Beck Depression Inventory as a Predictor of Long-term Outcome Among Patients Admitted to the Breast Cancer Diagnosis Unit: A 25-year Cohort Study in Finland

Aim: The Beck Depression Inventory (BDI) is one of the most widely used instruments for measuring the severity of depression. However, there has been no prospective study to investigate the long-term outcome in patients admitted to Breast Cancer Diagnosis Units. Patients and Methods: In the Kuopio Breast Cancer Study, women with breast symptoms were evaluated for total BDI score before any diagnostic procedures were carried out. The relapse-free survival (RFS) was calculated from the time of diagnosis to the time of first relapse including local relapse, contralateral breast cancer (BC) or metastatic disease. The overall survival (OS) was assessed as the time from the date of diagnosis to the date of last follow-up or death of the patient. The effect of the BDI on the RFS and on the OS were calculated by the Kaplan-Meier survival analysis and the difference between the groups was assessed by the log-rank test. The RFS and OS was estimated for the study groups with a low BDI score (8) versus those with a high BDI score (< 8). The end-point of our study was to determine differences in long-term outcome and in BDI score in individuals with BC, benign breast disease (BBD) and in healthy study subjects (HSS). Results: In the Cox proportional hazard model, the total BDI score significantly predicted the 25-year RFS and OS in the HSS, BBD and BC groups combined (Hazard Ratio=1.87, p=0.039; Hazard Ratio=1.98, p=0.048, respectively), and in the Kaplan-Meier survival analysis with the log-rank test, the total BDI score predicted the 25-year RFS and OS in the HSS, BBD and BC groups combined (p=0.043; p=0.036, respectively). Conclusion: The BDI is a significant predictor of long-term outcome among patients admitted to the Breast Cancer Diagnosis Unit in Finland.