A Pilot Study of the Cancer Distress Coach-Caregiver App: A Digital Intervention for Reducing PTSD Symptoms in HCT...

Caregivers of hematopoietic cell transplantation (HCT) survivors face high risk for posttraumatic stress disorder (PTSD) but lack psychosocial support. Digital health tools may offer scalable solutions to address caregiver distress. This pilot study evaluated the feasibility, acceptability, and preliminary efficacy of Cancer Distress Coach-Caregiver (CaDC-C), an app designed to reduce PTSD symptoms in cancer caregivers.

This report focuses on the first-stage intervention of a larger Sequential Multiple Assignment Randomized Trial (SMART). Participants were initially randomized to receive CaDC-C or Usual Care (i.e., offered psychosocial services available at their respective institutions). Assessments were conducted at baseline and Week 4, and those with no meaningful symptom improvement at Week 4 were re-randomized to higher-intensity interventions. While details about the second-stage randomization will be reported separately, here we report on acceptability of CaDC-C use at Week 14.

Forty-four caregivers consented to participate, N = 36 completed Week 4 surveys (82% retention) and N = 31 completed Week 14 surveys (70% retention). Our post-intervention acceptability benchmark was achieved at Week 14 with 78.9% (n = 15) endorsing at least moderate satisfaction. Additionally, most reported CaDC-C enhanced their knowledge of PTSD and caregiving (84.2%, n = 16), explained their symptoms (78.9%, n = 15), and provided practical solutions to their problems (68.4%, n = 13). At Week 4, 81% (n = 13) reported a clinically meaningful reduction in PTSD symptoms (≥ 5 decrease in PCL-5 score). CaDC-C participants also demonstrated a significant reduction in anxiety symptoms at Week 4 (p = 0.02).

This pilot demonstrates the feasibility, acceptability, and preliminary efficacy of CaDC-C as a first-line intervention for PTSD symptoms in cancer caregivers. Future research should evaluate outcomes from higher-intensity interventions and determine the efficacy of CaDC-C in larger, more diverse samples.