Dynamic changes in serum glutamine levels and clinical outcomes in acute ischemic stroke: a prospective analysis

Background: This is the first study to focus exclusively on a pure ischemic stroke cohort, exploring serum glutamine levels and their association with oxidative stress markers and clinical outcomes. Methods: 50 patients diagnosed with ischemic stroke were included in our study. We used methods such as LC-MS/MS to measure glutamine levels with high accuracy. Oxidative stress markers, including total antioxidant capacity (TAC) and total oxidant status (TOS), were also analyzed. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS), and functional outcomes were evaluated using the modified Rankin Scale (mRS) at 90 days. Results: Serum glutamine levels varied significantly based on stroke severity. Patients with NIHSS ≥16 demonstrated significantly lower glutamine levels compared to those with NIHSS <16. Dynamic changes in glutamine levels were observed, with levels decreasing between days 1 and 4 and increasing between days 4 and 10 . Patients undergoing therapeutic interventions (tPA or endovascular therapy) showed more stable glutamine levels compared to untreated patients (P = 0.028). Elevated TOS levels independently predicted mortality (hazard ratio [HR]: 2.34, 95% CI: 1.45–3.79, P = 0.002), while persistently low glutamine levels were associated with poor outcomes (HR: 0.89, 95% CI: 0.78–0.98, P = 0.03). Conclusion: The observed fluctuations in glutamine levels provide valuable insights into stroke severity, recovery, and mortality, suggesting their potential role in clinical prognosis. Our findings suggest that glutamine could play a critical role as a biomarker and therapeutic target in ischemic stroke, particularly in patients with NIHSS> 16.