Fear of public reporting of mortality rates may explain why cardiologists in New York are less likely than cardiologists in Michigan to perform angioplasty and other percutaneous coronary interventions on higher risk patients, according to a new study in the June 7, 2005, issue of the Journal of the American College of Cardiology.
“While making accurate outcomes information accessible has the potential to improve health care, our study suggests that public reporting of outcome data might also have an unintended effect on case selection, leading to a tendency toward not intervening on higher risk patients. More studies will be needed to determine the full effect of public reporting on quality and access to care,” said Mauro Moscucci, M.D., F.A.C.C., at the University of Michigan Health System in Ann Arbor.
The researchers compared demographics, indications and outcomes of 11,374 patients included in a multicenter (eight hospitals) percutaneous coronary intervention (PCI) database in Michigan, where no public reporting is present, with 69,048 patients in a statewide (34 hospitals) PCI database in New York, where public reporting is present.
Patients in Michigan were almost twice as likely to die in the hospital following PCI as patients in New York. However, the patients in Michigan appeared to be sicker on average before undergoing the procedures. After adjusting for the differences in the patients, there was no statistically significant difference in hospital death rates between the two states.
“After risk adjustment with logistic regression modeling, the higher in-hospital mortality rate observed in Michigan was explained by the differences in co-morbidities and indications for PCI, thus consistent with the fact that ‘sicker’ patients or higher risk patients are intervened on in Michigan when compared to New York,” Dr. Moscucci said.
“The most obvious differences between the New York and Michigan registries were the differences in case mix and the presence or absence of public reporting. Although we do not have any direct proof, a case selection bias driven by the fear of public reporting of higher mortality rates in New York was one possible explanation for the observed differences in case mix and mortality rates,” he said.
The authors said their hypothesis is indirectly supported by the results of a recent survey in which four out of five interventional cardiologists in New York reported that public reporting influenced their treatment decisions and that patients who might benefit from angioplasty may not receive the procedure as a result of public reporting.
Dr. Moscucci said that overall heart disease death rates are similar in Michigan and New York, making it unlikely that patients in general are sicker in Michigan, thus supporting the idea that the differences come from how cardiologists select which patients to treat with PCI.
“In addition, our analysis argues that quality-controlled clinical data with appropriate risk adjustment for demographics, comorbidities and treatment variables is necessary for meaningful outcomes information. It also supports the hypothesis that appropriate risk adjustment can account for significantly different mortality rates, such as the two-fold difference in this study,” Dr. Moscucci said.
However, the authors wrote, public report cards are often developed without adequate risk adjustment or use claims data that lack sufficient detail to perform a thorough risk adjustment.
In an editorial in the journal, Zoltan G. Turi, M.D., F.A.C.C., at the Robert Wood Johnson Medical School in Camden, N.J., wrote that the results of this study suggest that many physicians in New York may be shying away from aggressive treatment of higher risk patients in order to protect their report card grades.
“We do, as a matter of principle, want more information rather than less, and patients already suffer from a sense of disenfranchisement in choosing their physicians. Unfortunately, in the case of public reporting, information may well be misinformation, and what was intended to be helpful may be harmful,” Dr. Turi said.
Dr. Turi said current methods for risk adjustment are inadequate and that the system in New York may be “gamed” by some practitioners and hospitals seeking better grades on their report cards. He noted that overall improvements in quality in New York since public reports cards were introduced are similar to improvements seen in states that do not have public reporting. This suggests the improvements are linked to other measures.
“The public benefits from knowing, but not from knowing data that are incomplete and misleading, which is what public reporting as it stands does. Fixing that is extremely difficult and has not been successfully addressed despite much effort. Although instituted out of good intentions, public reporting appears to be an example of unanticipated negative results originating from a worthy idea,” Dr. Turi said.
Barry F. Uretsky, M.D., F.A.C.C., at the University of Texas Medical Branch in Galveston, Texas, who was not connected with this study, said it points out that the differences in outcomes in PCI between New York and Michigan appear to be related to the case mix.
“Why is there a difference? The authors suggest it may be due to the public database that New York has in place and physician concerns about it. Such a hypothesis cannot be proven by this article, but it is provocative. The article opens as many questions as it answers,” Dr. Uretsky said.
The American College of Cardiology, a 31,000-member nonprofit professional medical society and teaching institution, is dedicated to fostering optimal cardiovascular care and disease prevention through professional education, promotion of research, leadership in the development of standards and guidelines, and the formulation of health care policy.