Dynamic changes in growth factor levels over a 7-day period predict the functional outcomes of traumatic brain injury

Traumatic brain injury (TBI) can result in poor functional outcomes and death, and overall outcomes are varied. Growth factors, such as angiopoietin-1 (Ang-1), vascular endothelial growth factor (VEGF), and granulocyte-colony stimulating factor (G-CSF), play important roles in the neurological functions. This study investigated the relationship between serum growth factor levels and long-term outcomes after TBI. Blood samples from 55 patients were collected at 1, 3 and 7 days after TBI. Blood samples from 39 healthy controls were collected as a control group. Serum Ang-1, G-CSF, and VEGF levels were measured using ELISA. Patients were monitored for 3 months using the Glasgow Outcome Scale-Extended (GOSE). Patients having a GOSE score of > 5 at 3 months were categorized as a good outcome, and patients with a GOSE score of 1-5 were categorized as a bad outcome. Our data demonstrated that TBI patients showed significantly increased growth factor levels within 7 days compared with healthy controls. Serum levels of Ang-1 at 1 and 7 days and G-CSF levels at 7 days were significantly higher in patients with good outcomes than in patients with poor outcomes. VEGF levels at 7 days were remarkably higher in patients with poor outcomes than in patients with good outcomes. Receiver operating characteristic analysis showed that the best cut-off points of serum growth factor levels at 7 days to predict functional outcome were 1,333 pg/mL for VEGF, 447.2 pg/mL for G-CSF, and 90.6 ng/mL for Ang-1. These data suggest that patients with elevated levels of serum Ang-1, G-CSF, and decreased VEGF levels had a better prognosis in the acute phase of TBI (within 7 days). This study was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR1800018251) on September 7, 2018.