Relationship Between Daily Psychological (In)flexibility and Affect Following Hematopoietic Cell Transplantation.

OBJECTIVE: Psychological flexibility (PF; the ability to be fully present and open to experience and engage in values-based activities) and inflexibility (PI; the absence of this ability) may affect patients' emotional well-being after cancer treatment. However, understanding the impact of psychological (in)flexibility in the daily lives of cancer survivors remains limited. This study distinguished within- and between-person associations between PF and PI subprocesses and daily affect in hematopoietic cell transplantation (HCT) survivors. METHODS: Participants (N = 155; mean age 45.74 ± 12.38 years; 55.5% male; 100% Polish/White) completed daily assessments of PF subprocesses (present moment awareness, self as context, acceptance, defusion, values, committed actions), their PI counterparts, and affect (positive and negative) for 14 consecutive days after hospital discharge. Multilevel structural equation modeling was used to distinguish within- and between-person associations. RESULTS: For PF subprocesses, committed action and acceptance were associated with better affect at the within- and between-person levels, respectively. Contact with values was associated with better affect at both levels. Present-moment awareness coincided with worse emotional well-being, though this between-person association lacked robustness. The PI subprocesses of fusion, inaction, and lack of contact with the present moment demonstrated within-person associations with worse affect, though the latter two relationships were not robust. At the between-person level, fusion and lack of contact with values were associated with higher negative and lower positive affect, respectively. CONCLUSION: PF and PI subprocesses had diverse, level-specific correlates of emotional well-being in HCT survivors. These findings may help identify processes that merit further investigation as potential intervention targets.