TY - JOUR T1 - Energy expenditure and physical activity in COPD by the DLW method and an accelerometer JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00407-2020 SP - 00407-2020 AU - Hideaki Sato AU - Hidetoshi Nakamura AU - Yuki Nishida AU - Toru Shirahata AU - Sanehiro Yogi AU - Tomoe Akagami AU - Machika Soma AU - Kaiji Inoue AU - Mamoru Niitsu AU - Tomohiko Mio AU - Tatsuyuki Miyashita AU - Makoto Nagata AU - Satoshi Nakae AU - Yosuke Yamada AU - Shigeho Tanaka AU - Fuminori Katsukawa Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/early/2021/03/18/23120541.00407-2020.abstract N2 - Although weight loss suggests poor prognosis of COPD, only a few studies have examined total energy expenditure (TEE) or physical activity level (PAL) using the doubly labeled water (DLW) method. We evaluated TEE and PAL using the DLW method together with a triaxial accelerometer to elucidate the relationships between TEE, PAL and clinical parameters leading to a practical means of monitoring COPD physical status.This study evaluated 50- to 79-year-old male patients with mild to very severe COPD (n=28) or at risk for COPD (n=8). TEE, activity energy expenditure for 2 weeks, and basal metabolic rate were measured by DLW, an accelerometer, and indirect calorimetry, respectively. All patients underwent pulmonary function, chest-computed tomography, 6-min walk, body composition and grip strength (GS) tests. Relationships between indices of energy expenditure and clinical parameters were analysed. Bland-Altman analysis was used to examine the agreement of TEE and PAL between the DLW method and the accelerometer.TEE and PAL using DLW in the total population were 2273±445 kcal·day−1 and 1.80±0.20, respectively. TEE by DLW was correlated well with that from the accelerometer and GS (p<0.0001), and PAL by DLW correlated well with that from the accelerometer (p<0.0001), GS and 6-min walking distance (p<0.001) among various clinical parameters. The accelerometer, however, underestimated TEE (215±241 kcal·day−1) and PAL (0.18±0.16), with proportional biases in both indices.TEE and PAL can be estimated by the accelerometer in patients with COPD if systematic errors and relevant clinical factors such as muscle strength and exercise capacity are accounted for.FootnotesThis manuscript has recently been accepted for publication in the ERJ Open Research. It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJOR online. Please open or download the PDF to view this article.Conflict of interest: Dr. Sato has nothing to disclose.Conflict of interest: Dr. Nakamura reports grants from Japan Agency for Medical Research and Development (AMED), during the conduct of the study.Conflict of interest: Mr. Nishida has nothing to disclose.Conflict of interest: Dr. Shirahata has nothing to disclose.Conflict of interest: Dr. Yogi has nothing to disclose.Conflict of interest: Dr. Akagami has nothing to disclose.Conflict of interest: Dr. Soma has nothing to disclose.Conflict of interest: Dr. Inoue has nothing to disclose.Conflict of interest: Dr. Niitsu has nothing to disclose.Conflict of interest: Dr. Mio has nothing to disclose.Conflict of interest: Dr. Miyashita has nothing to disclose.Conflict of interest: Dr. Nagata has nothing to disclose.Conflict of interest: Dr. Nakae has nothing to disclose.Conflict of interest: Dr. Yamada has nothing to disclose.Conflict of interest: Dr. Tanaka reports grants from Japan Agency for Medical Research and Development (AMED) , during the conduct of the study.Conflict of interest: Dr. Katsukawa reports grants from Japan Agency for Medical Research and Development (AMED), during the conduct of the study. ER -