Synergistic mortality risk of glycemic and blood pressure variability in critical stroke: A retrospective cohort study from the MIMIC-IV database

Variability in glycemic (GV) and systolic blood pressure (SBPV) are independent risk factors for adverse outcomes in stroke. However, their combined impact on mortality in stroke patients requiring intensive care remains unclear. This study aimed to evaluate the individual and additive effects of short-term GV and SBPV on mortality in critically ill stroke patients. We retrospectively analyzed hemorrhagic and ischemic stroke patients from the Medical Information Mart for Intensive Care IV database. GV and SBPV were calculated as the coefficient of variation from all glucose and systolic blood pressure measurements within the first 72 hours of intensive care unit admission. High variability was defined as the highest tertile. The additive effect was assessed by the number of high-variability parameters and a composite variability score (0-4). The study included 2659 hemorrhagic and 3606 ischemic stroke patients. After full adjustment, the highest GV tertile was associated with significantly increased 28-day mortality (Hemorrhagic: hazard ratio [HR] = 1.84, 95% confidence interval [CI] 1.38-2.44; Ischemic: HR = 1.35, 95% CI 1.08-1.70). Similarly, the highest SBPV tertile was associated with higher mortality (Ischemic: HR = 1.67, 95% CI 1.35-2.06). Most importantly, patients with both high GV and high SBPV had the most significant risk, with adjusted HRs of 2.51 (95% CI 1.89-3.33) for 28-day mortality in hemorrhagic stroke and 2.01 (95% CI 1.57-2.58) in ischemic stroke. A graded, dose-response relationship was observed between increasing variability score and mortality risk (P for trend < .001). Short-term GV and SBPV during intensive care unit stay are independent and additive predictors of mortality in critically ill stroke patients. Stabilizing these parameters may be a potential therapeutic target to improve outcomes.