Division of Rehabilitation, Akita University Hospital, Akita City, Japan.
Department of Rehabilitation, Akita City Hospital, Akita City, Japan.
Clin Respir J. 2022 Aug;16(8):572-580. doi: 10.1111/crj.13528. Epub 2022 Jul 22.
Skeletal muscle dysfunction is one of the major extrapulmonary complications of chronic obstructive pulmonary disease (COPD). Some studies have reported a relationship between physical activity (PA) level and skeletal muscle quality assessed by echo-intensity (EI) in healthy individuals but not in patients with COPD.
The aim of this study is to investigate the relationships between PA level and both skeletal muscle EI and skeletal muscle mass in patients with COPD.
We employed a cross-sectional design. Forty male outpatients with stable COPD were enrolled. Using B-mode ultrasonography, we measured the rectus femoris muscle cross-sectional area (RF-CSA) and EI (RF-EI). The RF-CSA and RF-EI were measured on frozen images using an electronic caliper and 8-bit gray-scale analysis, respectively. The objective PA level was determined by monitoring daily step counts and moderate-to-vigorous physical activity time (MVPA) with an activity monitor. A general regression model was used to assess the relationships between PA level and both RF-CSA and RF-EI. Age and body mass index (BMI) were adopted as confounding variables.
Twenty-five outpatients with stable COPD (age, 70 ± 7 years old; forced expiratory volume in 1 s, 55.0 ± 24.9% of predicted values) were finally enrolled in the present study. Even after adjusting for age and BMI, the daily step counts and MVPA were significantly associated with RF-EI, and knee extensor force was associated with RF-CSA.
The present study showed that PA level was associated with RF-EI in patients with COPD. In addition, RF-CSA was associated with knee extensor force. When assessing skeletal muscle using ultrasonography in patients with COPD, we should also assess EI.
骨骼肌功能障碍是慢性阻塞性肺疾病（COPD）的主要肺外并发症之一。一些研究报告称，在健康人群中，体力活动（PA）水平与回声强度（EI）评估的骨骼肌质量之间存在关系，但在 COPD 患者中并非如此。
本研究旨在探讨 COPD 患者 PA 水平与骨骼肌 EI 和骨骼肌质量之间的关系。
我们采用了横断面设计。纳入了 40 名稳定期 COPD 的男性门诊患者。使用 B 型超声，我们测量了股直肌横截面积（RF-CSA）和 EI（RF-EI）。使用电子卡尺和 8 位灰度分析分别在冻结图像上测量 RF-CSA 和 RF-EI。通过使用活动监测器监测日常步数和中等到剧烈体力活动时间（MVPA）来确定客观的 PA 水平。使用一般回归模型评估 PA 水平与 RF-CSA 和 RF-EI 之间的关系。年龄和体重指数（BMI）被用作混杂变量。
最终有 25 名稳定期 COPD 门诊患者（年龄 70 ± 7 岁；1 秒用力呼气量占预计值的 55.0 ± 24.9%）纳入本研究。即使在调整了年龄和 BMI 后，日常步数和 MVPA 与 RF-EI 显著相关，膝关节伸肌力量与 RF-CSA 相关。
本研究表明，PA 水平与 COPD 患者的 RF-EI 相关。此外，RF-CSA 与膝关节伸肌力量相关。在使用超声评估 COPD 患者的骨骼肌时，我们还应该评估 EI。
