# Factors Affecting Recovery from Post-Traumatic Amnesia During Inpatient Brain Injury Rehabilitation: A Retrospective Cohort Study

## TL;DR

This study found that older age and longer hospital stays are linked to longer post-traumatic amnesia in brain injury patients.

## Contribution

The study identifies specific clinical and demographic factors that predict prolonged post-traumatic amnesia in traumatic brain injury patients.

## Key findings

- Older age and longer acute hospital stays significantly increase the risk of prolonged post-traumatic amnesia.
- Higher admission Functional Independence Measure scores are associated with shorter post-traumatic amnesia duration.
- ICU admission and longer ICU stays correlate with prolonged post-traumatic amnesia.

## Abstract

Background: Longer post-traumatic amnesia (PTA) durations in traumatic brain injury (TBI) are associated with worse functional outcomes, poorer cognition, and persistent disability. A retrospective cohort study was conducted to evaluate factors affecting PTA duration and emergence. Methods: Data extraction of discharged records of adult TBI was performed between 1 April 2022 and 4 May 2023. Independent variables collected include socio-demographic, acute TBI, and rehabilitation characteristics. Admission/discharge Functional Independence Measure (FIM) was the main rehabilitation outcome measure charted. Dependent variables included PTA duration ≤ 30 days, >30 days, and PTA emergence. Results: A total of 189 datasets were analysed. Median age (IQR) 64 years (26), 145 males (76.7%), and 64.6% >55 years. PTA ≥ 30 days were correlated with the following factors: older age (66 years vs. 59.5 years, p = 0.017), presence of ICU admission (75.2% vs. 61.4%, p = 0.029), longer ICU stays (5 days vs. 3 days, p = 0.001), and longer duration of inpatient hospitalization (acute length of stay, ALOS 23 days vs. ALOS 14 days, p < 0.001). Age ≥ 55 years were 5.6 times as likely (p = 0.011) to be in prolonged PTA, an additional day’s stay in the acute hospital increased the odds by 1.15 (p < 0.001), and every score lost in the total admission FIM from 40 and below increased the odds of prolonged PTA by 3.35 times (p = 0.014). Conclusions: This study demonstrated that older age at TBI onset and longer ALOS significantly increased the risk of prolonged PTA duration. Conversely, higher admission FIM score, lower age at admission, and shorter ALOS were associated with lower PTA duration.