新加坡成人慢性呼吸系统疾病患者6分钟步行距离的最小临床重要差异值研究（英文）

Minimal Clinically Important Difference for 6-Minute Walk Distance in Singaporean Adults with Chronic Respiratory Diseases

目的:6 min步行距离(6MWD)是临床上常见的功能性运动能力测试,特别是对于慢性呼吸系统疾病患者。一些文献记载了关于白种人的6MWD的最小临床重要差异(MCID),但对亚洲人群的相关信息未见记载。本研究旨在建立亚洲成人慢性呼吸道疾病患者6MWD的最小临床重要差异。方法:采用"锚定"法和"分布"法对新加坡中央医院肺康复计划登记处的资料进行了分析。"锚定"法收集确诊为慢性呼吸道疾病的患者50例,其中男38例,女12例;平均年龄(64.2±12.3)岁,通过电话采访及使用整体变化评估量表(GROC)评价患者肺康复计划后的自觉改善程度,再将患者在肺康复计划中6MWD的改变数值与相对应的患者自觉改善程度进行比较,这种关系用操作特征曲线(ROC)统计表示。通过"分布"法确定6MWD的MCID,从门诊和住院的肺康复计划(PRP)参与者中检索医疗记录136例,其中男103例,女33例;平均年龄(60.1±14.1)岁。结果 :ROC曲线表明6MWD出现临床显著性变化的最佳临界值为17.4 m,其对应的敏感性为79.4%,特异性为81.3%,阳性似然比为4.23。由"分布"法确定6MWD的最小临床重要差异值为18.6 m。结论:18.6 m为新加坡华人6MWD的最小临床重要差异的估计值。

Objective: The 6-minute walk distance(6MWD) is a common measure of functional exercise capacity in clinical populations, particularly in patients with chronic respiratory diseases. While some literature has documented the minimal clinically important difference(MCID) of the 6MWD in the Caucasian population, information on the Asian population is scanty. This study aimed to establish the MCID of the 6MWD in Asian adults with chronic respiratory diseases(CRDs). Methods: Data from the 'Pulmonary Rehabilitation Programme Registry, Singapore General Hospital ' were analysed. Both the ' anchor-based ' and ' distribution-based 'methods were used to estimate the MCID of the 6MWD. Fifty participants(38 males and 12 females) with a mean age of 64.2 years(SD 12.3) diagnosed with CRDs involved in the 'anchor-based ' method for determination of MCID of 6MWD. These participants were interviewed by telephone and rated their perceived change of improvement after pulmonary rehabilitation program using the Global Rating of Change(GROC) scale; the change in 6MWD before and after the program in these patients were compared with their perceived improvement and such relation is illustrated by the receiver operating characteristic curve(ROC). To determine the MCID of6 MWD by the 'distribution-based' method, medical records of participants from the outpatient and inpatient pulmonary rehabilitation program(PRP) were retrieved from 136 patients(103 males and 33 females), mean age of 60.1 years(SD 14.1). Results: This study showed that the ROC curve indicated an optimal cut-off value for clinically significant change in the 6MWD was 17.4 metres. This corresponded to a sensitivity of 79.4%, and specificity of 81.3%, positive likelihood ratio is 4.23. The MCID of 6MWD determined by the distribution-based estimation was 18.6 metres. Conclusion: The more conservative value of 18.6 metres is considered to be the appropriate MCID estimate for 6MWD for Chinese people with CRDs in Singapore.