Usefulness of serum glucose and potassium ratio as a predictor for 30-day death among patients with severe traumatic brain injury

Background: Serum glucose and potassium ratio (GPR) was recently found to be related to outcome of aneurysmal subarachnoid hemorrhage. This retrospectively study was to investigate the association of serum GPR with mortality in severe traumatic brain injury (sTBI).

Methods: Clinical data were retrospectively reviewed of isolated sTBI patients admitted within 12 h after trauma between January 2014 and January 2019. We analyzed relationships between admission serum GPR and post-traumatic 30-day mortality in addition to admission Glasgow coma scale (GCS) scores. Discriminative ability was evaluated using area under receiver operating characteristic curve (AUC).

Results: A total of 146 patients, of whom 37 (25.3%) died within 30 days following trauma, were included. Admission serum GPR emerged as an independent predictor for 30-day mortality (odds ratio, 5.256; 95% confidence interval (CI), 1.111-14.856) and overall survival (hazard ratio, 4.822; 95% CI, 1.157-12.870), with an AUC of 0.777 (95% CI, 0.693-0.835), which was equivalent to that of GCS scores (AUC, 0.831; 95% CI, 0.760-0.888; P = 0.179). There was a significant correlation between admission serum GPR and GCS scores (r² = 0.293).

Conclusions: Serum GPR in cases of sTBI is substantially associated with trauma severity and 30-day mortality. Therefore, the potential value of serum GPR for predicting short-term mortality of sTBI patients is favorable.