Association between hemoglobin glycation index and poor prognosis in patients with AKI: a retrospective cohort analysis of the MIMIC-IV database.

BACKGROUND

There have been no investigations on the relationship between hemoglobin glycation index HGI) and poor prognosis in patients with acute kidney injury (AKI).

METHODS

Patients were enrolled from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. The HGI was calculated using a linear regression model fitted to glycosylated hemoglobin and fasting plasma glucose (FPG). Kaplan-Meier survival analysis and Cox proportional hazards regression analysis were performed based on HGI quartiles to determine the independent association between HGI and mortality risk. A restricted cubic spline (RCS) was employed to assess the potential nonlinear relationship between HGI and mortality risk. A two-piecewise linear regression model was developed to identify the threshold effect. Additionally, a linear regression model was applied to evaluate the association between HGI and the length of hospital stays.

RESULTS

A total of 3684 patients with AKI were included in this study. Among them, 486 patients died within 28 days, and 673 patients died within 90 days. Multivariate Cox regression analysis identified HGI as an independent risk factor for both 28-day mortality (hazard ratio [HR], 1.65 [95% CI 1.26 to 2.16],  < 0.001) and 90-day mortality (HR, 1.45 [95% CI 1.16 to 1.82],  < 0.001) in AKI. The RCS analysis revealed a significant L-shaped association between HGI and both 28-day (nonlinear  < 0.001) and 90-day mortality (nonlinear  < 0.001). For 28-day mortality, the inflection point was 1.09 (HR = 0.72, 95% CI: 0.65 to 0.805). For 90-day mortality, the inflection point was 1.14 (HR = 0.76, 95% CI: 0.69 to 0.84). Notably, the association between HGI and outcomes was more significant in nondiabetic patients ( < 0.05). Additionally, HGI was found to be significantly and inversely associated with the length of hospital stays.

CONCLUSION

In patients with AKI, a low HGI is an independent risk factor for 28-day and 90-day mortality, exhibiting an L-shaped association. HGI may serve as a potential predictor of mortality risk.