Chronic obstructive pulmonary disease (COPD) is increasingly considered as a complex disease involving the participation of several organs. The hormonal, metabolic and musculoskeletal implications of the generalized process involving oxidative stress, inflammatory mediators, cytokines and endocrine hormones have only begun to be understood.The systemic effects range from cytokine-induced priming of the peripheral leukocyte, to muscle wasting induced by cytokines such as tumor necrosis factor-α. Despite a general consensus that chronic inflammation is a characteristic phenomenon of the disease, surprisingly little is known regarding the underlying pathogenic mechanisms.