[Predictors of the recovery of cognitive functions in patients with traumatic brain injury]

After a traumatic brain injury (TBI), cognitive functionality may be severely altered. Some studies have aimed at identifying the best predictive variables for cognitive recovery, however, results still remain unclear.

To assess the recovery of cognitive functionality in TBI patients after a rehabilitation programme, and to identify the variables that best predict the cognitive recovery.

We conducted a retrospective pre-post study with 58 adult TBI patients that underwent an intensive rehabilitation programme. All of them were assessed using the cognitive functions sub-scale from the FIM+FAM scale, at admission and discharge. Both scores were compared using non-parametric test Wilcoxon. Cognitive functionality gain percentage was calculated and correlated with all the collected data. A multiple linear regression analysis was carried out to identify the best predictors of cognitive functionality gain percentage by introducing all clinical, demographic and cognitive information.

The group's cognitive functionality increased significantly from 33,6% to 85% (p < 0,01). Patients with higher cognitive functionality gain percentage were those with younger age, shorter time post-TBI, and higher scores on cognitive functions sub-scale, conditional attention and Luria's memory word tests. The best predictors for cognitive functionality gain percentage were time post-TBI and cognitive functions at admission (adjusted R(2) = 55,8%).

Patients who started rehabilitation sooner and had a higher cognitive functionality at admission, showed the greatest increase in cognitive functionality gain percentage. Other variables like age, or scores on cognitive tests must also be considered in future studies.