CRP and chronic obstructive pulmonary disease: Taking into account inflammatory indicators, the studies demonstrated that OS patients had significantly higher levels of C-reactive protein (CRP), interleukin-6, percentage of peripheral neutrophils, levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), and tumor necrosis factor α (TNFα) compared to COPD-only patients [26,35,46,97,98].