Hospitalization for Heart Failure in the United States, UK, Taiwan, and Japan: An International Comparison of Administrative Health Records on 413,385 Individual Patients

•Previous reports evaluating international differences in characteristics and survival of patients hospitalized for heart failure are mainly from clinical trials and registries with small national samples and biased case-selection.•This study of nationally representative electronic health care records of more than 400,000 patients hospitalized for heart failure from 4 countries on 3 continents reveals marked variations in patient characteristics, health care resource use, and clinical outcomes.•A better understanding of these international variations may help in the translation of health care interventions from one country to another and in the design of international trials. Registries show international variations in the characteristics and outcome of patients with heart failure (HF), but national samples are rarely large, and case selection may be biased owing to enrolment in academic centers. National administrative datasets provide large samples with a low risk of bias. In this study, we compared the characteristics, health care resource use (HRU) and outcomes of patients with primary HF hospitalizations (HFH) using electronic health records (EHR) from 4 high-income countries (United States, UK, Taiwan, Japan) on 3 continents. We used electronic health record to identify unplanned HFH between 2012 and 2014. We identified 231,512, 10,991, 36,900, and 133,982 patients with a primary HFH from the United States, the UK, Taiwan, and Japan, respectively. HFH per 100,000 population was highest in the United States and lowest in Taiwan. Fewer patients in Taiwan and Japan were obese or had chronic kidney disease. The length of hospital stay was shortest in the United States (median 4 days) and longer in the UK, Taiwan, and Japan (medians of 7, 9, and 17 days, respectively). HRU during hospitalization was highest in Japan and lowest in UK. Crude and direct standardized in-hospital mortality was lowest in the United States (direct standardized rates 1.8, 95% confidence interval 1.7%–1.9%) and progressively higher in Taiwan (direct standardized rates 3.9, 95% CI 3.8%–4.1%), the UK (direct standardized rates 6.4, 95% CI 6.1%–6.7%), and Japan (direct standardized rates 6.7, 95% CI 6.6%–6.8%). The 30-day all-cause (25.8%) and HF (7.2%) readmissions were highest in the United States and lowest in Japan (11.9% and 5.1%, respectively). Marked international variations in patient characteristics, HRU, and clinical outcomes exist; understanding them might inform health ca