer during the last session before exacerbation compared with previous sessions (mean difference: 74.5% (95%CI 12.6-136.5); p < 0.01). The optimal threshold value was a 17% decrease in performance compared to the previous training session. Sensitivity was 0.46 (95%CI 0.34-0.59), specificity was 0.83 (95%CI 0.72-0.91) and the area under the curve was 0.65 (95%CI 0.56-0.74) (p < 0.01). The analysis of performance data from cycle ergometer is a potentially useful method to predict the occurrence of exacerbation.