Variation in prostate-specific antigen screening in men aged 80 and older in fee-for-service Medicare.

OBJECTIVES: To determine the rate of prostate-specific antigen (PSA) screening in men aged 80 and older in Medicare and to examine geographic variation in screening rates across the U.S.
DESIGN: Retrospective cohort study of variation across hospital referral regions using administrative data.
SETTING: National random sample in fee-for-service Medicare. PARTICIPANTS: Medicare beneficiaries aged 80 and older in 2003. MEASUREMENTS: Percentage of men aged 80 and older screened using the PSA test.
RESULTS: The national rate of PSA screening in men aged 80 and older was 17.2%, but there was wide variation across regions (<2-38%). Higher PSA screening in a region was positively associated with greater total costs (correlation coefficient (r)=0.49, P<.001), greater intensive care unit use at the end of life (r=0.46, P<.001), and greater number of unique physicians seen (r=0.36, P<.001). PSA screening was negatively associated with proportion of beneficiaries using a primary care physician as opposed to a medical subspecialist for the predominance of ambulatory care (r=-0.38, P<.001).
CONCLUSION: PSA screening in men aged 80 and older is common practice, although its frequency is highly variable across the United States. Its association with fragmented physician care and aggressive end-of-life care may reflect less reliance on primary care and consequent difficulty informing patients of the potential harms and low likelihood of benefit of this procedure.