A new study published in Nicotine & Tobacco Research found that those using e cigarettes alone were more than twice as likely to develop COPD than people who didn't use any tobacco products, A Whirlwind Tour of E Cigarettes and Vaping Health Professional Webinar Smoking Status and COPD Symptoms and Prognosis Journal of the COPD Foundation Full article: Health impact of e cigarettes and heated tobacco products in chronic obstructive pulmonary disease: current and emerging evidence Exclusive e cigarette use raises COPD risk but not type 2 diabetes or heart failure risk