Association Between Registered Instructors of Cardiac Rehabilitation and Inpatient Cardiac Rehabilitation Participation in Japan: A Nationwide 10-Year Analysis.

Background: There have been no reports examining whether Registered Instructors of Cardiac Rehabilitation (RICRs) contribute to inpatient cardiac rehabilitation (CR) participation. Methods and Results: Using data from the Japanese Registry of All Cardiac and Vascular Diseases and the Diagnosis Procedure Combination (JROAD-DPC) database, we calculated the inpatient CR participation rate for each prefecture from 2014 to 2023. The number of RICRs, cardiologists, general hospital physicians, general hospital nurses, and physical therapists per 100,000 population were also calculated for each prefecture. The median CR participation rate increased from 31.2% to 57.3%, and the total number of RICRs increased from 3,399 to 7,367 during the study period. In prefecture-level correlation analyses for 2023, the number of RICRs was positively associated with the CR participation rate (r=0.31; 95% confidence interval 0.02, 0.55; P=0.03). In contrast, the increase in the number of RICRs was not significantly associated with the growth of CR participation during the study period. Conclusions: Regions with a greater number of RICRs consistently demonstrated higher levels of CR implementation; however, increases in the number of RICRs were not directly correlated with longitudinal growth in CR utilization.