A positive psychology intervention to promote health outcomes in hematopoietic stem cell transplantation: the PATH proof-of-concept trial.

Allogeneic hematopoietic stem cell transplantation (HSCT) recipients often experience deficits in positive psychological well-being (PPWB) due to intensive treatment and follow-up care. Positive psychology interventions (PPIs) that promote PPWB via deliberate and systematic exercises (e.g., writing a gratitude letter) have consistently improved PPWB in medical populations, yet have never been studied in early HSCT recovery. In this single-arm, proof-of-concept study, we assessed the feasibility and acceptability of a novel eight-session, telephone-delivered PPI in early HSCT recovery. A priori, we defined feasibility as >50% of eligible patients enrolling in the study and >50% of participants completing 5/8 sessions, and acceptability as mean ease and utility scores of weekly participant ratings of PP exercises as 7/10. Of 45 eligible patients, 25 (55.6%) enrolled, 20 (80%) completed baseline assessments, 15 (75%) started the intervention, and 12 (60%) completed the intervention and follow-up assessments. The intervention was feasible (55.6% of eligible participants enrolled; 60% of baseline assessment completers finished 5/8 sessions) and led to very small-to-medium effect-size improvements in patient-reported outcomes. A novel, eight-week, telephone-delivered PPI was feasible and acceptable in allogeneic HSCT recipients. Larger, randomized studies are needed to examine the efficacy of PPIs for improving outcomes in this population.