Abstract
PURPOSE: Advances in cancer treatment have led to improved survival rates, but challenges related to health-related quality of life (HRQoL) persist, often exacerbated by sleep disturbances. We present a pre-registered, secondary analysis of HRQoL from a trial of sleep interventions among women with early or advanced breast cancer receiving chemotherapy. PATIENTS AND METHODS: This 6-week, multisite, remotely-delivered, randomized controlled trial compared Cognitive Behavioral Therapy for Insomnia (CBT-I), Bright Light Therapy (BLT), their combination (CBT-I + BLT), and an active control (Sleep Hygiene Education, SHE) on HRQoL as measured by the PROMIS-Preference score (anchors: 0 "Dead" to 1 "Full health") at baseline, mid-point (3-weeks), post-intervention (6-weeks), and follow-ups (3&6-months). Interventions involved emails and tailored therapist-assisted intervention sessions. RESULTS: 219 women receiving chemotherapy (M(age) 50.67 years) were recruited. At baseline, average HRQoL was low (0.27). CBT-I led to a significant improvement from baseline to post-intervention (b = 0.06; p = 0.012). In contrast, BLT showed no significant effects (all p ≥ 0.519). No CBT-I × BLT interaction was observed (all p ≥ 0.759). Clinically meaningful improvement (≥ MID) was observed in 71.2% of CBT-I participants. Within-group analyses from baseline to post-intervention showed the largest HRQoL improvements in CBT-I and CBT-I + BLT groups (both b = 0.14; p < 0.001); smaller gains were observed in BLT and SHE groups (b = 0.07-0.09; p ≤ 0.024). No significant changes were observed in any group at 6-month follow-up (all p ≥ 0.096). Exploratory analyses suggested benefits of BLT in patients with metastatic disease and greater insomnia severity. CONCLUSION: CBT-I was associated with clinically meaningful improvements in HRQoL during chemotherapy. These findings support the integration of CBT-I into supportive care and highlight the need for tailored approaches for patients with advanced disease or persistent insomnia symptoms. TRIAL REGISTRATION: ACTRN12620001133921.