Abstract
BACKGROUND: Though greater positive psychological well-being (PPWB) is associated with both improved physical and mental health in irritable bowel syndrome (IBS), it has not yet been explored as a primary target of brain-gut behavior therapies (BGBTs). Accordingly, we developed a novel, 9-week, phone-delivered BGBT to cultivate PPWB in IBS, and examined its feasibility, acceptability, and preliminary effects in a randomized waitlist-controlled proof-of-concept trial. METHODS: Twenty-two adults with IBS meeting Rome IV criteria were randomized, stratified by gender and IBS subtype, to the intervention (n = 12) or waitlist-control (WLC; n = 10) groups. Participants completed specific positive psychology (PP) activities and phone sessions weekly with an interventionist. Intervention feasibility was assessed by the proportion of completed sessions, and acceptability by weekly ease/utility ratings. Exploratory psychological and health-related self-report measures were collected pre- and post-intervention. KEY RESULTS: Participants (N = 22; ages 19-79; 55% female) completed 85% of sessions, above our a priori feasibility threshold of 65%. The intervention was rated as easy to complete (mean = 7.2/10, 95% CI: [6.70, 7.75]) and subjectively helpful (mean = 7.6/10, 95% CI: [7.14, 8.01]). Of the 18 participants who completed the intervention, 11 (61%) no longer met criteria for IBS post-intervention. Compared to the WLC, the intervention led to promising but nonsignificant improvements in exploratory clinical outcomes including IBS symptom severity, IBS health-related quality of life, and resilience, with effect sizes ranging from 0.1 to 0.7. CONCLUSIONS AND INFERENCES: This 9-week, phone-delivered intervention targeting greater PPWB in IBS was feasible, well-accepted, and associated with promising improvements in key IBS-related outcomes, highlighting the need for further testing.