When payment systems collide: the effect of hospitalization on anemia in renal dialysis patients.

Background: Different types of providers often face differing financial incentives for providing similar types of care. This may have implications for payment systems that target improvements in care requiring multiple types of providers.

Objectives: The objective of this study was to determine how hospitalization influences the anemia of Medicare patients with chronic renal failure, where anemia is treated under a prospective payment system during hospitalizations and under a fee-for-service system during outpatient renal dialysis.

Methods: We examined the effects of time in hospital and reason for hospitalization on levels of anemia among 87,263 Medicare renal dialysis patients with a hospital stay of 3 days or more during 2004. Medicare claims were used to measure changes in hematocrit between the month before and the month after hospital discharge, and to classify admissions with a high risk of anemia. Multilevel models were used to study variation in outcomes across providers.

Results: Longer time in the hospital was associated with worsening anemia. As expected, larger declines in hematocrit occurred following admissions for conditions or procedures with a high risk of anemia. However, we observed a similar effect of time in the hospital for admissions both with and without a high risk of anemia. There were relatively large differences in anemia outcomes across both individual hospitals and physicians.

Conclusions: Hospitalization-related anemia increases the need for care by outpatient renal dialysis providers. Efforts to improve care through payment system design are more likely to be successful if financial incentives are aligned across care settings.