PT  - JOURNAL ARTICLE
AU  - Shrikrishna, Dinesh
AU  - Tanner, Rebecca
AU  - Patel, Mehul
AU  - Donaldson, Anna V.J.
AU  - Smith, Cayley
AU  - Puthucheary, Zudin A.
AU  - Seymour, John M.
AU  - Sidhu, Paul S.
AU  - Hart, Nicholas
AU  - Moxham, John
AU  - Polkey, Michael I.
AU  - Hopkinson, Nicholas S.
TI  - Ultrasound measurement of quadriceps wasting in patients with GOLD stage II COPD and its relationship to physical activity
DP  - 2011 Sep 01
TA  - European Respiratory Journal
PG  - 4879
VI  - 38
IP  - Suppl 55
4099  - http://erj.ersjournals.com/content/38/Suppl_55/4879.short
4100  - http://erj.ersjournals.com/content/38/Suppl_55/4879.full
SO  - Eur Respir J2011 Sep 01; 38
AB  - Introduction: Ultrasound measurement of rectus femoris cross-sectional area (USRFCSA) is a radiation-free measure of muscle bulk that relates to quadriceps strength.1 A recent study reported that a significant proportion of GOLD stage II patients have quadriceps weakness.2 We hypothesised that quadriceps wasting, measured by USRFCSA, would be observed in GOLD stage II patients and would correlate with daily physical activity levels.Methods: USRFCSA and quadriceps maximum voluntary contraction (QMVC) were measured as described by Seymour et al 1. Physical activity was recorded for six consecutive days using a multisensor biaxial accelerometer, SenseWear Pro Armband™. Fat free mass (FFM) was estimated using bioelectrical impedance and a disease specific regression equation.Results: We studied 100 patients with stable COPD, (GOLD stage II-33%, III-34%, IV-33%), mean (SD) age 65 (9) years, 57% male and 23 age-matched healthy controls. USRFCSA was significantly reduced (517mm2 vs 626mm2; p=0.005) in Stage II patients compared to controls. USRFCSA was also significantly reduced in stage III (500mm2; p=0.0006) and IV (522mm2; p=0.007) disease. Using a stepwise regression model in all patients, FEV1% predicted and USRFCSA, but not FFM index and QMVC, correlated with daily physical activity (steps) (r2=0.4, p<0.0001).Conclusion: USRFCSA is reduced in GOLD stage II COPD and is related to daily physical activity. USRFCSA provides a bedside method for identifying quadriceps muscle loss in less severe disease and may guide the application of pulmonary rehabilitation in these patients.1. Seymour JM et al, Thorax 2009;64:418-23.2. Seymour JM et al, Eur Resp J 2010;36:81-8.