RT Journal Article SR Electronic T1 Fat-Free Mass Index for Evaluating the Nutritional Status and Disease Severity in COPD JF Respiratory Care FD American Association for Respiratory Care SP respcare.04358 DO 10.4187/respcare.04358 A1 Yuwen Luo A1 Luqian Zhou A1 Yun Li A1 Songwen Guo A1 Xiuxia Li A1 Jingjing Zheng A1 Zhe Zhu A1 Yitai Chen A1 Yuxia Huang A1 Rui Chen A1 Xin Chen YR 2016 UL http://rc.rcjournal.com/content/early/2016/01/26/respcare.04358.abstract AB BACKGROUND: Despite the high prevalence of weight loss in subjects with COPD, the 2011 COPD management guidelines do not include an index measuring nutritional status. Fat-free mass index (FFMI) can accurately determine the nutritional status of subjects and may be closely correlated with COPD severity. We aimed to determine the nutritional status evaluated by FFMI according to the 2011 Global Initiative for Chronic Obstructive Lung Disease (GOLD) levels in stable subjects with COPD and the association between nutritional status and respiratory symptoms, exercise capacity, and respiratory muscle function.METHODS: We included 235 stable subjects with COPD in this cross-sectional study. All of the subjects were divided into the 2011 GOLD Groups A, B, C, and D. FFMI (measured by bioelectrical impedance), spirometry (FEV1, percent-of-predicted FEV1, and FEV1/FVC), respiratory muscle function (peak inspiratory and peak expiratory pressures), exercise capacity (6-min walk distance), and dyspnea severity (Modified Medical Research Council dyspnea scale) were measured and compared between the GOLD groups.RESULTS: Malnutrition was identified in 48.5% of subjects and most prevalent in Group D (Group A: 41%, Group B: 41%, Group C: 31%, and Group D: 62%). FFMI was significantly lower in Group D (P < .001), with both sexes considered malnourished. Low FFMI significantly correlated with frequent exacerbation, older age, decreased pulmonary function, 6-min walk distance, peak inspiratory pressure, and worsened dyspnea. FFMI was significantly lower in the emphysema-dominant phenotype and mixed phenotype compared with the normal phenotype and airway-dominant phenotype. A stepwise multiple linear regression analysis identified peak inspiratory pressures and older age as independent predictors of FFMI.CONCLUSIONS: Malnutrition is highly prevalent in all COPD groups, particularly in Group D subjects, who warrant special attention for nutritional intervention and pulmonary rehabilitation. FFMI significantly correlated with exercise capacity, dyspnea, respiratory muscle function, and pulmonary function and may be a useful predictor of COPD severity.