Efficacy of Age-Adjusted Dyspnea, Eosinopenia, Consolidation, Acidemia and Atrial Fibrillation Score in Predicting Long-Term Survival in COPD-Related Persistent Hypercapnic Respiratory Failure

<b>Background and Objectives</b>: Hypercapnic respiratory failure (HRF) is a critical clinical condition commonly encountered in acute exacerbations of chronic obstructive pulmonary disease (COPD), leading to high morbidity and mortality rates. The existing scoring systems have primarily been developed for short-term mortality prediction, and their impact on long-term survival has not been sufficiently investigated. This study aims to identify the prognostic factors affecting long-term survival in patients with persistent HRF due to COPD and to evaluate the effectiveness of the Age-Adjusted DECAF (A-DECAF) score, which was created by incorporating the age variable into the existing DECAF score, in predicting long-term survival. <b>Materials and Methods</b>: This retrospective study included patients admitted to an intensive care unit from an emergency department with HRF between April 2022 and November 2023. The demographic data, comorbidities, the laboratory results, and the treatment protocols were recorded. The A-DECAF scores were calculated and analyzed using Kaplan-Meier and ROC analyses. Survival assessment was conducted with Kaplan-Meier analysis, while univariate and multivariate Cox regression analyses were performed to identify the prognostic factors. <b>Results</b>: Among 357 patients, 24.4% died within one year after discharge. The deceased patients were significantly older (<i>p</i> < 0.001) and had higher APACHE-II, DECAF, and A-DECAF scores (<i>p</i> < 0.001 for all). ROC analysis showed that the A-DECAF score had the highest sensitivity (93.1%) and accuracy (AUC = 0.813) for survival prediction. Kaplan-Meier analysis indicated lower survival rates with increasing A-DECAF scores. Cox regression identified the A-DECAF score as the strongest independent predictor (<i>p</i> < 0.001), while lung cancer (<i>p</i> = 0.044) and invasive mechanical ventilation (<i>p</i> = 0.039) also negatively impacted survival. <b>Conclusions</b>: The A-DECAF score is an effective tool for predicting long-term survival in patients with COPD and persistent HRF, particularly aiding clinical decisions regarding elderly populations. Further research is needed to validate its use in diverse patient groups.