People with mental illnesses are 30 percent more likely to die from cancer, though cancer doesn’t affect them at a higher rate than those in the general population, according to a new study published in JAMA Psychology

Overall, psychiatric patients are significantly more likely to have metastasis—when cancer spreads to other organs—by the time they are diagnosed, as compared to their peers without mental disorders.

The study was conducted in Australia, and even though Australians are covered by universal health care, patients with a mental illness are less likely to receive surgery—even for colorectal, breast, and cervical cancer, for which surgery is often the first line of treatment—and they tend to receive fewer chemotherapy sessions. 

Rates of Cancer Among the Mentally Ill

Researchers at the Griffith Institute for Health and Medical Research in Australia examined the medical and death records of patients in Western Australia. They identified 135,442 new cases of cancer, of which 6,586 affected people with mental illnesses.

Researchers found that although cancer affected psychiatric patients at a slightly lower rate than the general population, these patients had a 30 percent greater chance of dying from it. This was due in part to the fact that the cancer had spread to other parts of the body by the time they were diagnosed.

Psychiatric patients are specifically more likely to die from terminal forms of colorectal, skin, prostate, and breast cancer.

What's Causing this Discrepancy?

Researchers couldn’t say with certainty why the mentally ill are dying from cancer more often than those without a history of mental disorders, but they identified these possible contributing factors:

  • Cancer goes unrecognized, especially in those with severe mental illnesses. However, scientists in Denmark (where autopsies are common) found few cases of undiagnosed cancer in schizophrenic patients.
  • People with mental illnesses receive poorer care or unequal access to appropriate care.
  • Diagnosis or screening is delayed, allowing the cancer to progress before treatment. 

The study authors also said that psychiatric patients are more likely to live in rural and/or poor areas, which may restrict their access to healthcare.

Because the survivability of cancer is dependent on early detection and proper treatment, unequal access for psychiatric patients could cost them their lives.

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