Impact of population density on mortality in patients hospitalized for heart failure – JROAD-DPC Registry Analysis –

Abstract

Background: There is little evidence regarding social and geographic factors in patients with heart failure (HF). We sought to investigate the association between in-hospital mortality of patients with HF and population density of the patients' area of residence in Japan. Methods: The present study is a retrospective cohort analysis of the nationwide claim-based database, the Japanese Registry Of All cardiac and vascular Diseases-Diagnostic Procedure Combination (JROAD-DPC). We selected data of 196,286 hospitalized patients with HF (median age of 81 years and 51.8% males). Results: In-hospital mortality was 14.2%, 11.8%, and 9.5% in the lower, middle, and upper tertiles of population density, respectively. Age sub-analysis showed the largest absolute rural-urban disparity in mortality was 4.6% in the oldest subgroup (!80 years). Multivariate analysis using mixed logistic regression model revealed that higher population density was associated with lower in-hospital mortality: multivariable-adjusted odds ratio (OR): 0.785, 95% confidence interval (CI): (0.713-0.864), p < 0.001 and 0.687, 95% CI: (0.623-0.757), p < 0.001 in the middle and upper tertiles, in comparison with the lower tertile as a reference, after adjustment for age, sex, the New York Heart Association class, comorbidities, and hospital volume. The same tendency was observed in propensity score analysis using 62,291 (in the lower vs. middle tertile) and 57,228 (in the lower vs. upper tertile) matched pairs (OR: 0.797, 95% CI: 0.725-0.877, p < 0.001 and OR: 0.695, 95% CI: 0.634-0.762, p < 0.001 in the middle and upper tertile, respectively). Conclusions: Higher population density was associated with lower in-hospital mortality in HF. More research is needed to gain insight into causality.

Disease Management and Outcomes in Patients Hospitalized for Acute Heart Failure in Japan

“…Third, the high mortality rate may be due to the inclusion of hospitals not specialized in treating cardiovascular diseases. Evidence has shown that in-hospital mortality rates are lower in hospitals with a large number of subspecialty departments [ 30 ], in hospitals with more cardiologists per cardiovascular bed [ 16 ], and in areas with higher population density [ 17 ]. Furthermore, while there are no studies to date that have investigated differences in the implementation of the AHF guidelines between hospitals in Japan, evidence from other cardiology areas and countries indicates that such differences are likely [ 31 , 32 ].…”

“…A number of recent Japanese studies, such as registry-based studies [10], electronic medical records [EMR]/claims studies [13][14][15][16][17], and retrospective chart review studies [18], have investigated treatment patterns and/or outcomes during AHF hospitalizations in Japan. Nevertheless, gaps in knowledge remain.…”

Expected and observed in‐hospital mortality in heart failure patients before and during the COVID‐19 pandemic: Introduction of the machine learning‐based standardized mortality ratio at Helios hospitals

“…Since a similar trend also was apparent in 2019, a fixed regional effect caused by unknown structural differences is likely to influence the results. For example, population density has been shown to impact in‐hospital outcomes in HF patients 17 . An uneven distribution of cases discharged as hospital transfers between different areas could also contribute to this finding, as those cases were excluded from our analysis.…”

“…For example, population density has been shown to impact in-hospital outcomes in HF patients. 17 An uneven distribution of cases discharged as hospital transfers between different areas could also contribute to this finding, as those cases were excluded from our analysis. This was done to avoid a biased in-hospital death rate because no crosslinking of patient cases between hospitals was possible due to data structure and data privacy.…”

Characteristics of Discharged Elderly Patients with Acute Heart Failure Followed by Board-Certified-Cardiologists in a Rural Area of Japan

“…17) Because comorbidities, disabilities, and frailty are more com- mon in elderly patients with HF, 18,19) elderly outpatients with HF presenting NYHA functional class !III tended to be followed by general practitioners rather than by cardiologists in Europe. 20,21) Similar to Europe, a Japanese nationwide questionnaire survey suggested cardiologists answered that the barriers to follow-up with cardiologists include the difficulty for HF patients to visit outpatient cardiology clinics because most HF patients are elderly and frail or have no caregivers. 22) The statement of the JCS suggested that comprehensive medical care by general physicians has become more critical as the severity of heart failure has progressed and the care by general physicians should be increasing for patients with more advanced HF stage.…”