Well-being in IBS: Strengths and Happiness (WISH) 2.0

The purpose of this study is to examine the feasibility, acceptability, preliminary efficacy, and candidate gut-brain mechanisms of an optimized positive psychology (PP) intervention for patients with irritable bowel syndrome (IBS), entitled "WISH," compared to an educational control intervention.

Irritable bowel syndrome (IBS), a disorder of gut-brain interaction (DGBI; also known as functional gastrointestinal (GI) disorder) is characterized by abdominal pain and altered bowel habits, and conceptualized as resulting from complex interactions between biological, psychological, and social factors. Compared to healthy populations, individuals with IBS have reduced positive psychological well-being, which in turn has been associated with impaired physical health, greater depression and anxiety, and worse health-related quality of life. A growing body of evidence supports the use of behavioral health interventions, referred to as brain-gut behavior therapies (BGBTs), as part of a comprehensive treatment approach for IBS. There is a critical need for new BGBTs for IBS that are scalable, acceptable, and mechanistically targeted.

Positive psychology (PP) interventions have successfully been implemented in a variety of other chronic medical conditions to improve well-being, health-related quality of life, health behavior engagement, and health outcomes. PP interventions are typically highly acceptable and easily delivered remotely without extensive specialized training, which increases their scalability and reach. Aside from the investigator's preliminary proof-of-concept work, however, PP interventions have not been evaluated in IBS.

Accordingly, the purpose of this study is to examine the feasibility, acceptability, preliminary eﬃcacy, and candidate gut-brain mechanisms of an optimized, 9-week, phone-delivered, PP intervention for patients with IBS, entitled "Well-being in IBS: Strengths and Happiness (WISH)," compared to a time-and attention-matched educational control intervention.

The primary aims of this randomized controlled trial (RCT) are to determine feasibility (at least 50% of participants completing at least 6/9 PP sessions) and acceptability (mean ease and utility ratings for each session of at least 7/10).

The exploratory aims of this RCT are to examine: (1) preliminary eﬃcacy of the PP intervention in improving health-related (IBS symptom severity, health-related quality of life, and IBS diagnostic criteria), psychological (positive affect, optimism, resilience, self-eﬃcacy, depression, anxiety, GI symptom-specific anxiety, response to pain, and perceived stress), and health behavior (physical activity, avoidant/restrictive eating) outcomes; and (2) candidate gut-brain mechanisms of the PP intervention including changes in autonomic function (as measured by heart-rate variability), interoception, and stress-mediated gene expression.

Eligibility Criteria:
Inclusion Criteria:

* IBS Diagnosis: Adult patients with an IBS diagnosis meeting standardized Rome IV diagnostic criteria.
* Language and communication: English fluency and access to a phone.

Exclusion Criteria:

* Severe psychiatric illness: Current manic episode, psychosis, or active substance use disorder diagnosed via the Mini International Neuropsychiatric Interview (MINI).
* Cognitive impairment: Assessed using a six-item cognitive screen developed for research.
* Plans to start or participate in another new behavioral health intervention or psychotherapy during the study period.