Osteoporosis Self-Assessment Tool for Asians Can Predict Neurologic Prognosis in Patients with Isolated Moderate Traumatic Brain Injury

Comorbidity in traumatic brain injury and functional outcomes: a systematic review

INTRODUCTION

Comorbidities in people with traumatic brain injury (TBI) may negatively impact injury recovery course and result in long-term disability. Despite the high prevalence of several categories of comorbidities in TBI, little is known about their association with patients' functional outcomes. We aimed to systematically review the current evidence to identify comorbidities that affect functional outcomes in adults with TBI.

EVIDENCE ACQUISITION

A systematic search of Medline, Cochrane Central Register of Controlled Trials, Embase and PsycINFO was conducted from 1997 to 2020 for prospective and retrospective longitudinal studies published in English. Three researchers independently screened and assessed articles for fulfillment of the inclusion criteria. Quality assessment followed the Quality in Prognosis Studies tool and the Scottish Intercollegiate Guidelines Network methodology recommendations.

EVIDENCE SYNTHESIS

Twenty-two studies of moderate quality discussed effects of comorbidities on functional outcomes of patients with TBI. Cognitive and physical functioning were negatively affected by comorbidities, although the strength of association, even within the same categories of comorbidity and functional outcome, differed from study to study. Severity of TBI, sex/gender, and age were important factors in the relationship. Due to methodological heterogeneity between studies, meta-analyses were not performed.

CONCLUSIONS

Emerging evidence highlights the adverse effect of comorbidities on functional outcome in patients with TBI, so clinical attention to this topic is timely. Future research on the topic should emphasize time of comorbidity onset in relation to the TBI event, to support prevention, treatment, and rehabilitation. PROSPERO registration (CRD 42017070033).

Bone Marrow Derived Extracellular Vesicles Activate Osteoclast Differentiation in Traumatic Brain Injury Induced Bone Loss

Traumatic brain injury (TBI) is a major source of worldwide morbidity and mortality. Patients suffering from TBI exhibit a higher susceptibility to bone loss and an increased rate of bone fractures; however, the underlying mechanisms remain poorly defined. Herein, we observed significantly lower bone quality and elevated levels of inflammation in bone and bone marrow niche after controlled cortical impact-induced TBI in in vivo CD-1 mice. Further, we identified dysregulated NF-κB signaling, an established mediator of osteoclast differentiation and bone loss, within the bone marrow niche of TBI mice. Ex vivo studies revealed increased osteoclast differentiation in bone marrow-derived cells from TBI mice, as compared to sham injured mice. We also found bone marrow derived extracellular vesicles (EVs) from TBI mice enhanced the colony forming ability and osteoclast differentiation efficacy and activated NF-κB signaling genes in bone marrow-derived cells. Additionally, we showed that miRNA-1224 up-regulated in bone marrow-derived EVs cargo of TBI. Taken together, we provide evidence that TBI-induced inflammatory stress on bone and the bone marrow niche may activate NF-κB leading to accelerated bone loss. Targeted inhibition of these signaling pathways may reverse TBI-induced bone loss and reduce fracture rates.

Association between the Osteoporosis Self-Assessment Tool for Asians Score and Mortality in Patients with Isolated Moderate and Severe Traumatic Brain Injury: A Propensity Score-Matched Analysis

Background: The purpose of this study was to use a propensity score-matched analysis to investigate the association between the Osteoporosis Self-Assessment Tool for Asians (OSTA) scores and clinical outcomes of patients with isolated moderate and severe traumatic brain injury (TBI). Methods: The study population comprised 7855 patients aged ≥40 years who were hospitalized for treatment of isolated moderate and severe TBI (an Abbreviated Injury Scale (AIS) ≥3 points only in the head and not in other regions of the body) between 1 January 2009 and 31 December 2014. Patients were categorized as high-risk (OSTA score < -4; n = 849), medium-risk (-4 ≤ OSTA score ≤ -1; n = 1647), or low-risk (OSTA score > -1; n = 5359). Two-sided Pearson's chi-squared, or Fisher's exact tests were used to compare categorical data. Unpaired Student's t-test and Mann-Whitney U test were performed to analyze normally and non-normally distributed continuous data, respectively. Propensity score-matching in a 1:1 ratio was performed using NCSS software, with adjustment for covariates. Results: Compared to low-risk patients, high- and medium-risk patients were significantly older and injured more severely. The high- and medium-risk patients had significantly higher mortality rates, longer hospital length of stay, and a higher proportion of admission to the intensive care unit than low-risk patients. Analysis of propensity score-matched patients with adjusted covariates, including gender, co-morbidity, blood alcohol concentration level, Glasgow Coma Scale score, and Injury Severity Score revealed that high- and medium-risk patients still had a 2.4-fold (odds ratio (OR), 2.4; 95% confidence interval (CI), 1.39-4.15; p = 0.001) and 1.8-fold (OR, 1.8; 95% CI, 1.19-2.86; p = 0.005) higher mortality, respectively, than low-risk patients. However, further addition of age as a covariate for the propensity score-matching demonstrated that there was no significant difference between high-risk and low-risk patients or between medium-risk and low-risk patients, implying that older age may contribute to the significantly higher mortality associated with a lower OSTA score. Conclusions: Older age may be able to explain the association of lower OSTA score and higher mortality rates in patients with isolated moderate and severe TBI.