Predictors of the trajectories of self-reported sleep disturbance in men with prostate cancer during and following radiation therapy

Study Objectives: To examine how self-reported ratings of sleep disturbance changed from the time of the simulation visit to four months after the completion of radiation therapy (RT) and to investigate whether specific patient, disease, and symptom characteristics predicted the initial levels of sleep disturbance and/or characteristics of the trajectories of sleep disturbance. Design: Prospective longitudinal study. Setting: Two radiation therapy centers. Patients: Patients (n = 82) who underwent primary or adjuvant RT for prostate cancer. Measurements and Results: Changes in self-reported sleep disturbance were measured using the General Sleep Disturbance Scale (GSDS). Depressive symptoms were assessed using the Center for Epidemiologic Studies-Depression Scale. Trait and state anxiety were measured using the Spielberger State-Trait Anxiety Inventory. Hierarchical linear modeling was used to answer the study aims. Self-reported sleep disturbance increased during the course of RT and then decreased following the completion of RT. Predictors of higher levels of sleep disturbance included younger age, higher levels of trait anxiety, higher levels of depressive symptoms, and higher levels of sleep disturbance at the initiation of RT. Conclusions: Sleep disturbance is a significant problem in patients with prostate cancer who undergo RT. Younger men with co-occurring depression and anxiety may be at greatest risk for sleep disturbance during RT.