Hospital-Level Variation in Cardiac Rehabilitation After Myocardial Infarction in Japan During Fiscal Years 2014–2015 Using the National Database

Background: Cardiac rehabilitation (CR) is an evidence-based medical service for patients with acute myocardial infarction (AMI); however, its implementation is inadequate. We investigated the provision status and equality of CR by hospitals in Japan using a comprehensive nationwide claims database. Methods and Results: We analyzed data from the National Database of Health Insurance Claims and Specific Health Checkups in Japan for the period April 2014–March 2016. We identified patients aged ≥20 years with postintervention AMI. We calculated hospital-level proportions of inpatient and outpatient CR participation. The equality of hospital-level proportions of inpatient and outpatient CR participation was evaluated using the Gini coefficient. We included 35,298 patients from 813 hospitals for the analysis of inpatients and 33,328 patients from 799 hospitals for the analysis of outpatients. The median hospital-level proportions of inpatient and outpatient CR participation were 73.3% and 1.8%, respectively. The distribution of inpatient CR participation was bimodal; the Gini coefficients of inpatient and outpatient CR participation were 0.37 and 0.73, respectively. Although there were statistically significant differences in the hospital-level proportion of CR participation for several hospital factors, CR certification status for reimbursement was the only visually evident factor affecting the distribution of CR participation. Conclusions: The distributions of inpatient and outpatient CR participation by hospitals were suboptimal. Further research is warranted to determine future strategies.