Newly Developed Depression Before Breast Cancer Diagnosis Can Increase Mortality Risk

Women with newly developed depression before a breast cancer diagnosis have a significantly increased risk for death from any cause in addition to death from late-stage breast cancer, according to a study published in Cancer.

“[N]o prospective observational study with at least 2 repeated measurements of depressive symptoms and long follow-up has been performed to examine the relation between persistent depression and all-cause death or breast cancer-specific death,” Xiaoyun Liang, MD, PhD, from Beijing Normal University in China, and colleagues wrote.

“A study with this design could also determine whether the proximity of depression to the breast cancer diagnosis influences the prognosis of breast cancer patients,” Dr Liang added.

Using data from the Women’s Health Initiative (WHI), Dr Liang and colleagues included data from 3095 women with incident breast cancer who had measures of depressive symptoms and antidepressant use at baseline and at year 3. They used multivariate Cox proportional hazards regression to estimate adjusted hazard ratios between depression at diagnosis, depression at year 3, and combinations of depression at the 2 points.

The researchers found that depression at year 3 before a diagnosis of breast cancer was associated with higher all-cause mortality, after adjustments for multiple covariates (hazard ratio, 1.35). They also reported that the proportion of women with depressive symptoms alone at diagnosis was 9.4% (n=290), and the proportion of women with antidepressant use at diagnosis was 2.8% (n=87). “Compared with women without depression at the baseline, women with depression were more likely to be younger, have a higher body mass index, be physically inactive, be current smokers, have a history of postmenopausal hormone therapy, and have more comorbid conditions (all P values < .05),” they reported.

Depression prevalence at year 3 was 12.5% (n=386), and the proportion of women who had depressive symptoms alone was 8.8% (n=272), whereas the proportion of women with antidepressant use at year 3 was 4.8% (n = 149).

“Women with newly developed depression before the diagnosis of breast cancer had a modestly but significantly increased risk for death from any cause and for death from breast cancer if they were diagnosed at a late stage,” Dr Liang and the other researchers determined. “The results also highlight the importance of prevention efforts for supporting mental health and preventing the initial emergence of depression among older women.”

Reference

Liang X, Margolis KL, Hendryx M, Reeves K4, et al. Effect of depression before breast cancer diagnosis on mortality among postmenopausal women [published online April 7, 2017]. Cancer. doi: 10.1002/cncr.30688