Supplementary Material for: Components of the COPD assessment test associated with the exacerbation of severe COPD patients

Introduction: The Chronic Obstructive Pulmonary Disease (COPD) Assessment Test (CAT) score is widely used for evaluating the health status of patients diagnosed with COPD. The aim of this study was to identify which components of the CAT are associated with exacerbation in severe COPD patients. Methods: Using data from the Korean COPD Subgroup Study (KOCOSS), we identified 3,440 COPD patients, among which 1,027 patients are classified as having severe COPD based on spirometry results. The CAT scores on 8 items were evaluated and classified into respiratory and non-respiratory categories. We analyzed the association between CAT item scores and moderate-to-severe exacerbations during study enrollment and the following years. Results: Patients with a history of moderate-to-severe exacerbations had higher scores on non-respiratory CAT components. Longitudinal CAT scores on all items after enrollment were higher in the moderate-to-severe exacerbation group. Additionally, the frequency of severe exacerbations was associated with specific CAT components related to limited activities, confidence leaving home, sleeplessness, and energy. Conclusions: This study revealed that the non-respiratory CAT component scores were statistically significant factors for predicting the moderate-to-severe exacerbation of severe COPD patients. Non-respiratory symptoms and functional limitations should be considered in patients with severe COPD. Interventions, such as pulmonary rehabilitation, may be needed to improve patients' overall well-being and prevent exacerbations.引言：慢性阻塞性肺疾病（Chronic Obstructive Pulmonary Disease, COPD）评估测试（CAT）评分被广泛用于评估确诊COPD患者的健康状况。本研究旨在明确CAT的哪些维度与重度COPD患者的急性加重相关。 方法：本研究利用韩国COPD亚组研究（Korean COPD Subgroup Study, KOCOSS）的数据，共纳入3440例COPD患者，其中根据肺量测定结果，1027例被归类为重度COPD患者。研究对CAT评分的8个条目进行评估，并将其划分为呼吸系统与非呼吸系统两类。本研究分析了入组时及后续数年的CAT条目评分与中重度急性加重之间的关联。 结果：有中重度急性加重病史的患者，其非呼吸系统CAT维度得分更高。入组后所有条目的纵向CAT评分在中重度急性加重组中均更高。此外，重度急性加重的发生频率与特定CAT维度相关，包括活动受限、离家信心不足、失眠及精力不足。 结论：本研究表明，非呼吸系统CAT维度得分是预测重度COPD患者中重度急性加重的统计学显著因素。临床中应考虑重度COPD患者的非呼吸系统症状与功能受限情况。或许需要采取肺康复等干预措施，以改善患者的整体健康状况并预防急性加重。