Quality of care and in-hospital resource use in acute myocardial infarction: Evidence from Japan

Objectives: To determine the association between quality of care in process and outcome measures and in-hospital resource use among patients admitted for acute myocardial infarction (AMI) in Japan. Methods: We analyzed 23,512 AMI patients across 150 hospitals in Japan between April 2008 and March 2011. The exposure measure was inpatient hospital resource use, which was calculated from the sum of all hospital fees for healthcare services provided to AMI patients. Hospitals were then categorized into quartiles based on a risk-adjusted in-hospital resource use index. Quality of care was assessed using three process measures (in-hospital prescription of aspirin, β-blockers, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers) and two outcome measures (7-day and 30-day in-hospital mortality). Process and outcome measures were analyzed with multilevel logistic regression models that adjusted for patient and hospital characteristics. Results: No significant differences in process measures were observed across the quartiles of in-hospital resource use. In contrast, hospitals with the lowest resource use were significantly associated with poorer outcomes (7-day in-hospital mortality OR: 1.851 [95% CI 1.327-2.582]; 30-day in-hospital mortality OR: 1.706 [95% CI 1.259-2.312]) than hospitals with higher resource use. Conclusion: Poorer quality of care in outcome measures was significantly associated with lower resource utilization among AMI patients in Japanese hospitals, but process measures did not show similar associations.