Suicide risk quadruples for people with cancer, study finds

New research from the Penn State College of Medicine shows people with cancer are more than four times more likely to die of suicide than those without cancer, highlighting a need for a more comprehensive approach to treatment.

“Even though cancer is one of the leading causes of death in the United States, most cancer patients do not die from cancer. The patients usually die of another cause,” Penn State radiation oncologist Nicholas Zaorsky said in a university article. “There are multiple competing risks for death, and one of them is suicide.”

For the study, published Monday in the journal Nature Communications, researchers examined data on more than 8.6 million cancer patients in the United States (28 percent of the country’s population) from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program. They looked at patients’ age, cancer incidence, survival, treatment, year of diagnosis and more.

All of the patients had been diagnosed with invasive cancer between 1973 and 2014.

Researchers found that .15 percent of the dataset — 13,311 cancer patients — died by suicide, a rate of 28.58 per 100,000 people. That’s more than four times the general population’s risk, according to Penn State. Elderly, unmarried white males with localized disease were at the highest risk.

The latest data reveals a two-fold increase from a similar 2002 study, which reported people with cancer had an increased risk of 1.9 times the general population.

Risk of suicide generally decreased five years after a cancer diagnosis, but remained high for those with Hodgkin lymphoma and testicular cancer. Previous research has also pointed to the prevalence of psychiatric illnesses like anxiety and depression among HL patients and increased suicide risk in patients with testis cancer.

Those with cancer of the prostate, lung, colorectum or bladder; as well as people with lymphomas, leukemias or germ cell tumors were considered most at risk.

The 2002 study, in contrast, found head and neck cancer patients were at greatest risk of suicide compared to the general population, “which may be secondary to the shifting distribution of human papilloma virus-associated cancers, and a decrease in those associated with tobacco and alcohol,” researchers wrote.

Age of diagnosis was also a significant factor in assessing suicide risk.

“Treatments for some cancers — like leukemia and testicular cancer among adolescents and young adults, for example — can decrease a patient’s fertility, and that seems to be one of the risks for suicide in the long term,” Zaorsky said. “In contrast, elderly patients who are diagnosed with lung, prostate, and head and neck cancers are at an increased risk of suicide for the remainder of their life.”

Researchers acknowledged potential limitations of the study, including possible overestimates of standardized mortality rates due to treatment and follow-up changes over the decades, plus potential risk of misclassification of suicide in the SEER database. Still, researchers note any errors are likely less frequent than hospital-based databases and databases like SEER's are an "integral part" of such medical research.

What clinicians can do, according to researchers

According to the study, “there is currently no contemporary resource to assist clinicians, including oncologists and psychiatrists, in identifying cancer patients at highest risk of suicide.”

Zaorsky noted that the new findings, particularly regarding the risk differences by age of diagnosis and cancer type, may help clinicians and other experts develop suicide-prevention strategies aimed at the elderly population or at individuals with certain cancers, such as cancer of the prostate, lung, colorectum, and bladder; as well as patients with leukemias, lymphomas, and germ cell tumors.

Additionally, researchers call for a more comprehensive treatment approach from psychiatrists and oncologists through survivorship programs, “which aim to care for and improve the quality of life for cancer patients that have gone through treatment and are on their way to recovery.”

"We're in a very different place than we were even in the 1990s," University of Pennsylvania nurse practitioner Linda Jacobs told U.S. News in a 2017 special on survivorship programs. "People are now living with cancer as a chronic illness."

In fact, “there are 15.5 million Americans now who are living as cancer survivors, and that number is expected to rise past 20 million by 2026 because of improvements in detection and treatment,” U.S. News reported.

Through survivorship programs, which originates from pediatric oncology, clinicians can address long-term effects of cancer, such as feelings of hopelessness; stress of financial burdens; fertility and dating concerns; body image issues and other types of emotional distress.

Zaorsky and his team recommend that providers also continue to follow the evolving guidelines for monitoring distress and suicide prevention from the American College of Surgeons Committee on Cancer, the American Society of Clinical Oncology, the National Comprehensive Cancer Network, and Action Alliance for Suicide Prevention.

There has been a nearly 30 percent increase in suicide rates between 1999-2016 in the U.S., according to the Atlanta-based Centers for Disease Control and Prevention. Between 1996 and 2016, Georgia experienced a 16.2 percent increase in suicide rates, comparatively low among the 25 states where suicide rates rose by nearly 30 percent. But that's still considered a significant increase, according to the CDC.

The number of cancer deaths has nearly tripled from 210,733 in 1950 to 576,691 in 2011, largely due to the aging population. And according to the National Cancer Institute, approximately 38.4 percent of men and women will be diagnosed with cancer at some point during their lifetimes.

You can find the full study at nature.com.