Objectives: The aim of this study was to explore the correlation between blood test indicators and Atrial Fibrillation (AF) in Individuals Aged 65 and Older in Yangzhou, Jiangsu.
Methods: From January 1, 2019, to August 31, 2023, an epidemiological cross-sectional survey was conducted among the elderly population undergoing health check-ups at Northern Jiangsu People's Hospital in Jiangsu Province. Patients diagnosed with AF after a 12-lead electrocardiogram were included in the case group, and non-AF individuals matched by age and gender in a 1:4 frequency ratio were included in the control group. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to select important variables from routine blood tests and biochemical indicators and their derived indicators (such as TyG, TyG-BMI, TG/HDL-c, RAR, NLR, MHR). Based on the selected variables, participants were divided into four groups (Q1 ~ Q4), and multifactorial Logistic regression analysis, restricted cubic spline regression, gender subgroup analysis and Receiver Operating Characteristic (ROC) curve were used to explore the relationship between the relevant variables and AF.
Results: A total of 5,879 elderly individuals over the age of 65 were included in the study, with a prevalence of AF of 2.96% (174/5,879). The prevalence of AF in the overall population, as well as in male and female populations, showed a continuous increasing trend with age (P for trend < 0.001). A total of 696 individuals without AF after matching served as the control group, and LASSO regression identified albumin, direct bilirubin, and uric acid as three significant indicators. After adjusting for relevant confounding factors, lower levels of albumin, and higher levels of direct bilirubin and uric acid were significantly associated with the occurrence of AF (P < 0.05). Gender subgroup analysis revealed that in the elderly female population, albumin was not significantly associated with AF (P > 0.05), while direct bilirubin and uric acid were significantly associated with AF (P < 0.05). In the male population, albumin, direct bilirubin, and uric acid were significantly associated with AF (P < 0.05). Restricted cubic spline regression analysis showed a significant nonlinear relationship between direct bilirubin and AF (P for nonlinear < 0.001). The ROC curve analysis indicates that albumin, direct bilirubin, and uric acid all have good association strength with AF in elderly patients, with direct bilirubin showing the strongest association effect (AUC (95% CI) = 0.728 (0.686, 0.769)).
Conclusions: Low levels of albumin, high levels of direct bilirubin, and uric acid are all significantly associated with AF in the elderly population of the Central Jiangsu region. The conclusions of this study need further validation with a larger sample size.
Keywords: Atrial fibrillation; Case-control study; Elderly population; Restricted cubic splines.
© 2025. The Author(s).