The relationship between HbA1c and the functional outcome of acute ischemic stroke: A prospective cohort study

Background: High fasting blood sugar (FBS), hemoglobin A1C (HbA1c), and random glucose levels have been associated with poor neurological outcomes in patients with acute ischemic stroke (AIS). This study aimed to determine the prognostic value of HbA1c in predicting stroke's functional outcome. Methods: In this prospective cohort study, one-hundred patients with AIS who were admitted to the Imam Khomeini Hospital Complex, Tehran, Iran, from March 2019 to February 2020, within 72 hours of symptom onset were included. A 3-month modified Rankin Scale (mRS) was used to assess the functional outcome. Patients were divided into 3 groups based on the HbA1c levels: low HbA1c level (≤ 5.6%), moderate HbA1c level (5.7%-6.4%), and high HbA1c level (≥ 6.5%). Using chi-square test, t-test, analysis of variance (ANOVA), multiple logistic regression, and receiver operating characteristic (ROC) analysis, we studied the association and prognostic value of HbA1c levels and 3-month mRS as an outcome. The significance level was considered as P < 0.05. Results: We included 100 patients (53 men) with a mean age of 71.55 ± 11.94 years. The mean HbA1c, National Institutes of Health Stroke Scale (NIHSS), and mRS scores at admission were 6.98 ± 2.34, 8.27 ± 4.40, and 3.01 ± 1.47, respectively. Three-month mRS scores were significantly higher in patients with high HbA1c levels (3.43 ± 1.88) compared with low HbA1c levels (0.43 ± 0.61) and moderate HbA1c levels (1.72 ± 1.45) (P < 0.001). ROC analysis showed an area under the curve (AUC) of 0.897, and a serum HbA1c level at admission threshold of 6.15% had a sensitivity of 95.2% and a specificity of 77.6% to predict the poor outcome [95% confidence interval (CI): 0.837-0.957]. Conclusion: Our findings indicated that serum HbA1c levels at admission could be a valuable predictor of the functional outcome of patients with AIS.