Trajectory of Functional Outcome up to 9 Years After Severe TBI: A TRACK-TBI Study

Research Objectives: To investigate changes in functional outcome among patients with severe TBI (sTBI) who completed a baseline assessment at 6 or 12 months and were followed up to 9 years post-injury.

Design: In this prospective observational study, participants were assessed by telephone on the Glasgow Outcome Scale- Extended (GOSE) at 6- or 12-months post-injury (ie, baseline) and then followed up to 3 more times between 2 and 9 years post-injury. For this analysis, we calculated cumulative mortality rates using the Kaplan-Meier estimator and calculated the proportion of surviving participants at 12 months who improved, declined, fluctuated, or remained stable on the GOSE by comparing the 12m baseline score to each of the 3 follow-up scores (n=94), and to the latest available follow-up score (n=146).

Setting: Level-1 Trauma Centers

Participants: TRACK-TBI is conducted at 18 level-1 trauma centers around the United States. A total of 302 eligible patients were included from the 3296 individuals in the TRACK-TBI U01 cohort. Participants were recruited from TRACK-TBI sites between February 2014 and August 2018, presenting upon Emergency Department (ED) arrival with a Glasgow Coma Scale (GCS) score of 3-8.

Interventions: Not applicable

Main Outcome Measures: Glasgow Outcome Measure (GOSE), mortality rates

Results: Among sTBI participants (77.8% male; mean [SD] age 40.4 [17.3] years; 79.1% white, 11.9% black, 8.9% other/unknown; mean [SD] total admission GCS score 4.3 [1.8]) who underwent baseline assessment, 48.3% completed at least one follow-up and 28.1% completed three follow-ups. Most deaths occurred during the first 12 months (27.6%), leveling off at 24 months (year 2: 30.0%; year 9: 35.2%). Comparing the baseline GOSE score the last available follow-up, the most common trajectory was “no change” (33%-56%, depending on time from injury to first follow-up) followed by “improved” (+1 point: 17%-25%; ≥2 points: 9%-23%) and “declined” (-1 point: 6%-17%; ≤-2 points: 3%-8%).

Conclusions: This study builds on prior TRACK-TBI and TBI Model System findings showing that the trajectory of recovery after sTBI remains dynamic across the first decade. In the majority of persons with sTBI who survive across the first year, functional outcome remains stable or improves between 1 and 9 years post-injury. Between 2 to 7 years post-sTBI, "no change" was found to be the least common trajectory observed. Among individuals showing functional changes after 2 years, improvement occurs more frequently than decline (35% versus 24%). These insights should be considered when establishing goals of care during acute hospitalization.

Author(s) Disclosures: No known COI