Market Competition and Health Outcomes in Hemodialysis.

OBJECTIVE

To examine whether market competition is associated with improved health outcomes in hemodialysis.

DATA SOURCES

Secondary analysis of data from a national dialysis registry between 2001 and 2011.

STUDY DESIGN

We conducted one- and two-part linear regression models, using each hospital service area (HSA) as its own control, to examine the independent associations among market concentration and health outcomes.

DATA COLLECTION

We selected cohorts of patients receiving in-center hemodialysis in the United States at the start of each calendar year. We used information about dialysis facility ownership and the location where patients received dialysis to measure an index of market concentration-the Hirschman-Herfindahl Index (HHI)-for HSA and year, which ranges from near zero (perfect competition) to one (monopoly).

PRINCIPAL FINDINGS

An average reduction in HHI by 0.2 (one standard deviation in 2011) was associated with 2.9 fewer hospitalizations per 100 patient-years (95 percent CI, 0.4 to 5.4). If these findings were generalized to the entire in-center hemodialysis population, this would translate to 8,100 (95 percent CI 1,200 to 15,000) fewer hospitalizations in 2011. There was no association between change in market competition and mortality.

CONCLUSIONS

Market competition in dialysis may lead to improved health outcomes.