慢性阻塞性肺疾病稳定期患者六分钟步行试验诱导的运动性低氧的预测方法研究

背景运动性低氧（EID）是慢性阻塞性肺疾病（COPD）患者普遍存在的问题，与COPD患者的预后有一定相关性，目前预测EID的指标多依赖肺功能且结论不一。目的探究适合基层医疗机构预测COPD稳定期患者六分钟步行试验（6MWT）诱导的EID的方法。方法本研究为回顾性研究，选择2019—2020年于中日友好医院呼吸内科门诊进行随访的COPD稳定期患者67例，同时完善了肺功能、6MWT、评估改良英国医学研究学会呼吸困难指数（mMRC）、慢性阻塞性肺病评估测试（CAT），并计算BODE指数。收集6MWT过程中最低血氧饱和度与试验开始时的静息血氧饱和度的差值（ΔSpO2），以ΔSpO2≥4%为EID判定标准。评估ΔSpO2与mMRC评分、CAT评分及BODE指数的关系，绘制mMRC评分、CAT评分及BODE指数预测COPD稳定期患者发生EID的受试者工作曲线（ROC曲线）。结果6MWT中的ΔSpO2与mMRC评分（r=-0.492，P<0.001）、CAT评分（r=-0.447，P<0.001）、BODE指数（r=-0.415，P<0.001）均呈负相关。mMRC评分、CAT评分及BODE指数预测COPD稳定期患者发生EID的ROC曲线下面积分别为0.683、0.765、0.711，最佳截断值分别为2分、14分、2分。结论mMRC评分、CAT评分及BODE指数均可作为基层医疗机构预测COPD稳定期患者发生EID的方法。

Prediction Methods of Exercise Induced Desaturation Detected by Six-minute Walk Test in Patients with Stable Chronic Obstructive Pulmonary Disease

Background Exercise-induced desaturation(EID)is highly prevalent,and associated with the prognosis in patients with chronic obstructive pulmonary disease(COPD).Current predicators of EID mostly depend on pulmonary function,and the assessment for their values is different.Objective To explore simple,and accurate methods suitably used in primary care to predict EID by six-minute walk test(6MWT)in patients with stable COPD.Methods A retrospective study was conducted.Participants were 67 stable COPD patients with respiratory clinic follow-ups selected from China-Japan Friendship Hospital from 2019 to 2020.Data were collected,including assessment results of pulmonary function test,6MWT,modified Medical Research Council(mMRC),and COPD Assessment Test(CAT),as well as calculated BODE index.EID in 6MWT was defined as the difference between minimum oxygen saturation in 6MWT and resting oxygen saturation at the beginning of 6MWT(ΔSpO₂)≥4%.mMRC score,CAT score and BODE index were compared between patients with and without EID in 6MWT to estimate the association ofΔSpO₂ in 6MWT with mMRC score,CAT score and BODE index.ROC analysis was used to estimate the predictive value of mMRC score,CAT score and BODE index for inducible hypoxia in 6MWT.Results TheΔSpO₂ in 6MWT was significantly negatively correlated with mMRC score(r=-0.492,P<0.001),CAT score(r=-0.447,P<0.001),and BODE index(r=-0.415,P<0.001).The AUC of mMRC score in predicting EID in 6MWT was 0.683(with 2 as the optimal cut-off value),and that for CAT score was 0.765(with 14 as the optimal cut-off value),for BODE index was 0.711(with 2 as the optimal cut-off value).Conclusion All of mMRC score,CAT score and BODE index can be used to predict EID in 6MWT in patients with stable COPD.