Key Differences in Heart Failure Management, Outcomes Between US and Japan

Researchers have found clear differences in heart failure management and outcomes between the US and Japan. Most notably, patients with heart failure in Japan had significantly longer hospital stays compared with patients in the US, with a median of 18 days vs 5 days, respectively.

These findings were published in ESC Heart Failure and are based on data from more than 120,000 US patients on Medicare as well as more than 11,000 patients from the Japanese Registry of Acute Decompensated Heart Failure (JROADHF).¹ All patients were aged older than 65 years, with similar age and sex distributions in each country.

The study showed that US patients on Medicare had higher rates of implantable cardioverter defibrillator or cardiac resynchronization therapy during hospitalization (1.32%) than patients from the JROADHF (0.6%). However, patients in Japan were more likely to receive cardiovascular medications at discharge and undergo cardiac rehabilitation within 3 months of admission (31% vs 1.6%) and had higher rates of 30-day physician follow-up (77% vs 57%) compared with patients in the US.

Patients in the US had more frequent cardiovascular readmissions compared with patients in Japan at 30 and 180 days after hospital discharge | Image credit: Oleksii – stock.adobe.com

Cardiovascular readmission, cardiovascular mortality, and all-cause mortality were 2.1 to 3.7 times higher in US patients compared with Japanese patients. Specifically, all-cause mortality occurred in 38% and 65% of US patients at 1 and 3 years after hospitalization, respectively, compared with 25% and 46% of Japanese patients. This trend was similar for cardiovascular mortality, which occurred in 25% and 44% of Medicare patients and in 16% and 27% of JROADHF patients at 1 and 3 years, respectively. This gap in long-term mortality remained after adjusting for patient demographics, comorbidities, cardiovascular medications prior to hospitalization, and heart failure phenotypes.

According to the authors, this gap is likely due to several factors, including that US patients may have presented with more severe heart failure and comorbid conditions, as the dataset did not capture all severity measures. Differences in management may also explain the gap, as Japan had more timely titration of guideline-directed medical therapy, earlier initiation of cardiac rehabilitation, and better physician follow-up. Additionally, socioeconomic disparities in the US such as income status and race could have compounded barriers to care and lifestyle-related risk factors, contributing to the persistent difference in outcomes between the 2 countries.

Medicare recipients also had more frequent cardiovascular readmissions compared with JROADHF patients at 30 days (11% vs 7%) and 180 days (34% vs 17%) after hospital discharge.

In subgroup analyses of heart failure types, the authors observed similar patterns of comorbidities, except for a slightly higher rate of atrial fibrillation among Japanese patients with heart failure with preserved ejection fraction (HFpEF; 52%) compared with US Medicare patients with HFpEF (49%).

In comparing heart failure with reduced ejection fraction (HFrEF) and HFpEF groups within each country, the prevalence of atrial fibrillation, chronic kidney disease, and valvular heart disease was similar in Medicare patients at 12%, about 36%, and 49%, respectively. However, Japanese patients had notable differences in prevalence between HFrEF and HFpEF cohorts for atrial fibrillation (40% vs 52%), chronic kidney disease (43% vs 38%), and valvular heart disease (35% vs 43%). Within each heart failure phenotype, mortality and cardiovascular readmission rates were still notably higher in the Medicare cohort compared with the Japanese cohort. Patients with HFrEF had slightly worse outcomes compared with those with HFpEF in both Medicare and Japanese cohorts.

A comparison of hospitalization costs also revealed a significantly lower per-day cost of heart failure hospitalization in Japan ($516) compared with the US ($1323). This aligned with past research showing that US health care spending as a percentage of Gross Domestic Product was twice as high as Japan’s, and while it’s impossible to precisely compare health care costs between the 2 different currencies and economies, the authors suggested a number of potential reasons for this difference.

“First, unlike in the United States, health care prices in Japan are set and revised on an item-by-item basis every 2 years in order to manage total healthcare expenditures,” the authors noted, citing a 2019 US Ways and Means Committee report showing the average drug price in Japan was 85% lower than the price of a comparable drug in the US. “Second, physician salaries are substantially higher in the United States than in Japan, potentially contributing to higher costs for services and procedures in the United States.”

According to the authors, the observation of a longer length of stay for patients in Japan than the US has been noted in previous studies, and this discrepancy is attributed to differences in health care payment systems and associated financial incentives.²

In Japan, the Diagnosis Procedure Combination/Per-Diem Payment System (DPC/PDPS) differs from the Diagnosis-Related Group/Prospective Payment System (DRG/PPS) used in the US. Japan’s DPC/PDPS provides inclusive payments based on diagnoses, procedures, and length of stay, rather than a per-episode basis as in the DRG/PPS. Because of this, the DPC/PDPS offers weaker incentives to shorten hospital stays in comparison. This may partly explain the higher percentage of Japanese patients receiving heart failure medications and inpatient cardiac rehabilitation, as longer hospital stays allow more time for medication adjustments and rehabilitation programs. Additionally, an international trial found that countries with longer lengths of stay had lower rates of readmission within 30 days after heart failure hospitalization.

“These findings underscore the need for further investigation to elucidate the optimal length of hospitalization, evaluate the potential advantages of inpatient CR [cardiac rehabilitation] and enhance medication adherence and follow-up rates,” the authors concluded. “Additionally, especially in the United States, efforts should be directed towards mitigating disparities in socio-economic status that contribute to discrepancies in healthcare access and quality.”

References

1. Bates BA, Enzan N, Tohyama T, et al. Management and outcomes of heart failure hospitalization among older adults in the United States and Japan. ESC Heart Fail. Published online July 8, 2024. doi:10.1002/ehf2.14873
2. Konishi M, Ishida J, Springer J, et al. Heart failure epidemiology and novel treatments in Japan: facts and numbers. ESC Heart Fail. 2016;3(3):145-151. doi:10.1002/ehf2.12103