Impact of Pre-Diagnosed Depressive Symptoms on Treatment Choice, Delay in Initiating Treatment, and Mortality Among Women Aged ≥65 Years with Breast Cancer

Studies that have sought to describe and account for pre-diagnosed depressive symptoms on BC treatment choice, delay in initiating treatment, and mortality have been inconsistent. The purpose of the study is to examine the association between pre-diagnosed depressive symptoms and their impact on breast cancer (BC) treatment, treatment delays, and mortality. We conducted a retrospective cohort study using the Surveillance, Epidemiology, and End Results-Medicare Health Outcomes Survey (SEER-MHOS) dataset among women aged 65 years and older diagnosed with BC. Among 3840 eligible patients, 28.1% had pre-diagnosed depressive symptoms. Patients with pre-diagnosed depressive symptoms who were diagnosed with early-stage BC were significantly more likely (OR = 1.52; 95% CI: 1.26-1.84) to undergo mastectomy or receive breast-conserving surgery (BCS) alone rather than BCS plus radiation therapy (RT) compared to patients who were not pre-diagnosed with depressive symptoms. Among patients with advanced-stage BC, pre-diagnosed depressive symptoms were not significantly associated with treatment type. Among Hispanic patients, pre-diagnosed depressive symptoms were associated with treatment delays. Overall, patients with pre-diagnosed depressive symptoms had a 16% increased adjusted risk of BC-related mortality compared to those who were not pre-diagnosed with depressive symptoms, and those with advanced-stage cancer had an 18% higher adjusted risk of death than early-stage BC. Conclusions: Overlooking depressive symptoms management prior to a breast cancer diagnosis may result in poorer survival outcomes. Early detection and consistent management of depression are critical for improving patient survival.