Meteorological Influence on Atrial Fibrillation and Flutter: A Nationwide Observational Study in South Korea (2010–2022)

Background and rationale The impact of meteorological factors, including atmospheric temperature, humidity, and wind speed, on the incidence of atrial fibrillation and flutter (AF) has been the subject of several studies, but the findings have been inconsistent. Given the complex and multifaceted nature of this relationship, a larger-scale study was necessary to provide sufficient statistical power and elucidate potential associations between them. The aim of this study was, thus, to investigate the potential associations between meteorological factors and the incidence of AF. Methods The South Korean government provides open access to national health insurance and weather data for its citizens; the data was available from January 2010 to July 2022. The national health insurance data includes the monthly number of patients diagnosed with a specific condition, reflecting the incidence and prevalence of the condition. Pearson correlation analyses were performed using the statistical analysis software, SAS® OnDemand for Academics (SAS Institute Inc., Cary, North Carolina, United States), to examine the association between each month's national average climate data and the number of patients diagnosed with AF. Results The number of patients diagnosed with AF in the total population showed a statistically significant correlation only with average wind speed (correlation coefficient (r)=-0.42, 95%CI -0.55 to -0.28, p<0.001) and sunshine duration (r=0.27, 95%CI 0.12 to 0.41, p<0.001). Among females aged 20-24 years, there was a statistically significant association with other variables, including average temperature, precipitation, humidity, and atmospheric pressure (p<0.05). Diurnal temperature variation showed inconsistent associations across different age and sex groups. Conclusion The number of patients diagnosed with AF is negatively correlated with average wind speed and positively correlated with sunshine duration in the general population, particularly among the elderly. There was no significant association between the number of patients diagnosed with AF and average temperature, precipitation, or humidity, except for females aged 20-24 years, who exhibited a significant association with these variables. However, it is important to note that these correlations do not establish causality.