β-Blocker after severe traumatic brain injury is associated with better long-term functional outcome: a matched case control study

Purpose Severe traumatic brain injury (TBI) is the predominant cause of death and disability following trauma. Several studies have observed improved survival in TBI patients exposed to beta-blockers, however, the effect on functional outcome is poorly documented. Methods Adult patients with severe TBI (head AIS >= 3) were identified from a prospectively collected TBI database over a 5-year period. Patients with neurosurgical ICU length of stay < 48 h and those dying within 48 h of admission were excluded. Patients exposed to beta-blockers <= 48 h after admission and who continued with treatment until discharge constituted beta-blocked cases and were matched to non beta-blocked controls using propensity score matching. The outcome of interest was Glasgow Outcome Scores (GOS), as a measure of functional outcome up to 12 months after injury. GOS <= 3 was considered a poor outcome. Bivariate analysis was deployed to determine differences between groups. Odds ratio and 95% CI were used to assess the effect of beta-blockers on GOS. Results 362 patients met the inclusion criteria with 21% receiving beta-blockers during admission. After propensity matching, 76 matched pairs were available for analysis. There were no statistical differences in any variables included in the analysis. Mean hospital length of stay was shorter in the beta-blocked cases (18.0 vs. 26.8 days, p < 0.01). The risk of poor long-term functional outcome was more than doubled in non-beta-blocked controls (OR 2.44, 95% CI 1.01-6.03, p = 0.03). Conclusion Exposure to beta-blockers in patients with severe TBI appears to improve functional outcome. Further prospective randomized trials are warranted.