Systemic inflammation is present in patients with stable COPD, as demonstrated by the increase in serum levels of acute phase proteins, i.e., C-reactive protein (CRP), fibrinogen, interleukins (IL-6 and IL-8), and tumour necrosis factor α (TNF-α), as well as the increased numbers of circulating leucocytes [8]. Here, CRP is linked to chronic obstructive pulmonary disease.