© 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine Background Both loss of muscle mass (ie, sarcopenia) and obesity adversely impact clinically important outcomes in patients with chronic obstructive pulmonary disease (COPD). Currently, there are only a few studies in patients with COPD with sarcopenia and concurrent obesity, termed sarcopenic obesity (SO). Objective To explore the effects of SO on exercise capacity, health status, and systemic inflammation in COPD. Design/Settings/Participants Baseline data collected from a total of 2548 participants (2000 patients with COPD, mean age (SD), 63.5 (7.1) years; and 548 controls, 54.8 (9.0) years) from ECLIPSE (Evaluation of COPD Longitudinally to Identify Predictive Surrogate Endpoints) study, a multicenter longitudinal observational study, were used. Measurements All participants were divided into 4 body composition phenotypes using bioelectrical impedance analysis: (1) normal body composition, (2) obesity, (3) sarcopenia, and (4) SO. In patients with COPD, the 6-minute walking distance, disease-specific health status, and plasma inflammatory markers were compared among the respective body composition groups. Results Patients with COPD were 3 times more likely to present with SO compared with controls without COPD (odds ratio [OR] 3.3, 95% confidence interval [CI] 2.0–5.4, P <.001). In patients with COPD, SO was related to reduced 6-minute walking distance (−28.0 m, 95% CI −45.6 to −10.4), P <.01) and to higher systemic inflammatory burden (an elevation of at least 2 inflammatory markers, OR 1.6, 95% CI 1.1–2.5, P = .028) compared with the normal body composition group after adjustments for age, sex, smoking, body mass index, and airflow limitation. Conclusions Our findings suggest that SO is associated with worse physical performance and higher systemic inflammatory burden compared with other body composition phenotypes in patients with COPD. Trial registry ClinicalTrials.gov no. NCT00292552.