Relationship between persistent atrial fibrillation in high-altitude regions and left atrial diameter, red cell distribution width, and NT-ProBNP: a retrospective case-control study

Objective This study aimed to examine the association of left atrial diameter (LAD), red cell distribution width (RDW-CV) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) with persistent atrial fibrillation (AF) in high-altitude. Methods In this retrospective study, a total of 4,244 patients diagnosed with persistent AF at Qinghai Province Cardiovascular and Cerebrovascular Disease Specialist Hospital between January 2019 and June 2021 were included in the AF group, and 883 healthy individuals were selected as the control group. Factors associated with AF were evaluated. The AF group was stratified into middle-altitude and high-altitude groups. Comparisons of cardiac structural parameters and hematological indicators were performed across ethnic and altitude groups. Results LAD, N-terminal pro-B-type natriuretic peptide (NT-proBNP), and the coefficient of variation of RDW (RDW-CV) were identified as independent factors associated with AF [odds ratio (OR), 95% confidence interval (CI) = 1.014–1.241, 1.002–1.010, 1.282–1.655; p < 0.05]. In the middle-altitude group, significant differences were observed among patients of Tibetan, Han, and Hui ethnicity in terms of NT-proBNP ( p < 0.05). In the high-altitude group, significant differences were found in RDW-CV ( p < 0.05). Among patients of Hui ethnicity with AF, difference in NT-proBNP was observed between middle- and high-altitude groups ( p < 0.05). Conclusion LAD, NT-proBNP, and RDW-CV were factors associated with AF. LAD has a consistent association on patients with atrial fibrillation across different altitudes and ethnic groups.