Cancer patients treated for mental health conditions have greater risk of dying, study finds

Cancer patients who've been hospitalized for mental health problems before their cancer diagnosis face a higher risk of dying from the malignancy, say medical researchers in Canada and the United States.

The researchers are calling for more psycho-social supports, such as mental health counselling, for people with cancer. They point to emerging evidence that cancer survival rates are influenced by a patient's mental state.

The researchers, based at the University of Toronto and the Institute for Clinical Evaluative Sciences, said the findings highlight why people at risk need to be flagged and offered help, such as psycho-oncology services.

For example, social workers, music and art therapists, psychologists and psychiatrists may offer counselling and therapies to help the patient and their family cope with cancer, reduce stress and improve emotional well-being.

"As a urologist seeing cancer patients, I don't have time necessarily to sit down for 30 minutes and really figure out what they need," said Dr. Zachary Klaassen, an assistant professor and urologic oncologist at the Georgia Cancer Center. "It comes down to the oncologist's awareness and willingness to send a referral" to their psycho-oncology colleagues to get a good psychiatric history from the patient and follow up regularly.

Before, researchers weren't able to take patients' previous psychiatric history into account.

Now, Klaassen and his team have pulled together health records of more than 675,000 adult cancer patients in Ontario. By cross-referencing the records, they were able to see the bigger picture of how cancer survival related to use of psychiatric services in the five years leading up to the cancer diagnosis.

It is incumbent on specialist and primary care doctors to … perhaps be more vigilant in asking questions around psycho-social health.-  Dr. Robert Siemens

The patients in the study had been diagnosed with one of 10 common solid organ cancers (prostate, breast, colorectal, melanoma, lung, bladder, endometrial, thyroid, kidney and oral) from 1997 to 2014.

By comparing the use of mental health services of these patients to control patients who did not have a mental health issue, Klaassen found the risk of premature death from cancer worsened as the level of psychiatric help people sought increased.

About 45 per cent of the cancer patients in the study (304,559) had a psychiatric assessment as an outpatient, often by a family doctor. Another 53 per cent (359,465) hadn't used any psychiatric services.

Some possible reasons

People with bladder and colorectal cancer who received help for their mental health in the previous five years were also at greater risk of attempting suicide, Klaassen and his co-authors found.

Klaassen cautioned that the findings don't mean seeing a psychiatrist means someone will die of cancer immediately. It suggested to him that patients and their doctors may need to be more vigilant.

Why those treated for mental health conditions had a greater risk of dying of their cancer isn't known. The study's authors speculated on a few possible reasons:

• Major depression and stress may hamper the body's immune surveillance to detect and fight off cancer.
• Patients may be missing appointments, which can lead to surgery delays.
• Physicians and other health-care professionals may be consciously or unconsciously biased against these patients.

"We have to probably look at ourselves as a health-care team and say, 'Yeah, these are not the easiest patients to treat,'" Klaassen said. "They may be aggressive; they may be rude."

Bladder cancer patients twice as likely to die

The cancer patients studied had used a mental health service or had a psychiatric consult, but had not necessarily been diagnosed with a mental health condition.

In particular, bladder and bowel cancer patients who had received help for their mental health had a significantly higher chance of death compared to patients with the same cancers who hadn't had any psychiatric problems.

Bladder cancer patients with a history of hospital mental health admissions were more than twice as likely to die from their cancer, but researchers are unsure why.

In general, the risk of death from cancer was 1.73 times higher among people who were admitted to hospital for psychiatric care compared with those who didn't have psychiatric care. 

The study was published this month in the British Journal of Cancer. The study was part of a larger research project looking at the effect of mental health on cancer survival. Some of the research was presented last week at the European Association of Urology conference in Barcelona.

Dr. Robert Siemens of the urology department at Kingston General Hospital has studied the issue. He wasn't involved in Klaassen's work but recently published a review on depression and prostate cancer.

"This is important to scientists as it opens up a lot of questions to ask and answer," Siemens said in an email.

Siemens said the research highlights the potential of treatments to exacerbate or initiate psychological issues.

"It is incumbent on specialist and primary care doctors to understand this and perhaps be more vigilant in asking questions around psycho-social health," he said. "This isn't a slam dunk that its directly related, but how could it possibly hurt if we're even more focused on the whole person?"

Prostate cancer treatment tied to depression

A second study presented at the conference looked at how hormonal treatment to control cancer may increase a man's risk of depression.

The therapy suppresses testosterone, which fuels the growth of prostate tumours. But cutting off testosterone is also associated with side effects such as depression.

Siemens said urologists often see men on hormonal therapy for prostate cancer who experience low mood, depression or anxiety.

For that study, Dr. Anne Sofie Friberg from the Rigshospitalet in Copenhagen and her colleagues examined medical records of 5,570 men from the Danish Prostate Cancer Registry.

Compared with men without prostate cancer, men who had their whole prostate gland removed showed an increased risk of depression. That was based on their records of receiving antidepressant prescriptions or being referred to a psychiatric department for depression.

After surgery, erectile dysfunction and urinary incontinence are frequent symptoms.

Testosterone-blocking treatments can also change libido and lead to hot flashes that add to depression risk, the study's authors said.

The Danish research hasn't yet been peer-reviewed.