Patients with cancer have a higher suicide risk

Two recent studies published in Nature Medicine show that people with cancer are at an increased risk for suicide and self-harm. In one report, a meta-analysis of 28 studies found that, among patients with cancer, the suicide rate was nearly twice that of the general population (standardized mortality ratio [SMR], 1.85).1 The study, which included more than 22 million patients, found that having a poor prognosis put patients at the highest suicide risk. Those at highest risk included those with esophageal cancer (SMR, 6.01), liver and biliary system cancer (SMR, 3.13), mesothelioma (SMR, 13.07), and pancreatic cancer (SMR, 6.42). Suicide mortality among patients with cancer was significantly higher in the United States as compared with Europe, Australia, and Asia. These differences were not found in an analysis of the general population. “Our findings imply that clinicians should be aware of the increased risk of suicide among patients with cancer,” says Corinna Seliger-Behme, MD, PhD, senior author of the study and a senior physician in the Department of Neurology at University Hospital Heidelberg in Germany. “Clinicians should carefully monitor their patients for signs of depression and suicidality to involve specialized psycho-oncological care as early as possible. Special attention should be given to patients with a poor prognosis, late-stage disease, and [those] within the first year after diagnosis, especially in the US.” Researchers of the second article analyzed the health records of 459,542 individuals in the United Kingdom aged 18 years or older who had been diagnosed with 26 cancer types.2 Senior author Alvina Lai, PhD, an associate professor at the Institute of Health Informatics at University College London, and her colleagues found that, overall, depression was the most common psychiatric disorder among people with cancer, followed by anxiety disorders, schizophrenia, bipolar disorders, and personality disorders. More than 25% of the study participants had a substance abuse disorder. This United Kingdom study found that more than 1% of patients reported engaging in self-harm after their cancer diagnosis. Rates of self-harm were higher among those who had an existing psychiatric diagnosis prior to their cancer diagnosis. Among the five psychiatric disorders analyzed—depression, anxiety disorders, schizophrenia, bipolar disorders, and personality disorders—the highest rate of self-harm occurred in individuals with depression, especially within a year of their cancer diagnosis (adjusted hazard ratio, 44.1). Patients who harmed themselves were 6.8 times more likely to die of unnatural causes (suicide and accidents), as compared with those in the control group, within 12 months of self-harm (hazard ratio, 6.8; 95% confidence interval, 4.3–10.7). “Special attention should be given to patients with a poor prognosis, latestage disease, and [those] within the first year after diagnosis, especially in the US.” —Corinna Seliger-Behme, MD, PhD “These are very interesting and important studies,” said Timothy J. Moynihan, MD, an expert with the American Society of Clinical Oncology and an emeritus medical oncologist at Mayo Clinic, who was not involved with the research. “I am not aware of any other studies that are as large as these two that examine the link between suicide risk and cancer. We have known for some time that suicide risk is increased in patients with cancer, but these two studies help to put that risk into perspective and stress the need for all caregivers to be aware of the risk of suicide, to screen for it prospectively, and to have a team identified that can facilitate early treatment to help prevent this complication of cancer.”