Cancer patients experience substantial psychological effects from facing death, financial issues, emotional problems with friends and family, and adverse medical outcomes from treatment. The psychological effects are so severe that some patients consider suicide.
Depression is more common in people with cancer than in the general population, said Kelly Trevino, PhD, from the Center for Research on End-of-Life Care at Weill Cornell Medicine in New York. “The prevalence of depression in this population runs between 12% and 17%, compared to approximately 7% in the general population.”
The risk of suicide also is higher among cancer patients: twice that of the general population. That higher rate is troubling for health professionals. In an effort to intervene earlier, researchers are developing a list of risk factors for depression among cancer patients. Among cancer patients, factors such as a family or personal history of depression or suicidal tendencies, drug or alcohol abuse, the recent death of someone close, and having few friends or social supports are common. Moreover, several risk factors are related to the disease itself.
People with breast, lung, head and neck, and stomach cancers have higher levels of depression than those who suffer from other cancers, probably because those cancers (or their treatments) are disfiguring and more aggressive and deadly.
“I think differences in presentation of depression are related to symptoms being the result of many different pathways,” said Kevin Patterson, MD, director of psycho-oncology at the University of Pittsburgh. “One possibility relates to the neurovegetative symptoms that constitute physical depression. These are exhibited by low energy and low motivation as well as sleep and appetite changes.”
He noted that some cancers and cancer treatments result in low energy or motivation independent of mood symptoms. Often when your body is depressed physically for a long time, that depression can become mood-based as well.
Researchers also are looking into whether chemical pathways in cancer may have a role. Certain chemicals, especially the cytokines, span the immune, endocrine, and nervous systems. The chemicals can affect all domains.
“The prevalence of depression in this population runs between 12% and 17%, compared to approximately 7% in the general population.”
“The likelihood that there exists a chemical pathway able to depress the nervous system is very high,” Patterson said. Although several studies support that supposition, “nothing has been shown to be the singular explanation—probably because you are seeing various combinations of these and other pathways.”
Over the last five years or so, the already extensive research into that area has intensified. One of the drivers is the distress-related screening and treatment protocols required for Cancer Center certification from the American College of Surgeons’ Commission on Cancer.
To address some of those issues, the American Society of Clinical Oncology (ASCO) published an adapted guideline for screening, assessing, and caring for anxiety and depression in adults with cancer. In the Journal of Clinical Oncology, ASCO suggested evaluating symptom presence throughout the time of care by using validated scales and procedures.
ASCO recommends that doctors use the Personal Health Questionnaire (PHQ-9) for screening purposes. That nine-question instrument is used to screen, diagnose, monitor, and measure the severity of depression. The first two questions are used for screening and ask about a patient’s level of interest or pleasure in doing things and whether the patient is feeling down, depressed, or hopeless. If the answer to either question is yes, ASCO recommends that patients fill out the rest of the questionnaire. The final questions of the PHQ-9 concern the length and severity of symptoms and are used in diagnosis and monitoring. Those questions ask about symptoms of depression such as sleep disturbances, eating habits, and concentration problems. One question assesses the possibility of suicidal thoughts or actions.
The guidelines suggest periodic screening throughout cancer treatment. Researchers agree that increased vigilance is important at specific times, such as within the first two or three visits and at transition points such as those outlined earlier.
“I don’t know that we have any good data on how often to screen,” said Dale Theobald, MD, PhD, who has been senior medical director for palliative, hospice, and home health care at Community Health Network in Indianapolis. “Certainly you don’t want to pester a patient with big checklists at every appointment. [But] I think an important part of any office visit is asking about how they are feeling, their energy level, and their current mood.”
The results of those questions could then be used to guide the provider’s decision on whether to follow up with a more structured and formal evaluation. And although completing screening tools is important, other considerations depend on the instincts of the provider.
“Most practitioners get to know their patients, and if they think there is an additional risk of depression or suicide they should pay special attention,” Massie said. “Clinicians contact me all the time asking me if I can see their patient sooner rather than later. Something just doesn’t feel right and they are worried.”
Although large facilities may have adequate staff to help, those concerns are worse at the community level where most patients are treated. Addressing that gap would require the large centers and their smaller counterparts to work together.
“When we studied oncologists’ ability to recognize depression in their patients, we realized it is hard to distinguish depressive symptoms from other cancer treatment and cancer disease–related symptoms—such as fatigue,” Theobald said. “We realized the importance of using valid screening processes to make treatment of depression in cancer patients more effective. In later trials we documented that careful use of standard antidepressants is an effective way to treat this common illness.”
“Overall there is great hope,” Theobald said. “Depression associated with cancer can be treated effectively.”
Featured image credit: CAT scan May 2015 by liz west. CC BY 2.0 via Flickr.