Diagnostic and prognostic value of serum neurogranin level in patients with acute ischemic stroke

OBJECTIVE AND HYPOTHESIS: Despite all the developments in modern medicine, stroke continues to be a serious cause of disability and death all over the world. Ischemic stroke is the most common type. Neurogranin (Ng) is a postsynaptic protein expressed in the brain, particularly in spinous ridges in dendrites. Limited literature reports show that Ng level changes statistically in cases of acute central nervous system injury. Acute ischemic stroke (AIS) has not been adequately studied among the regarding studies. In this study, we aimed to evaluate the clinical use of Ng as a diagnostic and prognostic biomarker by comparing serum Ng levels in AIS patients with healthy individuals. METHODS: The study consisted of 86 patients who admitted to Yozgat Bozok University Emergency Department and were diagnosed with AIS, and 55 control participants. Serum Ng levels were measured with ELISA technique and data between groups were compared. A p value ˂ 0.05 was considered for statistical significance. RESULTS: A total of 141 participants, 86 of whom were AIS patients and 55 controls, were included in the study. While 48.8% (n = 42) of the patients in the study group were male, 51.2% (n = 44) were female, 41.8% (n = 23) of the control group was male, while 58.2% of which (n = 32) were women. The mean age was 69.15 ± 11.86 in the patient group and 61.24 ± 9.87 in the control group. The patient group and control group were statistically similar in terms of gender, age and comorbid chronic diseases. While the mean serum Ng level of the patient group was 155.38 ± 51.47 ng/mL, the serum Ng level of the control group was 104.45 ± 56.47 ng/mL, with a statistically significant difference (p ˂ 0.001). The ideal serum Ng cut-off value for the first 24-hour acute period diagnosis of AIS was determined as 122.92 ng/mL (AUC: 0.717, Sen: 66.3%, Spe: 65.5%) by ROC analysis. The serum Ng level of 25 patients who were in hyperacute phase of AIS within the first 6 hours was measured as 183.35 ± 36.15 ng/mL, while the number of patients admitted between 6-24 hours was 61, and the serum Ng level was 143.92 ± 52 ng/mL. The serum Ng cut-off value for 25 patients admitted within the first 6 hours from the onset of ischemic stroke was determined as 160.13 ng/mL (AUC:0.868, Sen:84.0%, Spe:83.6%) by ROC analysis. While the serum Ng level of 19 patients who admitted during the first 4.5 hours, which is the appropriate window for thrombolytic therapy candidates, was found to be 186.78 ± 38.00 ng/mL, The diagnostic performance of the Ng level was found to be similar to the performance for the first 6 hours (AUC: 0.874). However, serum neurogranin levels were not found to be correlated with ischemic infarct volume, 6-month modified Rankin Scale score, and 6-month mortality in acute ischemic stroke (p = 0.218, 0.893, and 0.585, respectively). CONCLUSION: This is the first study to evaluate the diagnostic and prognostic clinical use of acute ischemic stroke patients by comparing serum Ng levels with the control group. Serum Ng level was found to be significantly higher in acute ischemic stroke patients compared to the controls. Serum Ng level is quite successful in predicting the diagnosis of acute ischemic stroke. However, its benefit in terms of ischemic infarct volume and long-term morbidity and mortality could not be demonstrated. Keywords: Acute Ischemic Stroke, Neurogranin, Biomarker