Targeting screening mammography according to life expectancy among women undergoing dialysis

Abstract

Background: Screening guidelines recommend that mammography be targeted to women likely to live longer than 5 years. Because women undergoing dialysis have a reduced but variable life expectancy, their appropriate use of screening is controversial. Therefore, we conducted this study to describe national mammography rates among women undergoing dialysis with differing prognostic factors and to determine whether screening is targeted to healthier women who live longer.

Methods: Using the US Renal Data System, we identified 17,090 women aged 50 years or older who started dialysis in 1997. We tracked women for 5 years to ascertain their use of screening mammography or death.

Results: The 5-year survival rate was 25%. The biennial screening mammography rate was 25%, ranging from 12% for women aged 80 years or older to 69% for women who were ever on the transplant list. Women who were screened in the past year had a lower death rate than those who were not (hazards ratio, 0.55; 95% confidence interval, 0.51-0.59). Yet, 2198 women (13%) who died within 5 years underwent screening, and 2004 women (12%) who lived more than 5 years while receiving dialysis did not undergo screening.

Conclusions: Screening mammography rates are appropriately low among women undergoing dialysis because the 5-year survival rate is low. Screening is being targeted to women who are healthier and live longer. However, targeting could be improved by increasing screening in the few women undergoing dialysis with substantial life expectancies while decreasing screening in most women undergoing dialysis who live less than 5 years.