Alterations and interdependence in self-reported sleep-wake parameters of patient–caregiver dyads during adjuvant chemotherapy for breast cancer

Purpose/Objectives: To longitudinally explore changes, similarities, differences, and interrelations in the sleep-wake parameters of patient–caregiver dyads throughout adjuvant chemotherapy for breast cancer. Design: Observational, repeated-measures, dyadic study. Setting: Four ambulatory oncology clinics in Scotland. Sample: 48 dyads consisting of patients and their primary informal caregivers. Methods: Four dyadic, self-reported sleep-wake assessments took place before chemo-therapy (T0), during chemotherapy cycles 1 (T1) and 4 (T2), and after chemotherapy (T3). Dyads completed the Pittsburgh Sleep Quality Index. Multilevel hierarchical linear modeling was used to explore dyadic data. Main Research Variables: Perceived sleep quality, sleep onset latency (SOL), total sleep time, habitual sleep efficiency, wake after sleep onset, daily disturbance, daytime napping duration, overall sleep-wake impairment. Findings: The majority of dyads had at least one poor sleeper throughout the study; 25%–35% were dyads of concurrent poor sleepers. Curvilinear patterns of change were evident for patients’ (but not caregivers’) sleep-wake parameters, steadily deteriorating from pre- to midtreatment, then leveling off close to baseline. Average trajectories were significantly different between the dyad members but indicative of a trend for concurrent deterioration at T2. Dyad members’ perceived sleep quality, SOL, and overall sleep-wake impairment were closely interrelated; wake variables remained uncoupled. Conclusions: Despite overall differences in magnitude, sleep problems may be concurrently present in both dyad members, covary, and peak midway through chemotherapy. Implications for Nursing: Dyadic sleep assessments can shed light on potential areas of sleep interaction to enable interventions to support care dyads at risk of sleep distress during chemotherapy for breast cancer