SWEmean of Quadriceps a Potential Index of evaluation of clinical features of COPD

A study was conducted to develop a potential quadriceps' index of complication evaluation for patients with chronic obstructive pulmonary disease (COPD) which is simple, convenient, and quantifiable.

They conducted a prospective study of 59 patients with COPD and 56 healthy controls recruited by the Chengdu First People's Hospital. Grayscale ultrasound (US) of the rectus femoris was performed to measure the thickness (RFthick) and cross-sectional area (RFcsa). Shear wave elastography was used to determine the mean elasticity index (SWEmean) of the rectus femoris (SWERFmean), vastus lateralis (SWEVLmean) and vastus medialis (SWEVMmean). Clinical features included dyspnea index score (modified British Medical Research Council (MMRC) score), COPD Assessment Test (CAT), the Five-Repetition Sit-to-Stand Test (5STS) and the Six-Minute Walk Test (6MWT). We compared the differences between US parameters and SWEmean in healthy controls and COPD patients. We also described the correlation between US parameters, SWEmean and clinical features of patients with COPD.

Results:

• The intra-observer repeatability for the performance of using SWE to measure quadriceps stiffness was excellent
• There was a statistically significant difference in the SWEmean of the quadriceps but no significant difference in terms of RFthic and RFcsa between healthy controls and COPD patients.
• The SWERFmean was positively correlated with the 6MWT and negatively related to the mMRC, CAT and 5STS
• However, the RFthic, RFcsa, SWEVLmean and SWEVMmean were not correlated with clinical features

Thus, as a supplement to US, SWE reflects changes of stiffness in the quadriceps of COPD patients and can expand the dimension of US for assessing the quadriceps. Furthermore, SWEmean was associated with clinical features and represents a potential index with which to reflect the clinical features of COPD patients.

Reference:

Niu Y, Yue Y, Zheng Y, Long C, Li Q, Chen Y, Chen Z, Ma X. SWEmean of Quadriceps, a Potential Index of Complication Evaluation to Patients with Chronic Obstructive Pulmonary Disease. Int J Chron Obstruct Pulmon Dis. 2022;17:1921-1928 https://doi.org/10.2147/COPD.S374945