Abstract 4344696: A nationwide survey of the association between the incidence of fatal ventricular arrhythmias and meteorological conditions in Japan

Background: The association between weather and incidence of fatal ventricular arrhythmia (FVA) has been investigated in small-scale studies, primarily involving patients with implantable cardioverter-defibrillators (ICDs). However, large-scale studies utilizing big data are currently limited. Hypothesis: Based on findings from earlier research, it was hypothesized that the incidence of FVA would be significantly influenced by weather conditions, with ambient temperature demonstrating a U-shaped relationship. Methods: The Japanese Registry Of All Cardiac and Vascular Diseases–Diagnosis Procedure Combination (JROAD-DPC) nationwide inpatient database (2012–2021), a comprehensive DPC-based registry encompassing nearly all acute-care hospitalizations across Japan, served as the primary data source for FVA patient analysis. Concurrently, daily meteorological data from the Japan Meteorological Agency (including average, maximum, and minimum temperatures, humidity, wind speed, and sunshine hours) were incorporated. Associations between FVA occurrence and weather parameters were investigated using univariable and multivariable logistic regression analyses. FVA incidence per 10 million population was determined after adjusting for the annual population of each prefecture, followed by the construction of cubic spline models for mean ambient temperature and FVA incidence. Results: A total of 5,897,719 cardiovascular disease patients were registered, of whom 73,315 experienced FVA. Among these FVA patients, the median age was 68.0 (55.0-77.0) years, and 74.0% of the patients were male. The incidence rates of ICDs, acute myocardial infarction (AMI), and out of hospital cardiac arrest were 2.9%, 12.0%, and 19.0%, respectively. In multivariable models, higher minimum temperature (adjusted odds ratio [OR] 1.110, 95% confidence interval [CI] 1.098–1.123), higher maximum temperature (OR 0.968, 95% CI 0.958–0.977) and higher average temperature (OR 0.945, 95%CI 0.931–0.967) were related to FVA risk. Spline curves showed a U-shaped pattern, with the lowest risk around 20°C, and both AMI-related FVA and non-AMI-related FVA showed similar spline curves. (Figure) Conclusion: This study is the first to comprehensively analyze the association between climate and the incidence of FVA in Japan, suggesting a U-shaped association between ambient temperature and the occurrence of FVA. This trend was similar across both AMI-related and non-AMI-related cases.