关键词: 肺疾病, 慢性阻塞性；6 min步行试验；简易躯体能力测试试验；改良英国医学研究学会呼吸困难指数

Abstract: Background　Elderly patients are more easily to be found with chronic obstructive pulmonary disease （COPD），as well as its associated sarcopenia and decreased exercise capacity. Exercise capacity has an association with the prognosis，but there is little research on the evaluation methods of the two. Objective　To explore simple and accurate methods that can assess the exercise capacity and prognosis of patients with COPD in the community. Methods　A total of 100 patients with stable COPD were recruited from China-Japan Friendship Hospital from January 2018 to December 2019. The relationships of six-minute walking distance（6MWD） with Short Physical Performance Battery（SPPB） score and modified British Medical Research Council（mMRC） classification were analyzed. Results　The result of 6MWD increased with the decrease of mMRC score for classifying COPD （rs=-0.431，P=0.002）. The AUC of mMRC classification for predicting 6MWD was 0.749 （P<0.001），and the maximum Youden index was 0.426 when 6MWD was 483.5 meters，which was determined as the cut-off threshold. The SPPB was positively correlated with the intragroup data（P<0.001），and its correlation with 5-repetition sit-to-stand（5STS）was the strongest（rs=0.751）. Therefore，6MWD was correlated with 5STS（rs=0.291，P=0.038）. Conclusion　Both mMRC classification and 5STS test could be used as simple methods with relatively high accuracy for the assessment of exercise capacity and prognosis of patients with COPD in primary care，and they are partially correlated. When the 6MWD is less than 483.5 meters，dyspnea restricts movement greatly，and pulmonary rehabilitation can be carried out timely.

Key words: Pulmonary diseases, chronic obstructive；Six minutes walk test；Short physical performance battery；Modified British medical research council