Department of Research and Development, CIRO+, Centre of Expertise for Chronic Organ Failure, 6080 AB Haelen, Hornerheide 1, Postbus 4009, 6085 NM, Horn, The Netherlands.
NUTRIM-School of Nutrition and Translational Research in Metabolism, Maastricht, The Netherlands.
Respir Res. 2021 Mar 25;22(1):93. doi: 10.1186/s12931-021-01689-w.
Cut offs for fat-free mass index (FFMI) and appendicular skeletal muscle mass index (ASMI) are available for diagnosing low muscle mass in patients with COPD. This study aimed to investigate: (1) the frequency of low muscle mass (FFMI and ASMI) applying different cut-offs and (2) the functional translation (clinical impact) of low muscle mass, in patients with COPD stratified into BMI categories.
Patients with COPD were assessed regarding body composition, exercise capacity, quadriceps muscle strength, symptoms of anxiety and depression, dyspnea and quality of life upon referral to pulmonary rehabilitation. The proportion of patients with low muscle mass was compared among BMI categories. Clinical outcomes between patients with normal and low muscle mass within each BMI category were compared.
469 patients with COPD were included for analyses. The frequency of patients classified as low FFMI varied significantly according to the choice of cut-off (32 to 54%; P < 0.05), whereas the frequency of patients with low ASMI was 62%. When applying age-gender-BMI-specific cut-offs, 254 patients (54%) were classified as low FFMI. The choice of the cut-off affected the frequency of patients with low muscle mass in all BMI categories. Overweight and obese patients with low muscle mass were more frequently males and presented worse pulmonary function, exercise capacity and muscle strength compared with overweight and obese patients with normal muscle mass.
Approximately half of the overweight and obese patients with COPD have low muscle mass when applying age-gender-BMI-specific cut-offs. Low muscle mass is associated with worse functional outcomes in overweight and obese COPD patients.
体脂指数（FFMI）和四肢骨骼肌质量指数（ASMI）的截断值可用于诊断 COPD 患者的肌肉减少症。本研究旨在调查：（1）应用不同截断值时低肌肉量（FFMI 和 ASMI）的频率；（2）在 COPD 患者中，根据 BMI 类别分层，低肌肉量的功能转化（临床影响）。
在向肺康复转诊时，对 COPD 患者进行身体成分、运动能力、股四头肌力量、焦虑和抑郁症状、呼吸困难和生活质量评估。比较 BMI 类别中低肌肉量患者的比例。比较每个 BMI 类别中正常肌肉量和低肌肉量患者之间的临床结果。
共纳入 469 例 COPD 患者进行分析。根据截断值的选择，FFMI 低的患者比例差异显著（32%至 54%；P<0.05），而 ASMI 低的患者比例为 62%。当应用年龄性别 BMI 特异性截断值时，254 例患者（54%）被归类为低 FFMI。在所有 BMI 类别中，截断值的选择都会影响低肌肉量患者的比例。与正常肌肉量的超重和肥胖 COPD 患者相比，低肌肉量的超重和肥胖患者更多为男性，且肺功能、运动能力和肌肉力量更差。
当应用年龄性别 BMI 特异性截断值时，大约一半的超重和肥胖 COPD 患者存在低肌肉量。低肌肉量与超重和肥胖 COPD 患者的功能结局较差有关。
