Background:
Chronic lung disease such as asthma or COPD may be exacerbated by electronic nicotine device (ENDS) use. Despite this, little is known about the extent to which adults with chronic lung disease use ENDS and what factors are associated with use.

Methods:
We analyzed data from the second wave of the Population Assessment of Tobacco and Health (PATH) study. The PATH study recruited 28,362 U.S. adults over the age of 18 using a multi-stage randomized sampling protocol. Our analysis was restricted to adults who reported being treated for COPD or asthma in the past 12 months (N=1,748). Among these individuals, we examined prevalence of ever and current ENDS use, intensity of use, and motivations for use.

Results:
Approximately one-quarter (24.72%) of individuals being treated for COPD or asthma reported ever using ENDS; 4.09% were established users and 3.99% were experimental users. Established e-cigarette users were more likely to be white and younger. The average number of puffs from an e-cigarette on the last day used was 18.05. Key motivations for ENDS use among this population include: perceptions of less harm to the user (79.72%) and to other people (78.84%), because they can be used in places where people can't smoke (74.2%), perceptions that they help people quit smoking (73.94%), perceived acceptability to non-smokers than cigarettes (70.37%), and appealing flavors (64.0%).

Conclusions:
A significant number of individuals being treated for lung disease have or are currently using ENDS, and many of these individuals use these products for health-related concerns. Healthcare providers treating these patients should ask about ENDS use and offer counseling and treatment to help these individuals become tobacco free.