The Role of Serum Secretoneurin Levels in Patients with Traumatic Brain Injury

Background: Secretoneurin is a neuropeptide expressed from endocrine, neuroendocrine, and neural tissues. Our study aimed to investigate whether there was a relationship between secretoneurin levels and the severity of traumatic brain injury (TBI). Methods: Ninety patients aged over 18 years who were admitted to the emergency department with head trauma between April 2020 and October 2020 and 20 healthy volunteers (control group) were included in the study. Patients were divided into three groups according to Glasgow Coma Scale scores: Mild TBI (n=33), moderate TBI (n=28), and severe TBI (n=29). The final status of the patients was evaluated in three groups: exitus, discharge with Glasgow Outcome Scale (GOS) ≤ 3 and discharge with GOS >3. Results: The median secretoneurin levels of patients with severe TBI 31.71 (14.21-70.95) were found to be significantly higher than in those with moderate TBI [17.30 (10.71-69.27) (P=0.025), and patients with moderate TBI had a substantially higher level of secretoneurin than those with mild TBI 11.70 (6-16.25) (P<0.001). There was no statistically significant difference between the median secretoneurin levels in patients with mild TBI and the control group 10.73 (5.33-13.18) (P=0.999). The secretoneurin cut-off value of >18.13 ng/mL had a sensitivity of 83.87% and a specificity of 77.97% for poor neurologic outcomes (AUC 0.86, 95% CI: 0.77- 0.92). The secretoneurin cut-off value of >20.67 ng/mL had a sensitivity of 90.91% and a specificity of 74.68% for mortality (AUC 0.85, 95% CI: 0.76-0.92). Conclusion: Secretoneurin can be a useful biomarker in diagnosing patients with moderate-tosevere TBI. It may also guide physicians in predicting the clinical outcome of patients with TBI.