To investigate the predictive value of early detection of plasma phosphoglycerate kinase 1 (PGK1) on the severity and prognosis of patients with traumatic brain injury (TBI).

Sixty-eight TBI patients admitted to Neurosurgery Department of the Second Affiliated Hospital of Nantong University from August 2020 to May 2022 were prospectively collected and categorized into mild TBI group (GCS 13-15 points), moderate TBI group (GCS 9-12 points), and severe TBI group (GCS 3-8 points) based on the GCS score, and were divided into adverse group and good group based on the GOS score at 6 months after TBI. One hundred healthy medical checkups who were admitted to the hospital for medical checkups in the same period were selected as the control group. Plasma PGK1 and interleukin-6 (IL-6) levels were measured by enzyme-linked immunosorbent assay within 12 h after the patients' admission to the hospital. The differences in plasma PGK1 and IL-6 levels in each group were analyzed, and the relationship between the two and the severity and prognosis was analyzed by Pearson linear correlation.

Plasma PGK1 and IL-6 levels were significantly higher in the TBI group compared with the control group, with statistical significance (P<0.05). TBI patients were divided into mild TBI group (25 cases), moderate TBI group (22 cases), and severe TBI group (21 cases). The plasma PGK1 and IL-6 levels in the moderate TBI group were significantly higher than those in the mild TBI group, and the severe TBI group was also significantly higher than those in the moderate TBI group, with a statistically significant difference (P<0.05). Pearson linear correlation showed that the plasma PGK1 level was strongly negatively correlated with GCS score (r=-0.697); IL-6 level was strongly negatively correlated with GCS score (r=-0.633); the plasma PGK1 level was strongly negatively correlated with GOS score (r=-0.641); IL-6 level was moderately negatively correlated with GOS score (r=-0.565); the plasma PGK1 level was moderately positively correlated with IL-6 (r=0.437), and the differences were statistically significant (P<0.05). Plasma PGK1 concentrations had a less predictive value of patient severity and prognosis than GCS scores, but exceeded IL-6 (AUC values of GCS, PGK1 and IL-6 were 0.965, 0.812 and 0.769, P<0.001).

The plasma PGK1 level in TBI patients is significantly correlated with the severity and prognosis of brain injury, and is positively correlated with IL-6 level in plasma. The higher the levels of PGK1 and IL-6, the worse the condition and prognosis of TBI patients.