[Risk Assessment of Acute Exacerbation in COPD Patients in the Context of Pulmonary Follow-Up Rehabilitation Based on the Prevalence and Severity of Comorbidities]. / Risikoabschätzung einer akuten Exazerbation bei COPD-Patienten im Rahmen einer pneumologischen Anschluss-Rehabilitation anhand der Prävalenz und Schwergradausprägung von Komorbiditäten.

ABSTRACT

INTRODUCTION: Acute COPD exacerbations (AECOPD) in the context of pulmonary rehabilitation (PR) are frequent and dangerous complications and, in addition to impairing quality of life, lead to an interruption of PR and jeopardize PR success. In this study, a correlation between the health status and an increased risk of AECOPD is described. The question arises whether the Charlson Comorbidity Index (CCI) or the Cumulative Illness Rating Scale (CIRS) are suitable for the preventive detection of COPD patients at risk for exacerbation in PR. PATIENTS AND METHODS: In a retrospective study, data of COPD patients who underwent PR in 2018 were analyzed with the CCI as the primary endpoint. All data were taken from the Phoenix Clinical Information System, and COPD exacerbations were recorded. The 44 patients (22 with and 22 without exacerbation during PR) required according to the sample size planning were randomly recruited from this pool of patients (using a random list for each group). CCI and CIRS were determined for all the cases included in the two groups. The primary endpoint (CCI) was evaluated by group comparison of the arithmetic means and Welch test. This was supported by further statistical measures of position and dispersion (median, quartile, standard deviation).In addition, the optimal cut-off point for discrimination in AECOPD and non-AECOPD patients was obtained via Receiver Operating Characteristic (ROC) analysis for both the CCI and the CIRS. RESULTS: Out of 244 COPD patients who underwent PR for an average of 21 days, 59 (24 %) suffered AECOPD that required treatment during PR. The 22 patients with AECOPD had a mean CCI of 6.77 (SD 1.97) and the 22 patients without AECOPD had a mean CCI of 4.32 (SD 1.17). This difference of -2.45 was statistically significant at a level of significance of 5 % (p < 0.001; 95 % CI [-3.45; -1.46]). The ROC analysis led to 6 as the optimal cut-off point for the CCI, with 81.8 % sensitivity for determining an AECOPD and 86.4 % specificity with an area under the curve (AUC) value of 0.87. The optimal cut-off point for CIRS was 19 with a sensitivity of 50 %, a specificity of 77.2 % and an AUC of 0.65. CONCLUSION: COPD patients with acute exacerbation during PR have a higher CCI. The CCI allows the risk of AECOPD to be assessed with high sensitivity and specificity in participants with COPD in an inpatient PR program.