Fat-free mass index for evaluating the nutritional status and disease severity in COPD

Abstract

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