Overall cardiovascular hospitalization rates were 1.5-fold higher and income-based disparities were much greater in the U.S. compared with Denmark among patients aged ≥65 years, according to a cross-sectional study published Feb. 5 in JAMA Cardiology.

Frederikke Held Berg, MSc, Rishi K. Wadhera, MD, et al., compared cardiovascular hospitalization rates and outcomes in patients in the U.S. and Denmark, two high-income countries with diverse health care systems, and the differences by income level in 2021. The U.S. cohort included 58,614,110 adults enrolled in Medicare (mean age, 74.6 years; 54.9% female). The Danish cohort included 1,176,542 adults (mean age, 75.3 years; 53.9% female) using nationwide data from Denmark's universal health care system.

Results show that 2.0% of the U.S. cohort vs. 1.4% of the Denmark cohort were hospitalized for a cardiovascular event.

The primary outcome was age- and sex-standardized hospitalization rates for myocardial infarction (MI), heart failure (HF) and ischemic stroke. Overall cardiovascular disease hospitalizations were higher in the U.S. than in Denmark (relative risk [RR], 1.50). Of note, the risk of hospitalization for HF was more than twofold higher in the U.S. than Denmark (RR, 2.37), the risk of hospitalization for MI was also higher in the U.S. (RR, 1.56), whereas the hospitalization for ischemic stroke was 10% lower in the U.S. (RR, 0.90). The overall 30-day all-cause mortality rate, a secondary outcome, was slightly higher in the U.S. compared with Denmark (RR, 1.12).

Income-based disparities existed in both countries. Overall U.S. cardiovascular hospitalization rates were more than twofold higher among low-income vs. higher-income older adults (RR, 2.38), while the magnitude of income-based disparities was smaller in Denmark (RR, 1.45). The authors write this may be due to the high level of income inequality in the U.S. compared with Denmark.

In an accompanying editorial comment, Sadiya S. Kahn, MD, MSc, FACC, notes that opportunities exist to improve the health of Americans. Kahn writes, however, that "this will require fundamental changes in the national approach to health care delivery with a greater focus on public health, preventive efforts, and health equity."