探讨对非卧床杜氏肌营养不良症(DMD)患儿采取皮质类固醇(CS)治疗≥1年的肺功能和运动功能指标变化。

选择2020年4月至2021年5月四川大学华西第二医院、成都市妇女儿童中心医院和新疆医科大学第一附属医院儿内科门诊收治的采取CS治疗≥1年的32例DMD患儿为研究对象。根据患儿采取CS初治时年龄，将其分别纳入≤7岁组(n＝13)与>7岁组(n＝19)。对这32例患儿初治后进行为期2年的回顾性纵向研究，初治与初治后第1、2年(分别采用T0、T1、T2表示)时，使用肺功能测试仪评估2组患儿4项肺功能指标[用力肺活量占预计值百分比(FVC%)、第1秒用力呼气量占预计值百分比(FEV1%)、第1秒用力呼气量与用力肺活量的比值(FEV1/FVC)、呼气峰流速占预计值百分比(PEF%)]，并采用《北极星移动评价量表》(NSAA)和3项关键运动功能指标计时测试(完成仰卧-站立、10 m走/跑和上4级楼梯各测试1次所需时间)，评估患儿运动功能。所有DMD患儿与≤7岁组、>7岁组患儿不同时间点的4项肺功能指标、NSAA评分和3项关键运动功能指标比较，采用重复测量资料的方差分析或Friedman检验。采用多重线性回归分析方法，分析DMD患儿NSAA评分及3项关键运动功能指标对FVC%的影响。本研究遵循的程序符合四川大学华西第二医院伦理委员会规定，并获得该伦理委员会批准[审批文号：科研伦审2023(303)号]。

①32例DMD患儿T0、T1、T2时，肺功能指标FVC%、FEV1%和FEV1/FVC分别总体比较，差异均无统计学意义(P>0.05)，而PEF%呈增高趋势，总体比较，差异有统计学意义(F＝4.40、P＝0.016)。进一步两两比较结果显示，T1时，FVC%较T0时增加8.3%，差异有统计学意义(Z＝－2.09、P＝0.036)；T2时，FEV1%、PEF%较T0时分别增加8.2%、9.2%，差异均有统计学意义(Z＝－2.15、P＝0.032，t＝－2.69、P＝0.011)。②T0、T1、T2时，32例DMD患儿NSAA评分呈下降趋势，而完成仰卧-站立、10 m走/跑测试所需时间，则呈增加趋势，分别总体比较，差异均有统计学意义(F＝4.33、P＝0.017，χ²＝32.32、P<0.001，χ²＝6.74、P＝0.034)。③多重线性回归分析结果显示，DMD患儿初治时，NSAA评分为影响FVC%上升的独立保护因素(b＝0.817，P＝0.027)。④T0、T1、T2时，≤7岁组DMD患儿FVC%、FEV1%、PEF%均呈上升趋势，分别总体比较，差异亦均有统计学意义(F＝10.87、12.24、11.03，P＝0.004、0.003、0.003)；完成仰卧-站立测试所需时间总体比较，差异有统计学意义(χ²＝15.17、P＝0.001)。⑤T0、T1、T2时，>7岁组DMD患儿FVC%、FEV1%、FEV1/FVC、PEF%分别总体比较，差异均无统计学意义(P>0.05)；NSAA评分呈下降趋势，完成仰卧-站立与10 m走/跑测试所需时间均呈增加趋势，分别总体比较，差异均有统计学意义(χ²＝6.50、20.99、10.11，P＝0.039、<0.001，＝0.006)。

在采取CS治疗的非卧床DMD患儿中，初治年龄≤7岁者的肺功能，在初治后2年内均呈上升趋势，而初治年龄>7岁者，在初治后2年内保持稳定；在初治年龄≤7岁与>7岁者中，运动功能均呈下降趋势，并且在初治年龄>7岁者中下降更为明显。非卧床DMD患儿的NSAA评分与其肺功能具有相关性。

To explore the changes of pulmonary and motor function indexes in children with ambulatory Duchenne muscular dystrophy (DMD) treated with corticosteroids (CS) for at least one year.

A total of 32 DMD children admitted to the outpatient department of West China Second University Hospital of Sichuan University, Chengdu Women′s and Children′s Central Hospital, and the First Affiliated Hospital of Xinjiang Medical University from April 2020 to May 2021 were selected into this study. According to the age of children when they initially received treatment with CS, they were divided into ≤7 years group (n=13) and >7 years group (n=19). A 2-year retrospective longitudinal study of these 32 children was conducted after initial treatment. And the children′s pulmonary function [forced vital capacity percent predicted value (FVC%), forced expiratory volume in one second percent predicted value (FEV1%), ratio of forced expiratory volume in one second to forced vital capacity (FEV1/FVC), peak expiratory flow percent predicted value (PEF%)] was assessed by spirometry at initial treatment and at 1 and 2 years after initial treatment (recorded as T0, T1 and T2, respectively). The North Star Ambulatory Assessment (NSAA) score and three key monitor function indexes timing tests (the time required to complete supine-up, 10 m walk/run, and climb 4 stairs test once each) were performed to evaluate the children′s motor function at T0, T1 and T2. Repeated measures analysis of variance or Friedman test was used to compare the 4 pulmonary function indexes and NSAA score and three key monitor function indexes of all DMD children, ≤7 years group and >7 years group at different time points. Multiple linear regression analysis was used to analyze the effect of NSAA score and three key monitor function indexes on FVC% among 32 DMD children. This study was approved by the Medical Ethics Committee of West China Second University Hospital, Sichuan University (Ethics No. 2023-303).

① Among the 32 DMD children, there were no significant differences in FVC%, FEV1% and FEV1/FVC at T0, T1 and T2 (P>0.05), while the PEF% showed a upward trend, and the difference was statistically significant (F=4.40, P=0.016). Further pairwise comparison showed that FVC% at T1 was 8.3% higher than that at T0, and the difference was statistically significant (Z=-2.09, P=0.036), FEV1% and PEF% at T2 was 8.2% and 9.2% higher than these at T0, and both the differences were statistically significant (Z=-2.15, P=0.032; t=-2.69, P=0.011). ② At T0, T1, and T2, the NSAA score of 32 DMD children showed a downward trend, while the time required to complete supine-up and 10 m walk/run tests showed an increasing trend, and the differences were statistically significant (F=4.33, P=0.017; χ²=32.32, P<0.001; χ²=6.74, P=0.034). ③ Results of multiple linear regression analysis showed that NSAA score at T0 was an independent protective factor for the increase of FVC% in DMD children (b=0.817, P=0.027). ④ In ≤7 years group, FVC%, FEV1%, and PEF% showed an upward trend at T0, T1, and T2, and the differences were statistically significant (F=10.87, 12.24, 11.03; P=0.004, 0.003, 0.003). The time required to complete supine-up test at T0, T1, and T2 was also statistically significant (χ²=15.17, P=0.001). ⑤ In >7 years group, there were no statistically significant differences in FVC%, FEV1%, FEV1/FVC, and PEF% at T0, T1, and T2 (P>0.05). While the NSAA score at T0, T1 and T2 showed a downward trend, and the time required to complete supine-up and 10 m walk/run tests at T0, T1 and T2 showed an increasing trend, and all the differences were statistically significant (χ²=6.50, P=0.039; χ²=20.99, P<0.001; χ²=10.11, P=0.006).

Among children with ambulatory DMD treated with CS, the pulmonary function of those with initial treatment ≤ 7 years show an upward trend within 2 years after initial treatment, but remain stable within 2 years after the initial treatment for those with initial treatment > 7 years. The motor function of children with initial treatment ≤ 7 years and > 7 years all show a downward trend, and the decline is more obvious in children with initial treatment > 7 years. There is a correlation between NSAA score and pulmonary function in ambulatory DMD children.