Women with breast cancer demonstrate increased risk for depression several years after diagnosis, according to study results.
Nis P. Suppli, MD, of the Danish Cancer Society Research Center in Copenhagen, Denmark, and colleagues used Danish national registries to obtain data on nearly 2 million women who had no diagnosis of cancer and no major psychiatric disorder.
Researchers followed the cohort from 1998 to 2011 and tracked incidence of breast cancer diagnoses. They also monitored for two outcome measures, first hospital contact for depression and redeemed prescriptions for antidepressants.
Suppli and colleagues identified 44,494 women diagnosed with breast cancer during the study period.
During the first year after diagnosis, the rate ratio for first hospital contact for depression was 1.7 (95% CI, 1.41-2.05), and the ratio remained significantly elevated after 3 years of diagnosis. The rate ratio for redemption of prescriptions for antidepressants was 3.09 (95% CI, 2.95-3.22), and the ratio remained significantly elevated 8 years after diagnosis.
Results indicated an excess absolute risk of 11 extra cases of first hospital contact for depression per 10,000 person-years in the first year after breast cancer diagnosis. Certain models showed comorbidities and positive axillary lymph nodes were associated with increased risk for hospital contact for depression.
Researchers also calculated an excess absolute risk of 430 extra cases of first use of antidepressants per 10,000 person-years in the first year post-diagnosis. Factors associated with antidepressant use included co-morbidities, node-positive disease, tumor size, older age, basic and vocational educational levels, and living alone.
Suppli and colleagues observed no clear association between type of surgery or adjuvant treatment and risk for depression.
“These results indicate that what matters with respect to risk for depression in women with breast cancer is the individual behind the tumor and the severity of her disease,” the researchers wrote.
Disclosure: The researchers report consultant or advisory roles with and honoraria from AstraZeneca and Lundbeck.