Airways obstruction, chronic expectoration, and rapid decline of FEV1 in smokers are associated with increased levels of sputum neutrophils.

Airways obstruction and chronic expectoration, as well as accelerated decline in lung function, are associated with increased numbers of neutrophils in the sputum of smokers and ex-smokers which suggests that neutrophilic inflammation of the airways may be involved in the pathogenesis of chronic obstructive pulmonary disease.