Association of hemoglobin glycation index with all-cause mortality in critically ill patients with atrial fibrillation: a retrospective analysis from MIMIC-IV
摘要
Atrial fibrillation (AF) is recognized as the most prevalent sustained cardiac arrhythmia encountered in clinical practice, particularly among critically ill patients, and is correlated with heightened mortality rates. The hemoglobin glycation index (HGI), which captures interindividual variability in hemoglobin glycation, has emerged as a promising metabolic marker with potential prognostic significance. Nonetheless, the relationship between HGI and mortality in critically ill patients with AF remains to be elucidated.
MethodsThis retrospective cohort study utilized the MIMIC-IV database (version 3.1) and included 3,157 critically ill patients with AF. Patients were stratified into tertiles based on HGI levels: T1 (≤-0.505), T2 (-0.505 to 0.035), and T3 (> 0.035). Kaplan-Meier survival curves were constructed to compare mortality rates between groups. Cox proportional hazards regression models were employed to assess the relationship between HGI and all-cause mortality at 30, 90, 180, and 365 days. Threshold analysis was performed to identify optimal HGI cut-off values for mortality prediction. Restricted cubic spline regression was used to evaluate non-linear associations, complemented by subgroup and mediation analyses.
ResultsIn a cohort of 3,157 critically ill patients with atrial fibrillation (mean age 68.5 ± 8.9 years; 66.8% male), Kaplan-Meier analysis demonstrated a significantly elevated all-cause mortality at all time points for patients with lower hemoglobin glycation index (HGI) levels (log-rank P < 0.01). Multivariate Cox regression analysis indicated that the lowest HGI tertile was independently associated with an increased risk of mortality: 30-day (HR = 1.50, 95%CI: 1.08–2.08), 90-day (HR = 1.52, 95%CI: 1.15–2.02), 180-day (HR = 1.53, 95%CI: 1.18–1.98), and 365-day (HR = 1.44, 95%CI: 1.14–1.82). Restricted cubic spline analysis revealed an L-shaped relationship with inflection points at -0.255 (30-day), -0.435 (90-day), -0.435 (180-day), and − 0.475 (365-day). patients with HGI values exceeding these thresholds were associated with approximately 30% lower mortality risk at the corresponding time points. Subgroup analyses identified a significant interaction by gender, with females exhibiting a higher mortality risk than males when HGI was low, and the nonlinear association was more pronounced in females. Mediation analysis suggested that the estimated glomerular filtration rate (eGFR) partially mediated the relationship between HGI and mortality.
ConclusionIn patients with atrial fibrillation admitted to the intensive care unit, a low HGI was independently correlated with elevated risks of mortality at 30, 90, 180, and 365 days, exhibiting a pronounced L-shaped pattern and a significant interaction with gender. This association is partially mediated by renal function. HGI shows potential for improved risk stratification in this patient population.