A nationwide study of breast cancer, depression, and multimorbidity among hospitalized women and men in the United States.

Breast cancer patient depression rates were higher than the general inpatient population with a strong gradient effect between increasing numbers of comorbidities and the odds of depression. Comorbidities, including mental health-related, negatively impact breast cancer prognosis, increasing cancer-specific mortality as well as mortality for other conditions. Unplanned hospitalization episodes in a patient with breast cancer can be noted as an opportunity for mental health screening and intervention.