Zhou Zijing, Zhou Aiyuan, Zhao Yiyang, Duan Jiaxi, Chen Ping
Department of Respiratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China.
Research Unit of Respiratory Disease, Central South University, Changsha, China.
Int J Chron Obstruct Pulmon Dis. 2018 May 24;13:1675-1682. doi: 10.2147/COPD.S161225. eCollection 2018.
Both the COPD Assessment Test (CAT) and the Clinical COPD Questionnaire (CCQ) were recommended as comprehensive symptom measures by the Global Initiative for Chronic Obstructive Lung disease. The main objective of this work was to compare the evaluation of symptom severity with the CAT and the CCQ and find a cutoff value of the CCQ for the Chinese clinical population.
Patients diagnosed with stable COPD in the outpatient department who completed the CAT and CCQ were enrolled from November 2015 to December 2016. Scores of 0-10, 11-20, 21-30, and 31-40 represent low, medium, high, and very high impact level, respectively, by CAT. Scores of the CCQ can be considered as acceptable (CCQ<1), acceptable for moderate disease (1≤CCQ<2), instable-severe limited (2≤CCQ<3), and very instable-very severe limited (CCQ≥3).
According to the CAT, only 20.4% of patients belonged to the high (21≤CAT≤30) and very high (31≤CAT≤40) impact levels, which were statistically lower than those of the CCQ, which classified over half of the population (51.1%) into the instable-severe limited (2≤CCQ<3) and very instable-very severe limited (CCQ≥3) categories (<0.001). The kappa of agreement for the symptom groups by CAT and CCQ (cutoff point 1.5) was 0.495, but only slight agreement (0.144) was found between the CAT and CCQ with the cutoff point of 1.0. The CAT and the total CCQ had a strong correlation (rho=0.776, <0.01). The CCQ 1.0 and 1.5 corresponded to CAT 4.2 and 9.7, respectively. The CAT 10.0 was equivalent to 1.53 of the CCQ. In addition, with higher scores of the CAT and CCQ, subjects displayed more impairment in lung function, higher levels on modified Medical Research Council, and higher exacerbation rates in the last year (<0.001). Similarly, patients with more exacerbations presented worse scores on the CAT and total CCQ as well as its 3 domains (<0.001).
Compared with the CAT, the CCQ was more likely to classify the patients into more severe categories, and 1.5 might be a better cutoff point for the CCQ than 1.0. Both the CAT and the overall CCQ with its 3 domains were able to discriminate between groups of patients that differ in COPD severity.
慢性阻塞性肺疾病全球倡议组织推荐慢性阻塞性肺疾病评估测试（CAT）和临床慢性阻塞性肺疾病问卷（CCQ）作为综合症状测量工具。这项研究的主要目的是比较CAT和CCQ对症状严重程度的评估，并找出中国临床人群中CCQ的临界值。
选取2015年11月至2016年12月在门诊诊断为稳定期慢性阻塞性肺疾病且完成CAT和CCQ的患者。CAT评分0 - 10、11 - 20、21 - 30和31 - 40分别代表低、中、高和非常高的影响水平。CCQ评分可分为可接受（CCQ<1）、中度疾病可接受（1≤CCQ<2）、不稳定 - 重度受限（2≤CCQ<3）和非常不稳定 - 非常重度受限（CCQ≥3）。
根据CAT，只有20.4%的患者属于高（21≤CAT≤30）和非常高（31≤CAT≤40）影响水平，这在统计学上低于CCQ，CCQ将超过一半的人群（51.1%）分类为不稳定 - 重度受限（2≤CCQ<3）和非常不稳定 - 非常重度受限（CCQ≥3）类别（<0.001）。CAT和CCQ（临界值1.5）对症状组的一致性kappa值为0.495，但临界值为1.0时，CAT和CCQ之间仅存在轻微一致性（0.144）。CAT与CCQ总分具有强相关性（rho = 0.776，<0.01）。CCQ的1.0和1.5分别对应CAT的4.2和9.7。CAT的10.0等同于CCQ的1.53。此外，随着CAT和CCQ评分升高，受试者肺功能损害更严重，改良医学研究委员会分级更高，且过去一年急性加重率更高（<0.001）。同样，急性加重次数更多的患者在CAT、CCQ总分及其三个领域的得分也更差（<0.001）。
与CAT相比，CCQ更倾向于将患者分类为更严重的类别，对于CCQ而言，1.5可能是比1.0更好的临界值。CAT以及包含三个领域的CCQ总分均能够区分慢性阻塞性肺疾病严重程度不同的患者组。
