However, participants with COPD showed higher IL-8 levels (p = 0.03, d = 0.87, power = 0.57, df = 24) and lower levels of IL-10 (p = 0.02; d = 1.21, power = 0.84, df = 24) compared with healthy controls. This evidence concerns the gene CXCL8 and chronic obstructive pulmonary disease.