Clinically stable emphysematous COPD patients exhibit low leptin levels compared with the chronic bronchitis subtype.159 During acute flare ups, these plasma levels rise temporarily,189 as seen in NSCLC.209, 210 Likewise, enhanced plasma ghrelin levels are noticed in COPD211 and NSCLC212 and are related to cachectic status. Here, LEP is linked to chronic obstructive pulmonary disease.