Effects of E-cigarettes (ECIGs) on Pulmonary Inflammation and Behavior in HIV Infected Smokers

15 subjects will receive ECIGs and 5 control subjects will continue to smoke their chosen usual brand of combustible cigarettes (UB). Each group will receive either ECIG or UB for a total of 4 weeks and undergo pulmonary and behavioral assessments during this period. A mobile contingency management (mCM) procedure will be used to provide monetary reinforcement for biochemically verified abstinence from combustible cigarettes. Participants in the UB group will also undergo mCM procedures, but contingencies will differ. After 4 weeks, the ECIG group will be allowed to transition back to their chosen combustible cigarette product for an additional 2 weeks with additional pulmonary and behavioral assessments. All subjects will undergo three respiratory assessments in the DCRU.

"mCM procedures are a novel smoking cessation tool previously used in the field by our colleagues in the Beckham research group. This equipment is part of a procedure called mobile contingency management or mCM. The participant will use a study smartphone to record his/her CO levels and moods at random times of the day and to verify his/her cigarette usage. The mCM program will reward the participant for each CO level and data transmitted to the study team. The study team will provide detailed information and training to allow them to participate in this part of the study."

"The usual brand of cigarettes is the control group in this study. 5 participants will be allowed to continue using their usual brand of combustible cigarette in this arm of the study."