Study: PTSD raises suicide risk for those with prostate cancer
January 26, 2021
By Mike Richman
VA Research Communications
"We think it's possible that prostate cancer treatment may help to reduce suicide risk by alleviating some of the stress and anxiety inherent to a cancer diagnosis."
Studies have shown that PTSD is one of the most common mental health diagnoses among men with prostate cancer. Yet, research on the link between PTSD and prostate cancer, particularly on how PTSD may influence suicide risk in this population, has been limited.
Now, a VA-funded study led by Dr. Maya Aboumrad of the White River Junction VA Medical Center in Vermont sheds light on these questions. The study found that patients with prostate cancer and PTSD experienced greater suicide risk than men with prostate cancer and no PTSD, even after adjusting for factors such as depression, substance use disorder, and prostate cancer treatment.
Conversely, the researchers concluded that men with prostate cancer and PTSD may have been at lower risk of death from non-suicidal causes due to favorable physical health resulting from greater health care use and early diagnosis of localized—or low-risk—cancer.
The results appeared online in the journal Psychooncology in November 2020.
“We showed that men with preexisting PTSD and a new prostate cancer diagnosis experienced improved non-suicide survival despite being at greater suicide risk,” the researchers write. “We encourage collaboration between oncology and psychiatry providers when treating patients with PTSD and newly diagnosed prostate cancer. We hope this may mitigate some of the increased suicide risk shown in the current study. Given the high prevalence of PTSD and prostate cancer among Veterans, understanding the interplay between the two diseases warrants further study.”
The primary goal of the study was to assess the impact of a PTSD diagnosis on suicide and non-suicide death rates among Veterans with prostate cancer. “This population is of
particular interest given its higher rates of prostate cancer, suicide, and PTSD, as well as poorer engagement in preventative care, such as screening for prostate cancer,” the research team writes. “Our secondary [goal] was to examine potential mediating factors for the [link] between PTSD and suicide, including depression, substance use disorder, and receipt of any definitive prostate cancer treatment.”
‘Dive deeper into these findings’
Aboumrad and her colleagues decided to pursue the research after one of their prior studies showed that patients with prostate cancer and mental health conditions, including PTSD, had a higher suicide risk. “We wanted to dive deeper into these findings by learning more about the specific factors that contribute to or alleviate this risk for a vulnerable population, in this case those with mental health conditions,” she says. “In order to adequately examine suicide risk for patients with prostate cancer, we had to consider competing risk of death from other non-suicidal causes.”
“Patients with PTSD, with or without prostate cancer, may have an elevated risk of suicide compared to those without PTSD,” she adds. “It’s also true that patients with prostate cancer, with or without co-existing mental health conditions, may have an elevated risk of suicide compared to those without prostate cancer. Our study highlighted the apparent exacerbation of suicide risk for patients with prostate cancer and PTSD. In other words, the risk is compounded for patients that have both suicide risk factors.”
In VA, prostate cancer is one of the most commonly diagnosed forms of cancer among Veterans, many of whom also have PTSD. The disease is most common in men ages 65 and older. Prostate cancer is usually found in its early stages and often grows slowly. Most men live with the cancer for decades without symptoms and die of other causes even without early surgery.
Research has shown that PTSD greatly increases someone’s risk for suicidal ideation, which is the thought of taking one’s own life. But findings are mixed as to whether PTSD elevates risk for death from suicide. PTSD symptoms include flashbacks, nightmares, hypervigilance, aggressive behavior, and severe anxiety. Patients with other types of cancer are also at increased risk of suicide.
In addition to potentially conferring greater suicide risk, Aboumrad’s study notes, the presence of mental illness, such as PTSD or depression, can negatively impact diagnosis, treatment, and survival of patients with prostate cancer. Research, she says, has shown that patients with mental illnesses may be less likely to take part in preventative care, including prostate cancer screening, which could lead to the development of diseases at later stages, such as metastatic cancer. “They have also been found to be less likely to engage in prostate cancer treatment,” Aboumrad says. “Collectively, these factors could contribute to poorer overall health and survival.”
PTSD a major suicide risk factor on its own
Aboumrad’s retrospective study included more than 200,000 Veterans with prostate cancer—about 6% of whom also had a PTSD diagnosis in the year before prostate cancer diagnosis. Compared to the Veterans without PTSD, those with the mental health condition were younger (under age 65); they experienced more baseline co-existing health conditions, including chronic pain, sexual dysfunction, and sleep disorder; and they had lower-risk prostate cancer at diagnosis.
Plus, many more patients with PTSD used more health care services, compared to those without PTSD. Patients with PTSD also experienced more baseline suicide risk factors, including more than six times as many with depression and five times as many with substance use disorder.
The researchers used data in VA’s electronic health record. Their findings showed that almost two times as many patients with PTSD died by suicide (0.21% versus 0.13%), while half as many died from circumstances not related to suicide (12% versus 23%). PTSD was a major suicide risk factor on its own, even after considering the influence of depression, substance use disorder, and prostate cancer treatment.
“It is possible that patients with prostate cancer and PTSD experienced better non-suicide survival due to less severe cancer as a result of greater use of healthcare services, more PSA screening, and earlier diagnosis,” the researchers write. “We found that more of these patients experienced pain, sexual dysfunction, and/or sleep disturbances. This exacerbation of conditions among patients with PTSD could have resulted in more frequent health care visits. Additionally, they may have had more opportunities to discuss these symptoms during their mental health visits for PTSD. Since prostate cancer screening is often routine during health care visits, patients may have experienced better physical health due to earlier detection of less severe cancer.”
The PSA (prostate specific antigen) blood test is one of the most common screening tools for prostate cancer.
Patients with PTSD less likely to get prostate cancer treatment
Aboumrad and her team also determined that patients with PTSD and prostate cancer were more likely to use health care services, compared to patients with prostate cancer who do not have PTSD.
“We found that patients who received any prostate cancer treatment had a lower suicide risk compared to untreated patients, and we also found that patients with PTSD were less likely to undergo prostate cancer treatment,” Aboumrad says. “We think it’s possible that prostate cancer treatment may help to reduce suicide risk by alleviating some of the stress and anxiety inherent to a cancer diagnosis. We believe that determining a treatment plan with optimal physiological and psychological impact for patients with prostate cancer and mental health conditions will require collaboration between oncology and psychiatry providers.”
The study findings, according to the researchers, highlight the importance of considering psychiatric illnesses when treating patients with prostate cancer, as well as the need for strategies to reduce suicide risk.
“In the clinical setting, recommendations to pursue prostate cancer treatment are often determined by tumor characteristics,” Aboumrad says. “Mental health conditions are not routinely considered in this treatment decision-making process. We hope to further explore the potential role of prostate cancer treatment for reducing suicide risk among patients with PTSD and other mental health diagnoses.”