Longitudinal dyadic associations of fear of cancer recurrence and the impact of treatment in prostate cancer patients and their spouses

Background: Fear of cancer recurrence (FCR) in patients and their spouses is associated with reduced quality of life, but little is known about longitudinal dyadic associations of FCR between them. This study examined (i) the trajectory of FCR from pre-treatment to 12 months later; (ii) dyadic associations of FCR over time; and (iii) whether cancer treatment type predicted later FCR among prostate cancer patients and their spouses.Methods: Sixty-nine patients and 71 spouses of patients with localized prostate cancer completed a FCR measure at baseline (pre-treatment), 6 months and 12 months later (post-treatment). A repeated measures linear mixed model was used to examine FCR trajectories. Actor-partner interdependence models (APIMs) were conducted on the 52 couples with complete data to examine actor and partner effects and treatment type on subsequent FCR.Results: Patients and spouses reported moderate FCR levels over time, though spouses' FCR was significantly higher than patients' FCR (p<.001). FCR declined significantly for both groups over time (p<.001). APIMs demonstrated significant actor effects in baseline to 6 month, and 6-12 month models. Surgery was significantly associated with lower spouse FCR at 6 months, and radiation with lower patient FCR at 12 months.Conclusions: This is the first study to have concurrently examined FCR longitudinally in prostate cancer patients and spouses. Patients' and spouses' FCR declined from pre- to post-treatment, with spouses experiencing greater FCR than patients over time. FCR in patients and spouses did not appear to impact one another over time. Treatment type impacted FCR in patients and spouses differently.