Abstract
BACKGROUND: Fear of cancer recurrence (FCR) and sleep disturbance are common in cancer survivors. Yet, little research has examined their relationship, and even less is known about what links may exist between these variables among the intimate partners of cancer survivors. PURPOSE: This study examines the relationship between FCR and sleep disturbance in breast cancer survivors and their partners. Using daily sleep data collected at two distinct periods early in survivorship-the completion of adjuvant treatment and the first post-treatment mammogram-higher survivor and partner FCR was hypothesized to predict greater sleep disturbance. METHODS: Breast cancer survivors and intimate partners (N = 76 couples; 152 individuals) each reported sleep duration, sleep quality, sleep onset latency, and wake after sleep onset each morning of two 21-day sleep diary bursts during the first year post-diagnosis. Three validated measures formed latent FCR factors for survivors and partners, which were used to predict average daily sleep. RESULTS: Across both sleep diary bursts, survivor FCR was associated with their own reduced sleep duration, reduced sleep quality, and greater sleep onset latency. Survivor FCR was also associated with their partners' reduced sleep quality and greater sleep onset latency. Partner FCR was associated with their own reduced sleep duration, reduced sleep quality, and greater sleep onset latency. Partner FCR was also associated with survivors' reduced sleep quality. CONCLUSIONS: Findings revealed intrapersonal and interpersonal associations between FCR and sleep disturbance, addressing gaps in knowledge on FCR and an outcome with known short- and long-term implications for health and mortality.