Serum periostin concentrations and outcomes after severe traumatic brain injury.

•Serum periostin levels are significantly elevated after severe traumatic brain injury.•Serum periostin levels are related to trauma severity determined by Glasgow Coma Scale scores.•Periostin in serum is an independent predictor for 30-day mortality and overall survival.•Serum periostin levels show similar prognostic value compared with Glasgow Coma Scale scores.