Cancer Type and Risk of Newly Diagnosed Depression Among Elderly Medicare Beneficiaries With Incident Breast, Colorectal, and Prostate Cancers.

BACKGROUND

Elderly individuals (age >65 years) with cancer are at high risk for newly diagnosed depression after a cancer diagnosis. It is not known whether the risk of newly diagnosed depression varies by cancer type.

PURPOSE

To examine the variations in the risk of newly diagnosed depression by cancer type among elderly individuals with cancer.

METHODS

This study used a retrospective cohort study design and data from the linked SEER-Medicare files. Elderly individuals (age >65 years) with incident breast, colorectal (CRC), and prostate cancers diagnosed between 2007 and 2011 (N=53,821) were followed for 12 months after cancer diagnosis. Depression diagnosis was identified during the 12-month follow-up period after cancer diagnosis using the ICD-9-Clinical Modification. Complementary log-log regression was used to examine the association between cancer type and risk of newly diagnosed depression after adjusting for other risk factors for depression.

RESULTS

We found a significantly higher percentage of newly diagnosed depression among women with CRC compared with those with breast cancer (5.8% vs 3.9%), and among men with CRC compared with those with prostate cancer (3.4% vs 1.6%). In the adjusted analysis, women with CRC had a 28.0% higher risk of newly diagnosed depression compared with women with breast cancer (adjusted risk ratio [ARR], 1.28; 95% CI, 1.12-1.46) and men with CRC had a 104.0% higher risk of newly diagnosed depression compared with those with prostate cancer (ARR, 2.04; 95% CI, 1.65-2.51).

CONCLUSIONS

Our findings identified cancer types associated with a high risk of newly diagnosed depression after cancer diagnosis, who might benefit from routine depression screening to help in its early detection and treatment.