Work

Is admission lactate an independent prognostic marker or a reflection of injury severity in severe traumatic brain injury?

Year: 2026

Type: article

Abstract: Objective Although admission lactate is associated with poor outcomes after severe traumatic brain injury, its independent prognostic value remains uncertain. This study aimed to determine whether admission lactate is an independent prognostic marker or primarily a reflection of injury severity. Methods In a two-center retrospective study of patients with sTBI (GCS ≤ 8) (development cohort, n = 287; external validation cohort, n = 185), we assessed whether the association between admission lactate and 30-day mortality remained independent of established severity markers (age, GCS, pupillary reactivity, and Rotterdam CT score) and quantified the incremental prognostic value of lactate beyond this severity baseline, with external validation. Exploratory in vitro experiments in hypoxic SH-SY5Y cells were performed as a secondary analysis to examine cellular responses to lactate under hypoxic conditions. Results Thirty-day mortality was 42.2% in the development cohort and 36.8% in the external validation cohort. Admission lactate was significantly associated with mortality on univariable analysis (OR per mmol/L, 1.50; 95% CI, 1.30–1.73). After adjustment for severity markers, the adjusted OR was 1.19 per mmol/L (95% CI, 1.00–1.42; P = 0.051), indicating a positive association with limited precision. Consistent with this finding, lactate provided minimal incremental prognostic value beyond the severity baseline (ΔAUC, +0.005; P = 0.31), and these results were reproduced in the external validation cohort. Nevertheless, in vitro experiments suggested a potential biological activity of lactate that warrants further investigation. Conclusion In these two selected adult sTBI cohorts, admission lactate was associated with 30-day mortality but provided little incremental prognostic information beyond established neurological severity markers. Its role should therefore be interpreted as adjunctive rather than as a stand-alone prognostic factor. The exploratory in vitro findings warrant further mechanistic investigation.

Source: Frontiers in Neurology

DOI: 10.3389/fneur.2026.1920098