Certificate of Need (CON) for cardiac care: controversy over the contributions of CON.

Policy makers and providers seek to insure provision of high-quality health care while restraining cost growth. Many states pursue these two goals by enforcing Certificate of Need (CON) regulations, which require hospitals to obtain approval from a designated state agency before installing additional capacity or offering especially costly services. Federal law required that all states maintain CON for cardiac care in 1978. These regulations expired in 1986, leading many states to discontinue cardiac CON in the mid-1980s. This study tests whether presence of cardiac CON regulations is associated with lower mortality or differences in the number of cardiac procedures performed in a state. Past studies reached conflicting conclusions on the effects of cardiac CON. A study by Vaughan-Sarrazin et al. (VS) found that the risk-adjusted odds of death for Medicare patients who received coronary artery bypass graft surgery (CABG) between 1994 and 1999 was 22 percent higher in states without CON for open heart surgery versus states with CON (p<.001) (Vaughan-Sarrazin et al. 2002). The authors hypothesize that CON restricts the number of health care providers, leading to higher hospital procedure volume. Higher CABG volume has been associated with lower mortality rates in previous studies (Showstack et al. 1987; Hannan et al. 1989). In contrast, an analysis by DiSesa et al. (DS) using cardiac registry data from 2000 to 2003 found no significant difference in risk-adjusted mortality for CABG patients in states with and without CON (DiSesa et al. 2006). Another study by Ho using hospital discharge abstracts for 1989–2000 from the Nationwide Inpatient Sample collected by AHRQ HCUP found a significant association between inpatient mortality and CON status for CABG, but the magnitude of the effect was much smaller than that identified by VS (Ho 2007). The analyses conducted by VS and DS attribute any unexplained difference in risk-adjusted mortality between states with and without CON to the impact of the regulations. However, the differential may be due to state-level factors that influence outcomes through mechanisms unrelated to CON (DiSesa et al. 2006). DS conduct subanalyses adding state random effects to the regressions, which account for some unobserved heterogeneity, but not all types. Ho reduces concerns regarding state-level heterogeneity by estimating fixed effect regressions, which allow one to measure within-hospital changes in mortality associated with each year after which cardiac CON regulations were removed in a state. However, Ho's estimates mix mortality changes for states that dropped CON in the mid-1980s with those of states that dropped cardiac CON regulations more recently. If technology for cardiac surgery has improved over time, then the blending of mortality changes that resulted after CON removal, but along different points of the technology continuum, may yield misleading results. This paper compares the experience within states, before and after removal of cardiac CON regulations, yielding an estimate of the effects of CON, which is less subject to between-state heterogeneity concerns. We compare changes in patient mortality and the delivery of CABG and percutaneous coronary interventions (PCI) over time for states that dropped CON with states that maintained CON throughout the sample period. In doing so, we are better able to control for changes in patient mortality, which are contemporaneous with the removal of CON but unrelated to the regulations. By limiting the analysis to states that dropped cardiac CON most recently, we avoid concerns regarding the blending of estimates of the effects of CON regulations from different time periods. The results have important implications for regulators, who are concerned about the advantages and disadvantages of CON regulation.