Neurologic disorders, in-hospital deaths, and years of potential life lost in the USA, 1988-2011

Cross-sectional study of major procedure codes among hospitalized patients with traumatic brain injury by level of injury severity in the 2004 to 2014 Nationwide Inpatient Sample

Despite its public health significance, TBI management across US healthcare institutions and patient characteristics with an emphasis on utilization and outcomes of TBI-specific procedures have not been evaluated at the national level.We aimed to characterize top 10 procedure codes among hospitalized adults with TBI as primary diagnosis by injury severity.A Cross-sectional study was conducted using 546, 548 hospitalization records from the 2004 to 2014 Nationwide Inpatient Sample were analyzed.Data elements of interest included injury, patient, hospital characteristics, procedures, in-hospital death and length of stay.Ten top procedure codes were "Closure of skin and subcutaneous tissue of other sites", "Insertion of endotracheal tube", "Continuous invasive mechanical ventilation for less than 96 consecutive hours", "Venous catheterization (not elsewhere classified)", "Continuous invasive mechanical ventilation for 96 consecutive hours or more", "Transfusion of packed cells", "Incision of cerebral meninges", "Serum transfusion (not elsewhere classified)", "Temporary tracheostomy", and "Arterial catherization". Prevalence rates ranged between 3.1% and 15.5%, with variations according to injury severity and over time. Whereas "Closure of skin and subcutaneous tissue of other sites" was associated with fewer in-hospital deaths and shorter hospitalizations, "Temporary tracheostomy" was associated with fewer in-hospital deaths among moderate-to-severe TBI patients, and "Continuous invasive mechanical ventilation for less than 96 consecutive hours" was associated with shorter hospitalizations among severe TBI patients. Other procedures were associated with worse outcomes.Nationwide, the most frequently reported hospitalization procedure codes among TBI patients aimed at homeostatic stabilization and differed in prevalence, trends, and outcomes according to injury severity.

Genetic Variability and Trajectories of DNA Methylation May Support a Role for HAMP in Patient Outcomes After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND/OBJECTIVE

Preclinical evidence suggests that iron homeostasis is an important biological mechanism following aneurysmal subarachnoid hemorrhage (aSAH); however, this concept is underexplored in humans. This study examined the relationship between patient outcomes following aSAH and genetic variants and DNA methylation in the hepcidin gene (HAMP), a key regulator of iron homeostasis.

METHODS

In this exploratory, longitudinal observational study, participants with verified aSAH were monitored for acute outcomes including cerebral vasospasm (CV) and delayed cerebral ischemia (DCI) and evaluated post-discharge at 3 and 12 months for long-term outcomes of death and functional status using the Modified Rankin Scale (mRS; poor = 3-6) and Glasgow Outcome Scale (GOS; poor = 1-3). Participants were genotyped for two genetic variants, and DNA methylation data were collected from serial cerebrospinal fluid over 14 days post-aSAH at eight methylation sites within HAMP. Participants were grouped based on their site-specific DNA methylation trajectory, with and without correcting for cell-type heterogeneity (CTH), and the associations between genetic variants and inferred DNA methylation trajectory groups and patient outcomes were tested. To correct for multiple testing, an empirical significance threshold was computed using permutation testing.

RESULTS

Genotype data for rs10421768 and rs7251432 were available for 241 and 371 participants, respectively, and serial DNA methylation data were available for 260 participants. Acute outcome prevalence included CV in 45% and DCI in 37.1% of the overall sample. Long-term outcome prevalence at 3 and 12 months included poor GOS in 23% and 21%, poor mRS in 31.6% and 27.3%, and mortality in 15.1% and 18.2%, respectively, in the overall sample. Being homozygous for the rs7251432 variant allele was significantly associated with death at 3 months (p = 0.003) and was the only association identified that passed adjustment for multiple testing mentioned above. Suggestive associations (defined as trending toward significance, p value < 0.05, but not meeting empirical significance thresholds) were identified between the homozygous variant allele for rs7251432 and poor GOS and mRS at 3 months (both p = 0.04) and death at 12 months (p = 0.02). For methylation trajectory groups, no associations remained significant after correction for multiple testing. However, for methylation trajectory groups not adjusted for CTH, suggestive associations were identified between cg18149657 and poor GOS and mRS at 3 months (p = 0.003 and p = 0.04, respectively) and death at 3 months (p = 0.04), and between cg26283059 and DCI (p = 0.01). For methylation trajectory groups adjusted for CTH, suggestive associations were identified between cg02131995 and good mRS at 12 months (p = 0.02), and between cg26283059 and DCI (p = 0.01).

CONCLUSIONS

This exploratory pilot study offers preliminary evidence that HAMP may play a role in patient outcomes after aSAH. Replication of this study and mechanistic investigation of the role of HAMP in patient outcomes after aSAH are needed.

Systematic review of trauma system regionalization and implementation on outcomes in traumatic brain injury patients

BACKGROUND

The number of trauma systems has increased dramatically within the United States over the past 40 years. The implementation of these systems has contributed to a decrease in mortality and improved outcomes in patients with trauma. Several studies have evaluated the effect of implementation of these systems on outcomes, but few studies examine the effects of such systems specifically on traumatic brain injury (TBI).

METHODS

A systematic review of the literature was conducted according the guidelines for the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to determine the effects of trauma system implementation and regionalization on mortality and other outcome measures in adult TBI. We sought to include both experimental and observational studies within the United States.

RESULTS

From 1983 to 2015, nine studies were identified that adhered to the predefined inclusion and exclusion criteria representing six different geographic areas within the United States. All studies utilized a retrospective pre-post implementation methodology. A variety of mortality outcome measures were identified in the literature. Six of the nine studies demonstrated some benefit on various mortality metrics.

CONCLUSION

The existing literature on the effects of trauma system implementation or regionalization on outcomes in TBI is sparse but overall seems to convey an improvement in mortality.

Years of Potential Life Lost Because of Cardiovascular Disease in Asian-American Subgroups, 2003-2012

Background

Asian‐American subgroups (Asian‐Indian, Chinese, Filipino, Korean, Japanese, and Vietnamese) display varied cardiovascular disease mortality patterns, especially at younger ages. This study aims to examine the years of potential life lost because of ischemic heart disease and cerebrovascular disease among the 6 largest Asian‐American subgroups compared with non‐Hispanic whites.

Methods and Results

We used National Center for Health Statistics Multiple Causes of Death mortality files from 2003 to 2012 to calculate race‐specific life expectancy, mean years of potential life lost, and years of potential life lost per 100 000 population for each Asian subgroup and non‐Hispanic whites. Asian‐American subgroups display heterogeneity in cardiovascular disease burden. Asian‐Indians had a high burden of ischemic heart disease; Asian‐Indian men lost 724 years per 100 000 population in 2012 and a mean of 17 years to ischemic heart disease. Respectively, Vietnamese and Filipino men and women lost a mean of 17 and 16 years of life to cerebrovascular disease; Filipino men lost 352 years per 100 000 population in 2012. All Asian subgroups for both sexes had higher years of life lost to cerebrovascular disease compared with non‐Hispanic whites.

Conclusions

Cardiovascular disease burden varies among Asian subgroups, and contributes to greater premature mortality in certain subgroups. Asian‐Indian and Filipino populations have the highest years of life lost because of ischemic heart disease and Filipino and Vietnamese have the highest years of life lost because of cerebrovascular disease. Analysis of risk factors and development of subgroup‐specific interventions are required to address these health disparities.

Two latent classes of diagnostic and treatment procedures among traumatic brain injury inpatients

To characterize latent classes of diagnostic and/or treatment procedures among hospitalized U.S. adults, 18-64 years, with primary diagnosis of TBI from 2004-2014 Nationwide Inpatient Samples, latent class analysis (LCA) was applied to 10 procedure groups and differences between latent classes on injury, patient, hospital and healthcare utilization outcome characteristics were modeled using multivariable regression. Using 266,586 eligible records, LCA resulted in two classes of hospitalizations, namely, class I (n = 217,988) (mostly non-surgical) and class II (n = 48,598) (mostly surgical). Whereas orthopedic procedures were equally likely among latent classes, skin-related, physical medicine and rehabilitation procedures as well as behavioral health procedures were more likely among class I, and other types of procedures were more likely among class II. Class II patients were more likely to have moderate-to-severe TBI, to be admitted on weekends, to urban, medium-to-large hospitals in Midwestern, Southern or Western regions, and less likely to be > 30 years, female or non-White. Class II patients were also less likely to be discharged home and necessitated longer hospital stays and greater hospitalization charges. Surgery appears to distinguish two classes of hospitalized patients with TBI with divergent healthcare needs, informing the planning of healthcare services in this target population.

Defining New Research Questions and Protocols in the Field of Traumatic Brain Injury through Public Engagement: Preliminary Results and Review of the Literature

Traumatic brain injury (TBI) is the most common cause of death and disability in the age group below 40 years. The financial cost of loss of earnings and medical care presents a massive burden to family, society, social care, and healthcare, the cost of which is estimated at £1 billion per annum (about brain injury (online)). At present, we still lack a full understanding on the pathophysiology of TBI, and biomarkers represent the next frontier of breakthrough discoveries. Unfortunately, many tenets limit their widespread adoption. Brain tissue sampling is the mainstay of diagnosis in neuro-oncology; following on this path, we hypothesise that information gleaned from neural tissue samples obtained in TBI patients upon hospital admission may correlate with outcome data in TBI patients, enabling an early, accurate, and more comprehensive pathological classification, with the intent of guiding treatment and future research. We proposed various methods of tissue sampling at opportunistic times: two methods rely on a dedicated sample being taken; the remainder relies on tissue that would otherwise be discarded. To gauge acceptance of this, and as per the guidelines set out by the National Research Ethics Service, we conducted a survey of TBI and non-TBI patients admitted to our Trauma ward and their families. 100 responses were collected between December 2017 and July 2018, incorporating two redesigns in response to patient feedback. 75.0% of respondents said that they would consent to a brain biopsy performed at the time of insertion of an intracranial pressure (ICP) bolt. 7.0% replied negatively and 18.0% did not know. 70.0% would consent to insertion of a jugular bulb catheter to obtain paired intracranial venous samples and peripheral samples for analysis of biomarkers. Over 94.0% would consent to neural tissue from ICP probes, external ventricular drains (EVD), and lumbar drains (LD) to be salvaged, and 95.0% would consent to intraoperative samples for further analysis.

Analysis of incidence of traumatic brain injury in blunt trauma patients with Glasgow Coma Scale of 12 or less

PURPOSE

Early diagnosis of traumatic brain injury (TBI) is important for improving survival and neurologic outcome in trauma victims. The purpose of this study was to assess whether Glasgow Coma Scale (GCS) of 12 or less can predict the presence of TBI and the severity of associated injuries in blunt trauma patients.

METHODS

A retrospective cohort study including 303,435 blunt trauma patients who were transferred from the scene to hospital from 1998 to 2013. The data was obtained from the records of the National Trauma Registry maintained by Israel's National Center for Trauma and Emergency Medicine Research, in the Gertner Institute for Epidemiology and Health Policy Research. All blunt trauma patients with GCS 12 or less were included in this study. Data collected in the registry include age, gender, mechanism of injury, GCS, initial blood pressure, presence of TBI and incidence of associated injuries. Patients younger than 14 years old and trauma victims with GCS 13-15 were excluded from the study. Statistical analysis was performed by using Statistical Analysis Software Version 9.2. Statistical tests performed included Chi-square tests. A p-value less than 0.05 was considered statistically significant.

RESULTS

There were 303,435 blunt trauma patients, 8731 (2.9%) of them with GCS of 3-12 that including 6351 (72%) patients with GCS of 3-8 and 2380 (28%) patient with GCS of 9-12. In these 8731 patients with GCS of 3-12, 5372 (61.5%) patients had TBI. There were total 1404 unstable patients in all the blunt trauma patients with GCS of 3-12, 1256 (89%) patients with GCS 3-8, 148 (11%) patients with GCS 9-12. In the 5095 stable blunt trauma patients with GCS 3-8, 32.4% of them had no TBI. The rate in the 2232 stable blunt trauma patients with GCS 9-12 was 50.1%. In the unstable patients with GCS 3-8, 60.5% of them had TBI, and in subgroup of patients with GCS 9-12, only 37.2% suffered from TBI.

CONCLUSION

The utility of a GCS 12 and less is limited in prediction of brain injury in multiple trauma patients. Significant proportion of trauma victims with low GCS had no TBI and their impaired neurological status is related to severe extra-cranial injuries. The findings of this study showed that using of GCS in initial triage and decision making processes in blunt trauma patients needs to be re-evaluated.

Hospital Mortality Among Elderly Patients Admitted With Neurological Disorders Was Not Predicted by any Particular Diagnosis in a Tertiary Medical Center

Background:

Neurological disorders (NDs) are associated with high hospital mortality. We aimed to identify predictors of hospital mortality among elderly inpatients with NDs.

Methods:

Patients aged ≥60 years admitted to the hospital between January 1, 2009 and December 31, 2010 with acute NDs, chronic NDs as underpinnings of acute clinical disorders, and neurological complications of other diseases were studied. We analyzed demographic data, NDs, and comorbidities as independent predictors of hospital mortality. Logistic regression was performed for multivariable analysis.

Results:

Overall, 1540 NDs and 2679 comorbidities were identified among 798 inpatients aged ≥ 60 years (mean 75.8±9.1). Of these, 54.5% were female. Diagnostic frequency of NDs ranged between 0.3% and 50.8%. Diagnostic frequency of comorbidities ranged from 5.6% to 84.5%. Comorbidities varied from 0 to 9 per patient (90% of patients had ≥2 comorbidities), mean 3.2±1.47(CI, 3.1-3.3). Patients with multimorbidities presented with a mean of 4.7±1.7 morbidities per patient. Each ND and comorbidity were associated with high hospital mortality, producing narrow ranges between the lowest and highest incidences of death (hospital mortality = 18%) (95% CI, 15%-21%). After multivariable analysis, advanced age (P<0.001) and low socioeconomic status (P=0.003) were recognized as predictors of mortality, totaling 9% of the variables associated with hospital mortality.

Conclusion:

Neither a particular ND nor an individual comorbidity predicted hospital mortality. Age and low socioeconomic class accounted for 9% of predictors. We suggest evaluating whether functional, cognitive, or comorbidity scores will improve the risk model of hospital mortality in elderly patients admitted with ND.

Feasibility of stereotactic catheter ventriculocisternostomy for cisternal lavage therapy in patients with subarachnoid hemorrhage

OBJECTIVE

Delayed cerebral infarction (DCI) confers considerable morbidity and mortality after aneurysmal subarachnoid hemorrhage (aSAH). Available prevention strategies are insufficient. Cisternal blood clearance by stereotactic catheter ventriculocisternostomy (STX-VCS) and cisternal lavage therapy is a novel concept for DCI prevention. Here, we assess the general feasibility, pitfalls and imaging requirements of STX-VCS after aSAH.

PATIENTS AND METHODS

73 aSAH patients admitted between 2008 and 2015 with appropriate imaging for simulation of stereotactic procedures were included. Surgical feasibility of a transventricular trajectory to the basal cisterns was assessed.

RESULTS

Transventricular catheter access to the basal cisterns was feasible in 94% of cases. In 6% vascular obstacles precluded a transventricular approach and access to the basal cisterns could be simulated via a transparenchymal trajectory. CT-artifacts that interfered with stereotactic planning were observed in 58% after coiling and 5% after clipping. In these cases stereotactic planning was enabled by MRI. Logistic regression of aneurysm size and distance-to-target allowed for precise prediction whether MRI was required for stereotactic planning of STX-VCS after coiling.

CONCLUSIONS

Stereotactic catheter access to the basal cisterns after aSAH appears to be generally feasible. Coil artifacts compromising CT-based planning can be precisely anticipated and planning enabled by MRI.

Frequency, associated features, and burden of neurological disorders in older adult inpatients in Brazil: a retrospective cross-sectional study

Background

The burden of neurological disorders (NDs) in older adult inpatients is often underestimated. We studied diagnostic frequency and comorbidity of NDs among inpatients aged ≥60 years. We compared rates of hospital mortality, length of stay (LOS), and readmission with younger patient counterparts (aged 18–59 years) and older adult non-neurological patients.

Methods

This was a retrospective cross-sectional study of inpatients in a tertiary care center in Brazil. We compiled data for all patients admitted between 1 January 2009 and 31 December 2010, and selected those aged ≥18 years for inclusion in the study. We collected data for inpatients under care of a clinical neurologist who were discharged with primary diagnoses of NDs or underlying acute clinical disorders, and data for complications in clinical or surgical inpatients. Patients who remained hospitalized for more than 9 days were categorized as having long LOS.

Results

Older adult inpatients with NDs (n = 798) represented 56% of all neurological inpatients aged ≥18 years (n = 1430), and 14% of all geriatric inpatients (n = 5587). The mean age of older adult inpatients was 75 ± 9.1 years. Women represented 55% of participants. The most common NDs were cerebrovascular diseases (51%), although multimorbidity was observed. Hospital mortality rate was 18% (95% confidence interval [CI], 15–21) and readmission rate was 31% (95% CI, 28–35), with 40% of patients readmitted 1.8 ± 1.5 times. The long LOS rate was 51% and the median LOS was 9 days (interquartile interval, 1–20 days). In younger inpatients mortality rate was 1.4%, readmission rate was 34%, and long LOS rate was 14%. In older adult non-neurological inpatients, mortality rate was 22%, readmission rate was 49%, and long LOS rate was 30%.

Conclusions

Older adult neurological inpatients had the highest long LOS rate of all patient groups, and a higher mortality rate than neurological patients aged 18–59 years. Readmissions were high in all groups studied, particularly among older adult non-neurological inpatients. Improved structures and concerted efforts are required in hospitals in Brazil to reduce burden of NDs in older adult patients.

Response of the cerebral vasculature following traumatic brain injury

The critical role of the vasculature and its repair in neurological disease states is beginning to emerge particularly for stroke, dementia, epilepsy, Parkinson's disease, tumors and others. However, little attention has been focused on how the cerebral vasculature responds following traumatic brain injury (TBI). TBI often results in significant injury to the vasculature in the brain with subsequent cerebral hypoperfusion, ischemia, hypoxia, hemorrhage, blood-brain barrier disruption and edema. The sequalae that follow TBI result in neurological dysfunction across a host of physiological and psychological domains. Given the importance of restoring vascular function after injury, emerging research has focused on understanding the vascular response after TBI and the key cellular and molecular components of vascular repair. A more complete understanding of vascular repair mechanisms are needed and could lead to development of new vasculogenic therapies, not only for TBI but potentially vascular-related brain injuries. In this review, we delineate the vascular effects of TBI, its temporal response to injury and putative biomarkers for arterial and venous repair in TBI. We highlight several molecular pathways that may play a significant role in vascular repair after brain injury.

Integrating Palliative Care Into the Care of Neurocritically Ill Patients: A Report From the Improving Palliative Care in the ICU Project Advisory Board and the Center to Advance Palliative Care

OBJECTIVES

To describe unique features of neurocritical illness that are relevant to provision of high-quality palliative care; to discuss key prognostic aids and their limitations for neurocritical illnesses; to review challenges and strategies for establishing realistic goals of care for patients in the neuro-ICU; and to describe elements of best practice concerning symptom management, limitation of life support, and organ donation for the neurocritically ill.

DATA SOURCES

A search of PubMed and MEDLINE was conducted from inception through January 2015 for all English-language articles using the term "palliative care," "supportive care," "end-of-life care," "withdrawal of life-sustaining therapy," "limitation of life support," "prognosis," or "goals of care" together with "neurocritical care," "neurointensive care," "neurological," "stroke," "subarachnoid hemorrhage," "intracerebral hemorrhage," or "brain injury."

DATA EXTRACTION AND SYNTHESIS

We reviewed the existing literature on delivery of palliative care in the neurointensive care unit setting, focusing on challenges and strategies for establishing realistic and appropriate goals of care, symptom management, organ donation, and other considerations related to use and limitation of life-sustaining therapies for neurocritically ill patients. Based on review of these articles and the experiences of our interdisciplinary/interprofessional expert advisory board, this report was prepared to guide critical care staff, palliative care specialists, and others who practice in this setting.

CONCLUSIONS

Most neurocritically ill patients and their families face the sudden onset of devastating cognitive and functional changes that challenge clinicians to provide patient-centered palliative care within a complex and often uncertain prognostic environment. Application of palliative care principles concerning symptom relief, goal setting, and family emotional support will provide clinicians a framework to address decision making at a time of crisis that enhances patient/family autonomy and clinician professionalism.

A Nationwide Analysis of Outcomes of Weekend Admissions for Intracerebral Hemorrhage Shows Disparities Based on Hospital Teaching Status

BACKGROUND AND PURPOSE

With the "weekend effect" being well described, the Brain Attack Coalition released a set of "best practice" guidelines in 2005, with the goal to uniformly provide standard of care to patients with stroke. We attempted to define a "weekend effect" in outcomes among patients with intracranial hemorrhage (ICH) over the last decade, utilizing the Nationwide Inpatient Sample (NIS) data. We also attempted to analyze the trend of such an effect.

MATERIALS AND METHODS

We determined the association of ICH weekend admissions with hospital outcomes including mortality, adverse discharge, length of stay, and cost compared to weekday admissions using multivariable logistic regression. We extracted our study cohort from the NIS, the largest all-payer data set in the United States.

RESULTS

Of 485 329 ICH admissions from 2002 to 2011, 27.5% were weekend admissions. Overall, weekend admissions were associated with 11% higher odds of in-hospital mortality. When analyzed in 3-year groups, excess mortality of weekend admissions showed temporal decline. There was higher mortality with weekend admissions in nonteaching hospitals persisted (odds ratios 1.16, 1.13, and 1.09, respectively, for 3-year subgroups). Patients admitted during weekends were also 9% more likely to have an adverse discharge (odds ratio 1.09; 95% confidence interval: 1.07-1.11; P < .001) with no variation by hospital status. There was no effect of a weekend admission on either length of stay or cost of care.

CONCLUSION

Nontraumatic ICH admissions on weekends have higher in-hospital mortality and adverse discharge. This demonstrates need for in-depth review for elucidating this discrepancy and stricter adherence to standard-of-care guidelines to ensure uniform care.

Elevated relative risk of aneurysmal subarachnoid hemorrhage with colder weather in the mid-Atlantic region

We have previously reported an increase of 0.6% in the relative risk of aneurysmal subarachnoid hemorrhage (aSAH) in response to every 1°F decrease in the maximum daily temperature (Tmax) in colder seasons from patients presenting to our regional tertiary care center. We hypothesized that this relationship would also be observed in the warmer summer months with ambient temperatures greater than 70°F. From prospectively collected incidence data for aSAH patients, we investigated absolute Tmax, average daily temperatures, intraday temperature ranges, and the variation of daily Tmax relative to 70°F to assess associations with aSAH incidence for patients admitted to our institution between 1991 and 2009 during the hottest months and days on which Tmax>70°F. For all days treated as a group, the mean Tmax (± standard deviation) was lower when aSAH occurred than when it did not (64.4±18.2°F versus 65.8±18.3°F; p=0.016). During summer months, the odds ratio (OR) of aSAH incidence increased with lower mean Tmax (OR 1.019; 95% confidence interval 1.001-1.037; p=0.043). The proportion of days with aSAH admissions was lower on hotter days than the proportion of days with no aSAH (96% versus 98%; p=0.006). aSAH were more likely to occur during the summer and on days with a temperature fluctuation less than 10°F (8% versus 4%; p=0.002). During the hottest months of the year in the mid-Atlantic region, colder maximum daily temperatures, a smaller heat burden above 70°F, and smaller intraday temperature fluctuations are associated with increased aSAH admissions in a similar manner to colder months. These findings support the hypothesis that aSAH incidence is more likely with drops in temperature, even in the warmer months.

Role of Microvascular Disruption in Brain Damage from Traumatic Brain Injury

Traumatic brain injury (TBI) is acquired from an external force, which can inflict devastating effects to the brain vasculature and neighboring neuronal cells. Disruption of vasculature is a primary effect that can lead to a host of secondary injury cascades. The primary effects of TBI are rapidly occurring while secondary effects can be activated at later time points and may be more amenable to targeting. Primary effects of TBI include diffuse axonal shearing, changes in blood-brain barrier (BBB) permeability, and brain contusions. These mechanical events, especially changes to the BBB, can induce calcium perturbations within brain cells producing secondary effects, which include cellular stress, inflammation, and apoptosis. These secondary effects can be potentially targeted to preserve the tissue surviving the initial impact of TBI. In the past, TBI research had focused on neurons without any regard for glial cells and the cerebrovasculature. Now a greater emphasis is being placed on the vasculature and the neurovascular unit following TBI. A paradigm shift in the importance of the vascular response to injury has opened new avenues of drug-treatment strategies for TBI. However, a connection between the vascular response to TBI and the development of chronic disease has yet to be elucidated. Long-term cognitive deficits are common amongst those sustaining severe or multiple mild TBIs. Understanding the mechanisms of cellular responses following TBI is important to prevent the development of neuropsychiatric symptoms. With appropriate intervention following TBI, the vascular network can perhaps be maintained and the cellular repair process possibly improved to aid in the recovery of cellular homeostasis.