Electronic cigarette use and its association with asthma, chronic obstructive pulmonary disease (COPD) and asthma COPD overlap syndrome among never cigarette smokers National Emphysema Foundation E cigarettes are Poor Substitutes for Conventional Smoking in COPD Patients Adult E Cigarettes Use Associated with a Self Reported Diagnosis of COPD Vaping and COPD: Is it okay or can it cause more problems? E cigarette use tied to increased COPD, asthma risk MDedge