Effects of Red Blood Cell Transfusion on Long-Term Disability of Patients with Traumatic Brain Injury

Background This 3-year prospective study examined the association between red blood cell transfusion (RBCT) and 1-year neurocognitive and disability levels in 309 patients with traumatic brain injury (TBI) admitted to the neurological intensive care unit (NICU). Methods Using a telephone interview-based survey, functional outcomes were assessed by the Glasgow Outcome Scale (GOS), Rancho Los Amigos Levels of Cognitive Functioning Scale (RLCFS), and Disability Rating Scale (DRS) and dichotomized as favorable and unfavorable (dependent variable). The adjusted influence of RBCT on unfavorable results was assessed by conventional logistic regression, controlling for illness severity and propensity score (introduced as a continuous variable and by propensity score-matched patients). Results Overall, 164 (53 %) patients received ≥1 unit of RBCT during their NICU stay. One year postinjury, transfused patients exhibited significantly higher unfavorable GOS (46.0 vs. 22.0 %), RLCFS (37.4 vs. 15.4 %), and DRS (39.6 vs. 18.7 %) scores than nontransfused patients. Although transfused patients were more severely ill upon admission, their adjusted odds ratios (95 % confidence intervals) for unfavorable GOS, RLCFS, and DRS scores were 2.5 (1.2–5.1), 3.0 (1.4–6.3), and 2.3 (1.1–4.8), respectively. These odds ratios remained largely unmodified when the calculated propensity score was incorporated as an independent continuous variable into the multivariate analysis. Furthermore, in 76 pairs of propensity score-matched patients, the rate of an unfavorable RLCFS score at the 1-year (but not 6-month) follow-up was significantly higher in transfused than nontransfused patients [3.0 (1.1–8.2)]. Conclusion Our results strongly suggest an independent association between RBCT and unfavorable long-term functional outcomes of patients with TBI.