Risk for Suicide Spikes After Cancer Diagnosis

Roxanne Nelson, RN, BSN

January 17, 2019

Receiving a cancer diagnosis can be overwhelming and cause undue distress to patients and their families, but two new studies show that it also increases the risk for suicide.

One of the studies, published in Cancer, found that the risk for suicide was significantly increased for a year after the cancer diagnosis, and the overall risk for suicide was about 2.5 times higher than among the public at large.

The other study, published in Nature Communications, found that cancer patients are about four times more likely die by suicide as compared to the general population.

Both studies found that the risk for suicide varied for different types of cancer and that it was particularly high after a diagnosis of lung cancer. In one study, it was also particulalry high after a diagnosis of pancreatic cancer.

"We believe that the initial shock and anxiety resulting from unclear or misinterpreted healthcare messages on the Internet or elsewhere can be responsible for this," commented co–senior author Ahmad Alfaar, MBBCh, of Charité–Universitätsmedizin Berlin, Germany.

This is the time when emotional support by the clinical team and physician is extremely important, he emphasized. "Mental healthcare plans must be integrated in day-to-day life of the patient during their journey with cancer," Alfaar told Medscape Medical News.

Suicide Risk in the First Year

"Our study was the first to dissect the first year, interpret the suicide risk over time, and compare it to follow-up period," Alfaar commented about the study published in Cancer.

These researchers used data from the Surveillance, Epidemiology, and End Results Program (2000-2014) to identify 4,671,989 cancer patients. Within that cohort, the team found that 1585 patients had died by suicide within 1 year of their diagnosis. The risk for suicide increased significantly, with an observed/expected (O/E) ratio of 2.52 and with an excess risk of 2.51 per 10,000 person-years.

Within the first 6 months following diagnosis, 1062 patients died by suicide. The O/E ratio in this period was higher than for the second 6 months (3.13 and 1.8, respectively). The greatest increase in risk occurred during the second month after receiving a cancer diagnosis, with an O/E ratio of 4.81. It was even higher for patients with distant metastases (O/E ratio, 5.63).

The findings were not entirely surprising, Alfaar commented to Medscape Medical News.

"However, finding results that complement the medical knowledge about cancer and the feeling of the patients about their diseases was really an interesting journey," he said in an interview. "These findings give us an idea about the progression of the patients' feelings when they first receive their diagnosis from their doctors or they read on the Internet about prognosis of their diseases and misinterpret these messages."

Closer monitoring and more attention needs to be paid to the emotional/mental health of cancer patients as part of treatment and follow-up. "The mental health plan has to be interactive so as to measure the levels of stress/anxiety of the patient and adapting itself to support him/her over the diagnosis and treatment period and extending to the patients' life thereafter," Alfaar told Medscape Medical News.

"Psychological complications of cancer management can extend lifelong. This has also to involve not only the psychiatrist but all members of healthcare team, family, and friends," he added.

Greatest Risk for Pancreatic and Lung Cancer

This study also evaluated suicide risk with regard to specific cancer sites. The team found that the highest increases in suicide rates followed diagnoses of pancreatic cancer (O/E ratio, 8.01) and lung cancer (O/E ratio, 6.05). The risk for suicide also increased significantly after a diagnosis of colorectal cancer (O/E ratio, 2.08), but no significant increase in suicide risk was noted after a diagnosis of breast cancer and prostate cancer.

"The findings reflected the advances that happened in the last few decades in the management of certain cancers," Alfaar said. "Research on certain cancers showed more targeted funding than others."

As an example, research funding for breast cancer by the National Cancer Institute was three times that for pancreatic cancers in 2017. "This is something that has to be considered by policy makers," he said.

The increase in suicide was greater in men than women (O/E ratios, 2.66 vs 1.86), but the ratios changed in accordance with age. There was an overall higher risk for suicide for patients older than 40 years, and this risk remained higher in men until after the age of 84 years, at which point it became higher in women (O/E, 3.4 vs 2.68).

Alfaar noted that there are many contributing factors to suicide risk. "For example, women or married people are less liable to die by suicide after a diagnosis of cancer, while Asian/Pacific Islanders and American Indians and Alaska Natives and those with advanced disease stages showed more risk for suicide," he said. He added, however, that "subgroup analysis is not possible if the number of patients is small."

These are also direct correlations. "Patients with cancers that have had less research funding, and hence less advancement in therapeutics, showed more risk for suicide," Alfaar explained. "Disparities in healthcare, including access to care, can be another factor."

Quadruple the Risk

The other study, published in Nature Communications, also used data from the SEER program (1973-2007).

Lead author Nicholas Zaorsky, MD, an assistant professor in the Department of Radiation Oncology at the Penn State Cancer Institute, Hershey, explained: "Our goal was to quantify the risk of suicide among cancer patients."

The team identified 8,651,569 cancer patients in the SEER database and found that 13,311 had died by suicide. This extrapolated to a rate of suicide of 28.58/100,000-person years. The standardized mortality ratio (SMR) of suicide was 4.44 (95% confidence interval, 4.33 - 4.55).

As in the first study, the authors also found that certain subgroups were more at risk than others. Those patients who were most likely to die by suicide were male (11,042, 83%), white (12,258, 92.1%), and those who were diagnosed at a younger age.

For example, for patients who were diagnosed when younger than 39 years, the SMR was 37.24 (P < .0001). By comparison, for patients who were diagnosed when they were older than 80 years, the SMR was 2.40 (P < .0001). The highest SMR of death from suicide occurred for patients with metastatic/distant disease at diagnosis (n = 1753; 13.2%; SMR, 13.19; P < .0001).

Suicide risk also varied by cancer type, age, and time from diagnosis. For lung cancer patients, for example, the SMR was 25 (P < .0001) in the first year following diagnosis, but that declined as time passed. In contrast, for patients with Hodgkin lymphoma, the SMR was 26 (P < .0001) in the first year following diagnosis, but that remained high over time.

Overall, although the SMR of suicide generally declined over time for most cancers, it remained high for several types, including Hodgkin lymphoma and prostate cancer. In some cases, such as testicular cancer, it increased over time.

Because the data were drawn from a database, the reasons for suicide could not be addressed, especially with respect to specific patient groups. The reasons why certain subsets of patients with certain cancer types are more likely to be distressed and/or depressed and suicidal "would be a great topic of another study," Zaorsky told Medscape Medical News.

"But one of the hypotheses that we had was that younger patients with cancer can become infertile from their therapy," he said. The researchers speculate that this could be a factor in the risk for suicide in the long term.

On the basis of their findings, the researchers suggest that suicide prevention strategies may be aimed at older patients with cancer of the prostate, lung, colorectum, and bladder, as well as those with leukemias, lymphomas, and germ cell tumors.

Dr Alfaar is supported by the German Academic Exchange Service. The other authors of both studies have disclosed no relevant financial relationships.

Cancer. Published online January 7, 2019. Abstract

Nat Commun. Published online January 14, 2019. Full text


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