Identification of distinct depressive symptom trajectories in women following surgery for breast cancer.

OBJECTIVE: Depressive symptoms, common in breast cancer patients, may increase, decrease, or remain stable over the course of treatment. Most longitudinal studies have reported mean symptom scores that tend to obscure interindividual heterogeneity in the symptom experience. The identification of different trajectories of depressive symptoms may help identify patients who require an intervention. This study aimed to identify distinct subgroups of breast cancer patients with different trajectories of depressive symptoms in the first six months after surgery. METHOD: Among 398 patients with breast cancer, growth mixture modeling was used to identify latent classes of patients with distinct depressive symptom profiles. These profiles were identified based on Center for Epidemiological Studies-Depression (CES-D) scale scores completed just prior to surgery, and 1, 2, 3, 4, 5, and 6 months after surgery. RESULTS: Four latent classes of breast cancer patients with distinct depressive symptom trajectories were identified: Low Decelerating (38.9%), Intermediate (45.2%), Late Accelerating (11.3%), and Parabolic (4.5%) classes. Patients in the Intermediate class were younger, on average, than those in the Low Decelerating class. The Intermediate, Late Accelerating, and Parabolic classes had higher mean baseline anxiety scores compared to the Low Decelerating class. CONCLUSIONS: Breast cancer patients experience different trajectories of depressive symptoms after surgery. Of note, over 60% of these women were classified into one of three distinct subgroups with clinically significant levels of depressive symptoms. Identification of phenotypic and genotypic predictors of these depressive symptom trajectories after cancer treatment warrants additional investigation.