Identifying Factors Influencing Alcohol Use after Bariatric Surgery: An Ecological Momentary Assessment - Bariatric surgery is the most effective weight loss treatment for patients who are severely obese; however, 1 in 5 patients develop an alcohol use disorder (AUD) after undergoing surgery. After surgery, changes in metabolism, hormone levels, and behaviors alter the rewarding effects of alcohol while concurrently changing its absorption rate, putting patients at significantly elevated risk of hazardous drinking. To better understand the development of AUDs after bariatric surgery, we must first identify factors leading to re-initiation of alcohol use and escalation to heavy drinking. Promising areas include mood and eating behaviors. The purpose of the proposed study is to identify the distal and proximal factors that contribute to re-initiation and episodic alcohol use following bariatric surgery. We will use an exploratory sequential mixed methods approach and first obtain qualitative data to inform the quantitative phase. In the qualitative phase, we will conduct interviews of patients who are between 6 months and 3-years post-bariatric surgery (N= 30) to identify the reasons they consumed alcohol after bariatric surgery. We will also inquire about the frequency, amount, and the antecedents and consequences of episodic alcohol use (i.e., mood, eating behaviors). This information will be used to inform the quantitative data phase (i.e., finalize the constructs to assess, how and when to measure these variables, and the frequency of assessment). In the quantitative phase, patients (N= 100) will also be recruited between 6 months and 3-years post-surgery. Participants will complete measures of substance use, mood, and eating behaviors at baseline and at 6- and 12-weeks post-baseline to capture longer-term data to identify distal factors associated with alcohol use. Within the 12-week study period, participants will also be randomly assigned a 3-week period in which they will complete an ecological momentary assessment (EMA) design. The EMA design consists of brief, daily morning and evening assessments in “real-time” regarding emotions and behaviors (i.e., substance use, affect, and eating behaviors), which will allow us to identify the factors contributing to episodic alcohol use (i.e., proximal factors). We will also examine intended and unintended drinking. Our long-term goal is to better understand the progression from re-initiation of alcohol use, to heavy use, to development of an AUD, which will assist in targeting interventions to prevent AUDs. In addition to being the first study to examine distal and proximal factors of post-surgical alcohol use, this project contains multiple innovative components including an EMA design which allows for the examination of unintended drinking. Further, given participants will have varying histories of alcohol use prior to surgery, we will explore whether distal and proximal predictors are differentially predictive of drinking among those with and without a history of heavy drinking prior to surgery. The proposed line of research is significant and relevant to NIH’s mission because it will lead to tailored, effective interventions to reduce alcohol use and prevent the development of an alcohol use disorder among patients at high risk (i.e., those who undergo bariatric surgery).