CHICAGO — Despite recommendations to the contrary, prostate-specific antigen screening is being performed in many elderly men who are not in good health and have limited life expectancies.
That conclusion was drawn from an analysis of data collected during a cohort study of 597,824 veterans aged 70 years and older who were seen at 104 Veterans Health Administration centers during fiscal years 2002 and 2003. The subjects did not have a history of prostate cancer, elevated prostate-specific antigen (PSA) levels, or prostate symptoms.
Most guidelines recommend that PSA screening should not be performed in elderly men who have a life expectancy of fewer than 10 years—the majority of those over age 80 years and men aged 70 years or older in poor health—because the known harms outweigh the potential benefits, Dr. Louise Walter and associates reported at the annual meeting of the American Geriatrics Society.
PSA levels are often inaccurate, leading to unnecessary biopsies because of false-positive results. This can cause psychological distress as well as treatment of irrelevant cancers, which may lead to incontinence or impotence. “The benefit of PSA screening remains unproven, and even if some benefit is ultimately proven, it is estimated that a life expectancy of 10–20 years would be needed for any chance of receiving such a survival benefit,” said Dr. Walter, of the geriatrics division at the University of California, San Francisco, and a staff physician at San Francisco VA Medical Center.
The mean age of the men in the VA-supported study was 77 years, and 333,041 (56%) had a PSA test performed in 2003. Health status was measured with the Charlson-Deyo index using VA and Medicare claims in 2002. The scores were used to stratify the men into three groups, ranging from best health (score of 0) to worst health (score of 4 or more).
PSA screening rates decreased significantly with advancing age, ranging from 64% in men aged 70–74 years to 27% in men aged 90 or older. But screening rates did not decline substantially with worsening health, she said. Among men aged 85–89 years, 36% in the best-health group had a PSA test, compared with 37% in the worst-health group.
Although men aged 80 years or older in the worst health have less than a 10% chance of living 10 years, 11,391 (41%) of these men had a PSA test.