Figure 4From: Vascular endothelial growth factor: an angiogenic factor reflecting airway inflammation in healthy smokers and in patients with bronchitis type of chronic obstructive pulmonary disease?Spearman's rank correlation: VEGF and IL-8 levels in induced sputum of asymptomatic (r = 0.636, p = 0.026) and COPD smokers (r = 0.673 and p = 0.023). 4b. Spearman's rank correlation: VEGF and TNF-α levels in induced sputum of asymptomatic (r = 0.622, p = 0.031) and COPD smokers (r = 0.818 and p = 0.002).Back to article page