New Study Finds a Link Between Depression and Breast Cancer Survival

Depression and anxiety are (understandably) more common in people with a cancer diagnosis. It’s estimated that as many as one in four people with cancer also have depression, according to the National Cancer Institute.

A new study, published April 17 in the American Cancer Society’s journal Cancer, suggests that for women with breast cancer, depression may negatively impact the care they receive and their chances of survival.

The key takeaway from the study is that untreated depression is associated with decreased survival among female breast cancer patients, says the lead author, Bin Huang, PhD, an associate professor at the Markey Cancer Center in Lexington, Kentucky. “Depression management is important for breast cancer patients after diagnosis, as is maintaining continuity of care for patients with a depression pre-diagnosis. It can ultimately affect the patient’s long-term survival,” he says.

This study supports previous research that depression can impact the likelihood of cancer survival. A meta-analysis of studies involving more than 20,000 patients with several different types of cancer, including breast cancer, found that across all cancer diagnoses, major depression was associated with worse survival. The meta-analysis appeared in 2021 in the journal Psychosomatic Medicine.

Breast cancer accounts for an estimated 30 percent of all new female cancers each year, second only to skin cancer, according to the American Cancer Society. There is a one in eight chance that a woman will develop breast cancer in her lifetime.

Women Who Were Depressed After Cancer Diagnosis Had a 50 Percent Higher Risk of Death

Researchers used data from the Kentucky Cancer Registry to identify more than 6,000 adult women diagnosed with primary invasive breast cancer from 2007 to 2011.

Health claims information was used to put those women into one of four categories:

• No depression: 86 percent
• Depression diagnosis only before cancer diagnosis: 3.7 percent
• Depression diagnosis only after cancer diagnosis: 6.2 percent
• Persistent depression (depression before and after cancer diagnosis): 4.1 percent

During a median follow-up of four years, 26.2 percent of the women died.

Depression before diagnosis was associated with a 26 percent higher risk of death, and depression post-diagnosis was associated with a 50 percent higher risk of death compared with women who did not have depression.

The findings suggest that diagnosis and treatment of depression at the time of breast cancer diagnosis and beyond can be critical to patient care and survival, says Dr. Huang.

“We initially were surprised that the breast cancer patients with a depression diagnosis before and after a cancer diagnosis did not have a higher risk of mortality than the breast cancer patients without a depression diagnosis,” Huang says. “After further consideration, we realized that having a depression diagnosis before and after a cancer diagnosis indicates that patients’ depression may have been well managed, given that underdiagnosis and undertreatment of depression are common among cancer patients.”

He concludes, “This suggests the importance of depression management in patients’ cancer care.”

Nearly 3 in 10 Women Didn’t Receive Guideline-Recommended Breast Cancer Treatment

In addition, the Kentucky investigators assessed the care that participants received to see if it was appropriate according to the National Comprehensive Cancer Network breast cancer treatment guidelines.

Researchers found that nearly 30 percent of patients did not receive guideline-recommended breast cancer treatment.

“That’s a huge number of patients,” says Preeti K Sudheendra, MD, a medical oncologist who specializes in breast cancer at the Ohio State University comprehensive cancer center in Columbus, who was not involved in this research.

Women with post-diagnosis depression or persistent depression were just as likely to get guideline-recommended treatment as women with no depression, but women with depression before their diagnosis were 25 percent less likely to get the appropriate care.

The risk of death for women who did not receive guideline-recommended treatment was more than double that of those who received recommended care, according to the study authors.

This research was not designed to investigate the reasons why those women didn’t receive the appropriate care, and it would be useful if future investigations could further explore that, says Dr. Sudheendra.

It does make sense that depression could impact care, she says. “For example, having preexisting depression before a diagnosis may cause someone to be less engaged in their health or maybe delay a diagnosis or a workup.”

More Research on Depression Treatment in People With Cancer Is Needed

Future studies could investigate how depression may impact care along the treatment continuum so that actionable steps could be taken to improve outcomes, says Sudheendra.

“Hopefully, if a patient’s depression is adequately treated, their outcomes would be more in line with someone without depression,” she says.

Even though depression is very common in people with cancer, there are very few high-quality studies that look at the potential benefits of antidepressants in treating depressive symptoms in people with cancer, according to a Cochrane review published on March 31, 2023.

The authors concluded that there was a “small potential benefit” and that the evidence suggests that people with cancer who are depressed should get the same treatments for depression as the general population.

People in Rural Areas May Lack Mental Health Resources

Because of a lower presence of community mental health clinics and shortages of mental healthcare providers in Appalachia, depression may be underdiagnosed among patients there, says Huang.

“Access to mental health resources is really important; one of the questions raised by this study is whether depression is being adequately treated. My hypothesis is that given the rural setting that many of these women live in, a lot of medical conditions, including depression, may have to be managed by their family doctors. Did patients feel that that was enough?” says Sudheendra.

Changes in Mood or Behavior Should Be Discussed With a Healthcare Professional

“At our cancer center, we do a distress screening that assesses different concerns, including emotional concerns such as worry, feelings of worthlessness, and depression,” says Sudheendra.

“If the assessment meets a certain threshold, then those patients get referred to social work or our counselors, which in our group is called psychosocial oncology,” she says.

Unfortunately, a stigma remains around mental health issues, says Sudheendra. “If the patient or their family member notices any changes in their mood or behavior, they should bring it to a physician’s attention,” she says.

What signs of depression should you look for? According to the Susan G. Komen breast cancer organization, if any of the symptoms listed below last longer than two weeks, you may have clinical depression and should talk to a healthcare professional right away.

• Feel sad most of the time
• Have lost pleasure in activities you used to enjoy
• Have poor concentration
• Feel nervous
• Feel tired for no reason
• Have a change in eating or sleeping habits
• Withdraw from friends and family
• Feel hopeless, worthless, or guilty
• Have frequent thoughts of death or a desire to die

If your healthcare provider isn’t able to adequately treat your depression and there are no mental health professionals in your area, look online for virtual services that could help, says Sudheendra.