Survey of condensed exhaled air with an enzyme immunoassay kit in COPD patients, has revealed high level of IL6 in those patients in comparison with normal non-smokers.3 Another study on the induced sputum of COPD patients suggests that elevated levels of IL6, IL8 and tumor necrosing factor alpha (TNFa) in such patients are correlated with pathogenesis and progression of COPD.4 In other research, raised IL6 level is connected with fatigue of healthy people, especially athletes.5 This result can be extended to severe dyspnea and exhaustion of COPD patients. Here, TNF is linked to chronic obstructive pulmonary disease.