Nonlinear association between hemoglobin glycation index and mortality in ischemic stroke Patients: Insights from the MIMIC-IV database

Abstract

Aims: Hemoglobin glycation index (HGI) is closely associated with adverse outcomes in several diseases. However, few studies have investigated the correlation between HGI and prognosis in patients with critical ischemic stroke.

Methods: A cohort of patients was established from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Kaplan-Meier analysis, multivariate regression models, and restricted cubic splines (RCS) were used to investigate the associations between HGI and different outcomes. Mediation models were constructed to determine the mediating role of white blood cell (WBC) counts.

Results: This study included 2,332 participants. In-hospital mortality differs significantly across HGI groups (24.43 %, 11.82 %, and 10.14 %, P < 0.001). Multivariate regression analyses found that lower HGI was significantly associated with greater mortality risk. Nonlinear analyses revealed an L-shaped association between HGI and short-term mortality (30-day and in-hospital), while a reverse J-shaped relationship emerged for long-term (365-day) mortality. Mediation analysis revealed that WBC counts mediated the association with proportions (%) of 33.73, 19.65, and 30.00, respectively.

Conclusion: Lower HGI is consistently related to poorer outcomes in patients with critical ischemic stroke. Higher HGI could be a protective factor in the short term but might increase mortality risk in the long term. WBC counts significantly mediate the association.

Keywords: Hemoglobin glycation index; Ischemic stroke; MIMIC-IV database; Mediation analysis; Retrospective cohort study.