Background The JROAD-DPC (Japanese Registry of All Cardiac and Vascular Diseases Diagnosis Procedure Combination) is a nationwide claims database comprised of the Japanese DPC /Per Diem Payment System. This study aimed to investigate the relationship between prescription rates of guideline-directed medications in each hospital and in-hospital mortality among patients with acute myocardial infarction. Methods and Results A total of 61 838 Japanese patients from 741 hospitals with acute myocardial infarction between 2012 and 2013 were enrolled. The relationship between prescription rates of 4 guideline-directed medications for acute myocardial infarction and in-hospital mortality was analyzed. There were variations in the prescription ratio of β-blockers on admission (median prescription rate 23% [interquartile range 11% to 38%]) and at discharge (51% [36% to 63%]), and of angiotensin converting enzyme/receptor blocker (60% [47% to 70%]). The highest prescription rate quartile of each medication was associated with a significantly lower mortality compared with the lowest prescription rate quartile (aspirin on admission, incidence rate ratio 0.67 [95% CI 0.61-0.74], P<0.001; aspirin at discharge, incidence rate ratio 0.50 [95% CI 0.46-0.55], P<0.001; β-blocker on admission, 0.83 [0.76-0.92], P<0.001; β-blocker at discharge, 0.78 [0.71-0.85], P<0.001; angiotensin converting enzyme/receptor blocker, 0.68 [0.62-0.75], P<0.001; statin, 0.63 [0.57-0.70], P<0.001). The composite prescription score was inversely associated with in-hospital mortality (β coefficient=-0.48, P<0.001) and was closer to the plateau in the high-score range (median mortality for composite prescription scores of 6, 15, and 24 were 10.6%, 6.8%, and 4.6%, respectively). Conclusions The prescription rates of guideline-directed medications for treatment of Japanese acute myocardial infarction patients were inversely associated with in-hospital mortality.
Keywords: acute myocardial infarction; medication; quality indicators.