Baseline predictors of treatment response in the bounce back mind-body resiliency trial for AYA cancer survivors.

12101 Background: Mind-body interventions hold promise for improving coping and reducing psychological distress among adolescent and young adult (AYA) cancer survivors, yet benefits vary across participants. Little research has identified which survivors stand to benefit most from these programs. This secondary analysis of a randomized controlled trial of a mind-body group intervention tested whether baseline emotion regulation-related factors (worry and intolerance of uncertainty) moderated intervention effects on coping and distress (anxiety and depression). Methods: AYA cancer survivors (N = 72; ages 18–39) were randomized 1:1 to an 8-week virtual mind-body resiliency program (Bounce Back) or waitlist control. Primary outcomes were PROMIS anxiety and depression scores and total Measure of Current Status (MOCS) coping score at post-intervention (approximately 3-month follow-up), along with coping self-efficacy. Linear regression models, adjusted for baseline levels of each outcome, tested Randomization Group × Moderator interaction terms for two baseline moderators examined separately: Penn State Worry Questionnaire (PSWQ) and Intolerance of Uncertainty Scale (IUS). Interactions with p < 0.05 were considered evidence of moderation. Results: Compared to waitlist, participants assigned to Bounce Back showed greater improvements in anxiety and coping outcomes but similar depression outcomes overall. Randomization group differences in post-intervention anxiety were significantly moderated by both worry and intolerance of uncertainty. The intervention–control difference in anxiety (adjusted for baseline) was larger among participants reporting higher baseline worry (interaction β = −0.39, p = 0.033) and higher baseline intolerance of uncertainty (β = −0.48, p = 0.033). Neither moderator significantly altered randomization group differences in depression. For coping-related outcomes, higher baseline intolerance of uncertainty strengthened the intervention effect on coping self-efficacy (interaction β = 1.92, p = 0.047), and there was a trend for greater total MOCS improvement among participants with higher baseline worry (interaction β = 0.33, p = 0.086). Conclusions: In this secondary analysis of a randomized trial, the Bounce Back mind-body resiliency program produced the largest anxiety and coping benefits for AYA cancer survivors with relatively higher baseline worry and intolerance of uncertainty, whereas depression outcomes did not vary by these baseline characteristics. These findings suggest that emotion regulation vulnerabilities such as worry and uncertainty intolerance may help identify higher-risk AYAs who are most likely to benefit from group-based mind-body stress-management interventions. Future trials should confirm these moderators and test whether triaging higher-risk AYAs to mind-body programs improves psychological outcomes.