Background: Patients with diabetes mellitus and heart failure with reduced ejection fraction (HFrEF) are at high risk for morbidity and mortality. The treatment of these patients can be complex, with the recommended management of one disease often complicating the other. International assessments of the management of these patients are not available. We sought to compare the clinical characteristics and management of patients with diabetes and HFrEF in the US and Asia.
Methods: Data were obtained from the Diabetes Collaborative Registry (DCR), a US-based outpatient registry of adults with diabetes (2013-2016), and ASIAN-HF, a multi-national Asian registry of adults with HF (2010-2016). Patients with diabetes and HFrEF (defined as ejection fraction <40%) were included. As Asian countries represent a broad spectrum of economic development and healthcare infrastructure, countries were categorized into high (Asia-HI) vs. low income (Asia-LI), per United Nations classification. 
Results: Our analytic cohort included 51,992 patients with diabetes and HFrEF from the US, 1,075 from Asia-HI, and 1,160 from Asia-LI. Patients in the US were more likely to be older (US vs. Asia-HI vs. Asia-LI: 70.0 vs. 63.2 vs. 59.8 years), obese (body mass index: 30.8 vs. 25.6 vs. 25.5 kg/m2), current/former smokers (60.5% vs. 54.4% vs. 38.7%), and have known coronary disease (81.9% vs. 62.9% vs. 64.9%; p<0.001 for all). Patients in the US were more likely to have devices but were less likely to be on guideline recommended medical therapy for HFrEF (Table). Among patients with type 2 diabetes on glucose-lowering medications, patients in the US were less likely to be on sulfonylureas and more likely to be on insulin, thiazolidinediones, GLP-1 RAs, and SGLT2 inhibitors.
Conclusion: Significant differences exist between US and Asia in the clinical characteristics and treatment of patients with diabetes and coexisting HFrEF. Practice patterns are not optimal in either area, with opportunities for improvement in the use of evidence-based therapies for both conditions. Effective tools to guide medication choices for these complex and high-risk patients could have substantial impact on quality and outcomes.

Management of patients with diabetes and heart failure with reduced ejection fraction: A cross-country comparison