The widespread use of the prostate-specific antigen, or PSA, test for detecting and monitoring prostate cancers since 1993 may have lowered the risk of suicide after a diagnosis of prostate cancer, possibly by showing many men that their tumors are not highly aggressive, Harvard researchers reported this week.
The reduction in risk may also result from improved programs to provide emotional support for such men, a possibility that is reinforced by the observation that the suicide rate is higher in single men than in married ones. The risk of dying from cardiovascular disease was also elevated after prostate cancer diagnosis, the researchers reported in the Journal of the National Cancer Institute.
Dr. Fang Fang of Harvard University's Brigham and Women's Hospital in Boston and his colleagues used the government's SEER (Surveillance, Epidemiology and End Results) database to study 343,497 men with prostate cancer between 1979 and 2004. No cancer-free group was available to serve as a control group, and the team used published figures for expected deaths in the general population. During the period of the study, 148 of the men died from suicide and 6,845 died of cardiovascular disease. During the pre-PSA era up until 1993, men diagnosed with prostate cancer were 90% more likely to commit suicide in the first three months after diagnosis and 30% more likely in the first year, they found. After 1993, however, the suicide risk returned to normal. That contrasts with the same researchers' previous findings in Sweden that showed the risk of suicide there remained about 20% higher throughout the entire study period. The reason for this difference "is unclear," they wrote, but they suggest that the large number of indolent (nonaggressive) prostate cancers diagnosed during the later years and better access to emotional support may have lessened despair among patients, reducing suicide risk.
The risk of dying from heart disease in the United States was about doubled during the first month after diagnosis, but declined below normal during the seventh to twelfth months after diagnosis, creating a slightly increased risk of 9% for the entire year. The initial increase may be due to the stress of being diagnosed and to hormonal effects associated with the treatment. The reduction later could be a result of the fact that men who are tested for prostate cancer are more health-conscious and thus generally healthier than the general population. Alternatively, the diagnosis may have prompted them to alter their behaviors. Other studies have shown, for example, that quitting smoking lowers the risk of heart attack after a few months.
The study emphasizes the importance of emotional counseling for newly diagnosed cancer patients, the authors wrote. It also adds to "the increasingly complex scenario of pros and cons of extensive PSA testing, which entails detection of large numbers of nonlethal prostate cancers."
-- Thomas H. Maugh II