COPD and the metabolic syndrome: an intriguing association.

Chronic Obstructive Pulmonary Disease (COPD) has been recently recognized as a condition involving more than the lungs. The presence of common factors in COPD and in other chronic extra-pulmonary diseases, as well as the co-existence of these conditions in the same adult individual, supports the hypothesis of a shared pathogenetic pathway. We will here review the interplay between coexisting COPD and the metabolic syndrome (MS), based on the most updated knowledge. We will discuss this clinical condition from the definition, to the pathophysiology and to the clinical implications. Basically, MS is more likely to be present in a COPD patients, and increased levels of circulatory pro-inflammatory proteins from both the lung and adipose tissue coincide in these patients. The relative impact of the coexisting COPD and MS may depend on several factors: the presence of physical inactivity and of systemic inflammation related to a smoking habit, sedentary lifestyle, airway inflammation and obstruction, adipose tissue and inflammatory marker activation. More studies will be required to elucidate the association between COPD and MS and to formulate individualized management approaches for this specific disease phenotype.