Breast cancer patients and caregiver inter- and intrapersonal spillover effects on anxiety, depression, pain, and fatigue during the first year of treatment

Anxiety and fatigue are vulnerable to longitudinal interpersonal "spillover" of symptoms, particularly for caregivers, starting early in treatment. We also find in this pilot study that concurrent biobehavioral reactivity symptom spillover occurs in some form throughout the first year of breast cancer treatment. It is common for interventions that target symptoms of biobehavioral reactivity to focus on the individual patient. However, given the degree of longitudinal and concurrent spillover observed between breast cancer patients and caregivers, we recommend future research test behavioral interventions that teach dyadic coping skills in addition to replicating findings with a fully powered prospective study.