Incident mental disorders after breast cancer: A matched population-based cohort

To assess the risk of mental disorders and contributing factors of depression in breast cancer survivors, as well as to estimate the risk of death.

A total of 20,440 women diagnosed with breast cancer between 1997 and 2017 were identified in the Utah Cancer Registry and matched to a general population of women without cancer. To assess the risk of mental disorders and death following breast cancer, hazard ratios (HRs) and 99 % confidence intervals (CI) were estimated using Cox proportional-hazards models overall, within 2, > 2 to 5, and > 5-years of follow-up.

Compared with women without cancer, breast cancer survivors had an elevated risk of depression notably within 2 years of follow-up for depression (HR 2.64, 99 %CI 2.43, 2.87), anxiety (HR 2.89, 99 %CI 2.66, 3.15), bipolar (HR 1.85, 99 %CI 1.45, 2.37), alcohol (HR 1.88, 99 %CI 1.43, 2.46), and substance-related disorders (HR 1.95, 99 %CI 1.59, 2.39). Although the risks were attenuated compared to the immediate follow-up, the burden of alcohol- and substance-disorders persisted within 5 and depression and anxiety >5 years post cancer. Breast cancer survivors diagnosed with substance-related disorders within 2 years of cancer had a 2.3-fold higher risk of death (HR 2.28, 99 % CI 1.72, 3.03) compared to those without during the same time period. Depression predictors included obesity, ≥2 comorbidities, chemotherapy, or being separated.

Compared with women without cancer, breast cancer survivors had an elevated risk of multiple mental disorders. The risk of death was notably increased among breast cancer survivors with substance-related disorders.