Men who have prostate cancer (PCa) are at increased risk of suicide and accidental death within the first year of diagnosis compared with their counterparts diagnosed with other solid malignancies, according to a new study. The risk also is increased when definitive treatment was recommended but not received.
The findings suggest “the need for close monitoring and coordination with mental health professionals in at-risk men with potential curable disease,” the authors concluded in a paper published online ahead of print in BJU International.
A team led by Quoc-Dien Trinh, MD, assistant professor of surgery at Harvard Medical School in Boston, noted that while substantial research has demonstrated a relatively higher risk of suicidal death among PCa patients compared with the ‘cancer-free’ population, “to our knowledge we present the first report directly comparing the risk of suicidal death in men with PCa to those with other solid cancers.”
Previous research has documented that patients diagnosed with cancer, regardless of the anatomic site involve, have a greater burden of psychiatric illnesses, Dr. Trinh’s group noted. “By using patients with other cancers as a comparison group,” the authors wrote, “we attempted to mitigate the confounding impact of psychiatric disorders (and other pre-existing comorbidities) amongst patients with cancer in determining suicide risk, potentially allowing more direct association of PCa with suicidal mortality.”
The study included 524,965 men diagnosed with PCa and 956,576 men diagnosed with other solid cancers.
Using 1988–2010 data from the Surveillance, Epidemiology and End Results (SEER) database, the researchers studied 524,965 men diagnosed with PCa and 956,576 men diagnosed with other solid cancers. The investigators found that the risk of suicidal or accidental death was lower among men with PCa than those with other cancers (0.2% and 0.6%, respectively, vs. 0.2% and 0.5%, respectively), except within the first year of diagnosis. For example, from 0–3 months after diagnosis, PCa patients had a 4-fold increased adjusted relative risk of either suicidal or accidental death compared with their counterparts with other solid cancers. Among men who were recommended treatment but did not receive it or refused it, those with PCa had a significant 32% increased risk of a suicidal death and 44% increased risk of accidental death.
The authors discussed possible reasons for the higher suicidal and accidental risks observed in their study. Although the higher risk may be partly attributable to unmeasured baseline differences between patients with PCa and those with other solid cancers, Dr. Trinh and colleagues cited studies suggesting it may also reflect a disproportionately high immediate psychosocial impact of the PCa diagnosis, fueled by perceived anxiety of treatment-related adverse effects in younger men and uncertainty regarding watchful waiting in older patients. Clinical depression associated with a PCa diagnosis, distress secondary to treatment indecision, or treatment-related adverse effects such as urinary incontinence and erectile dysfunction that impair quality of life may contribute to a heightened suicidal risk, the authors stated. Patients diagnosed with PCa experience negative intrusive thoughts and significant decrements in physical, mental, and social aspects of their lives, particularly within the first 6 months of diagnosis, according to the investigators.
The new findings corroborates those of previous studies. For example, Swedish investigators who compared 105,736 men with PCa and 528,658 matched PCa-free men found that the PCa group had a 6.5-fold increased relative risk of suicide, Sigrid Carlsson, MD, and colleagues reported in the European Journal of Cancer (2013;49:1588-1599). Men with low-risk PCa had a 5.2-fold increased relative risk and those with distant metastases had a 10-fold increased relative risk.
“Although the increase in absolute risk of suicide was modest,” the researchers concluded, “our findings reflect the severe psychological stress that prostate cancer patients may experience after diagnosis.”