Identification of red cell distribution width trajectory patterns and their association with 28-day mortality in intensive care unit patients with atrial fibrillation: A latent class analysis

BackgroundRed cell distribution width (RDW) has been identified as a potential prognostic marker in multiple cardiovascular and critical illnesses. Nevertheless, its prognostic value, particularly regarding changes in RDW over time among patients with atrial fibrillation (AF), remains uncertain.MethodsA retrospective cohort study was conducted using data from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The study included adult intensive care unit (ICU) patients with AF who had at least three RDW measurements within the first 36 h of ICU admission. Latent growth mixture modeling (LGMM) was applied to identify distinct RDW progression patterns over time. The association between the identified RDW trajectory groups and 28-day mortality was assessed using Cox proportional hazard regression. Kaplan-Meier survival curves and subgroup analyses were also conducted.ResultsA total of 3509 patients were enrolled in the analysis. LGMM identified three distinct RDW trajectories: Class 1 (stable and low RDW), Class 2 (moderate with a rising RDW) and Class 3 (high with fluctuating RDW). After adjusting for demographics, clinical parameters, comorbidities and treatments, Class 2 remained independently associated with higher 28-day mortality compared with Class 1 (<i>P</i> = 0.003). No significant difference was observed between Class 3 and Class 1. Kaplan-Meier analysis confirmed significant differences in survival among the classes (<i>P</i> < 0.001). Subgroup analysis showed consistent associations without significant interactions.ConclusionRDW trajectory patterns are independently associated with 28-day mortality in critically ill AF patients and may serve as valuable prognostic indicators in this population.