CCL18 and chronic obstructive pulmonary disease: Higher levels of PARC (also known as CCL18) have been previously associated with an increased risk of death in patients with a range of chronic diseases, including chronic obstructive pulmonary disease, (Sin et al., 2011) idiopathic pulmonary fibrosis, (Prasse et al., 2009) coronary artery disease, (de Jager et al., 2012) and cancer progression.