Elderly with Cancer Have Increased Suicide Risk

November 14, 2008

A new study shows that elderly patients with cancer are at greater risk for suicide than those with other illnesses. This increased risk persisted after accounting for comorbid psychiatric illness and risk of dying within a year.

A new study shows that elderly patients with cancer are at greater risk for suicide than those with other illnesses. This increased risk persisted after accounting for comorbid psychiatric illness and risk of dying within a year. “Previous studies have suggested that some types of physical illness were associated with elevated rates of suicide but few US studies controlled for several medical and psychiatric comorbidities at the same time,” said lead author Mathew Miller, MD, ScD, associate director of the Harvard Injury Control Research Center in Boston, Massachusetts. “We were able to compare an older group of Americans to see if there were some diseases that really stuck out as putting patients at high risk compared to other physical ailments, above and beyond any associated psychiatric condition.”

Researchers reviewed data for 128 residents of New Jersey aged ≥65 years who committed suicide according to information from the Department of Vital Statistics and had been enrolled in New Jersey’s Medicare Pharmaceutical Assistance Program for the Aged and Disabled (PAAD) when they died. The control group included 1280 individuals frequency-matched by age and sex to the decedents.

Investigators analyzed data using the odds ratio (OR) of suicide adjusted for age, sex, ethnicity, medical and psychiatric comorbidity, and use of prescription medicines. The adjusted analysis showed that cancer was the medical condition most strongly associated with suicide. The use of opioid analgesics was also associated with suicide, as were various psychiatric diagnoses. “We found that the risk of suicide is higher in older Americans with cancer than among those with other medical conditions even after controlling for psychiatric illness, use of pain medication, and probability of dying from their physical illness within a year,” said Dr. Miller. “We don’t have an empirical grasp of why this occurs.”

The most salient feature to emerge, according to the researchers, was the disproportionate numbers of those with metastatic disease who committed suicide. “Although our study was too small to assess risk differences between the various types of cancers, patients with metastatic disease had a higher risk of dying by suicide than those whose cancer was localized,” Dr. Miller explained. “We did not have large enough numbers to see if some cancers were more likely than other cancers to predispose more patients to take their lives.”

Many patients included in the study saw a clinician within a week of their suicide. Dr. Miller said that this underlines that there are opportunities to intervene. Oncologists should be aware that even routine visits might provide an opportunity to prevent patient suicides. “It is easier said than done,” Dr. Miller acknowledged. He added that when physicians suspect patients may be at risk of suicide, they talk to them about alternatives and suggested “one of the topics should be removing guns from their homes since nearly 63% of cancer patients killed themselves using firearms.”

Some clinicians are concerned that discussing suicide with their patients may plant the idea and lead to a suicide attempt. There is no evidence from any source that supports the idea that discussing suicide increases the incidence. “The greater concern should be in not talking to someone about their emotional wellbeing,” Dr. Miller said. “We should not hide behind this unsubstantiated clinical myth that talking about suicide will lead to suicide. On the contrary, there is good evidence that if you can get people to get rid of guns or think about alternatives to suicide, you can help them in a very meaningful way.”

Timothy Quill, MD, director of the Center for Ethics, Humanities, and Palliative Care at the University of Rochester Medical Center in New York, was not involved in the study but he said it provides a glimpse of what is going on with some patients who have cancer. However, he perceives it as looking at the issue from a distant perspective, with little detail visible. “The take away is that patients are thinking about suicide much more commonly than they let us know,” he said. Dr. Quill emphasized the need for physicians to keep their eyes open and remain vigilant for patients experience a major change in their status and said they should “ask about these issues.”

Many oncologists develop close relationships with their patients as they go through intensive treatment regimens. The physicians and their teams are uniquely positioned to identify patients at increased risk for suicide and attempt to get them the support they need. “The scary part is that many people can be under the radar screen and have worries, concerns, or even plans, and we may not see the suffering if we don’t have our eyes open,” said Dr. Quill. “These results are clearly a red flag to intensify both exploration of their experiences and screening for depression, hopelessness, or suicidal thoughts.”

Mary Whooley, MD, staff physician, Medical Service, San Francisco Veteran’s Affairs Medical Center, California; and Gregory Simon, MD, MPH, a psychiatrist with GroupHealth Center for Health Studies, Seattle, Washington, have studied depression in various patient groups and advocate the following 2-question test, which they claim is 96% sensitive in detecting depression:

• In the past month, have you felt “down,” depressed, or hopeless?

• In the past month, have you had little pleasure or interest in doing things?

Patients who answer “yes” to both questions require further evaluation to determine a specific diagnosis. Physicians can also consider giving patients the Zung Depression Scale (www.healthnet.umassmed.edu/mhealth/ZungSelfRatedDepressionScale.pdf), a brief depression screening handout patients can self-administer. The Beck Depression Inventory is another self-administered screening test widely used in the clinical setting. Dr. Whooley suggested that patients who admit to having destructive thoughts should be referred to a mental health provider immediately, whereas patients with less severe depression symptoms may be able to wait a few weeks to see whether symptoms persist before seeking treatment.

Miller M

J Clin Oncol

, et al. Cancer and the risk of suicide in older Americans. . 2008:26:4720-4724.

Author Kurt Ullman is a freelance health and medical writer based out of Indianapolis, Indiana.

Additional reading for healthcare professionals:

National Cancer Institute: Assessment, Evaluation, and Management of Suicidal Patients