Long-term risk of cardiovascular disease after traumatic brain injury: screening and prevention

Traumatic brain injury persistently increases the incidence of both ischemic and hemorrhagic strokes: Potential mechanisms

Traumatic brain injuries (TBI) significantly increase the risk of both ischemic and hemorrhagic strokes, with effects persisting for years after the initial injury. The mechanisms underlying this increased stroke risk are complex, multifactorial, and incompletely understood but likely include chronic cerebrovascular dysfunction, blood-brain barrier disruption, and inflammatory responses. Epidemiological studies consistently show that TBI is an independent risk factor for stroke, with more severe injuries associated with greater risk, especially for hemorrhagic strokes. Traditional risk factors for stroke, such as hypertension, poor diet, and sedentary lifestyle, further elevate the risk in TBI survivors. Modifiable lifestyle factors, such as improving sleep, increasing physical activity, and adopting heart-healthy diets, offer potential intervention points to mitigate stroke risk. Pharmacological considerations, including the use of antidepressants, anticoagulants, and statins, also influence stroke risk, particularly with regard to hemorrhagic complications. This review explores the pathophysiological mechanisms linking TBI and stroke, emphasizing the need for future research to identify specific biomarkers and imaging techniques to predict stroke vulnerability in TBI patients. Addressing the gaps in understanding, particularly regarding small vessel pathology, will be essential to developing targeted therapies for reducing stroke incidence in TBI survivors.

Danshen-Chuanxiong-Honghua ameliorates neurological function and inflammation in traumatic brain injury in rats via modulating Ghrelin/GHSR

ETHNOPHARMACOLOGICAL RELEVANCE

Guanxin II, proposed by Chen Keji (National master of traditional Chinese medicine), possesses neuroprotective effect. Interestingly, its simplified prescription Danshen-Chuanxiong-Honghua (DCH) can also clinically ameliorate cerebral impairment and improve spatial cognitive deficits, similar to the function of original formula.

AIM OF THE STUDY

We aimed to elucidate the rationality of DCH's natural existence, qualitatively identify DCH-derived phytochemicals, thereby to validate cerebral protective effect, and expose the potential mechanism of DCH and its main absorbed compound ferulic acid (FA).

MATERIALS AND METHODS

The natural rationality of DCH's existence for treating TBI was verified using data mining. The qualitative analysis of DCH extract-derived phytochemicals was conducted through liquid chromatography with mass spectrometry (LC-MS). Controlled cortical impact (CCI) was chosen to establish TBI model. Neurological behavior tests, blood-brain barrier (BBB) permeability test, brain water content measurement, and proinflammatory factors consisting of IL-6, IL-1β, and TNF-α of plasma, and HPA axis-related hormone levels of DA, NA, 5-HT, ghrelin, and BDNF in hippocampus were analyzed by enzyme-linked immunosorbent assay. Network pharmacology was employed to predict potential targets and pathways of DCH intervening TBI. Growth hormone secretagogue receptor (GHSR) antagonist [D-Lys3]-GHRP-6 (D-Lys3) was injected intraperitoneally in TBI rats after waking up. Molecular docking and pharmacological experiment with D-Lys3 were used to verify the pathway.

RESULTS

Twenty-six phytochemicals were identified based on LC-MS. FA, as the primary contributor of DCH, alleviated disruption of BBB and reduced brain edema, suppressed the secretion of proinflammatory factors, such as IL-6, IL-1β, TNF-α, as well as HPA axis-related hormones such as DA, NA, and 5-HT, and ghrelin, and BDNF by regulating the Ghrelin/GHSR pathway. These results were validated by GHSR receptor antagonist, as well as molecule docking.

CONCLUSIONS

Taken together, DCH, when prescribed for the treatment of TBI, has a certain degree of reasonableness. FA, as the main absorbed component, demonstrated a similar function to DCH in improving the blood-brain barrier, promoting neural recovery, and anti-inflammatory effects in TBI rats, primarily via modulating Ghrelin/GHSR.

Heart-brain axis in health and disease: role of innate and adaptive immunity

The importance of the brain-heart interaction has been increasingly recognized as a critical physiological axis that is altered in disease. In this review, we explore the intricate relationship between the central nervous system and cardiovascular health, focusing particularly on immunological mechanisms that influence the course of both neurological and cardiovascular diseases. While previous studies have established a key role of the autonomic nervous system (ANS) in linking brain and the heart, more recent studies have expanded our understanding of the multifaceted inter-organ interactions. As such, circulating mediators include immune cells of the adaptive and innate immune system and their secreted immunogenic factors have come into the focus as mediators along this bidirectional communication. Hence, in this review we briefly discuss the contribution of the ANS and then focus on innate and adaptive immune mechanisms along the heart-to-brain and brain-to-heart axes, illustrating how cardiovascular diseases affect cognitive functions and how brain pathologies lead to cardiac complications.

Combination therapies and other therapeutic approaches targeting the NLRP3 inflammasome and neuroinflammatory pathways: a promising approach for traumatic brain injury

OBJECTIVES

Traumatic brain injury (TBI) precipitates a neuroinflammatory cascade, with the NLRP3 inflammasome emerging as a critical mediator. This review scrutinizes the complex activation pathways of the NLRP3 inflammasome by underscoring the intricate interplay between calcium signaling, mitochondrial disturbances, redox imbalances, lysosomal integrity, and autophagy. It is hypothesized that a combination therapy approach-integrating NF-κB pathway inhibitors with NLRP3 inflammasome antagonists-holds the potential to synergistically dampen the inflammatory storm associated with TBI.

METHODS

A comprehensive analysis of literature detailing NLRP3 inflammasome activation pathways and therapeutic interventions was conducted. Empirical evidence supporting the concurrent administration of MCC950 and Rapamycin was reviewed to assess the efficacy of dual-action strategies compared to single-agent treatments.

RESULTS

Findings highlight potassium efflux and calcium signaling as novel targets for intervention, with cathepsin B inhibitors showing promise in mitigating neuroinflammation. Dual therapies, particularly MCC950 and Rapamycin, demonstrate enhanced efficacy in reducing neuroinflammation. Autophagy promotion, alongside NLRP3 inhibition, emerges as a complementary therapeutic avenue to reverse neuroinflammatory damage.

CONCLUSION

Combination therapies targeting the NLRP3 inflammasome and related pathways offer significant potential to enhance recovery in TBI patients. This review presents compelling evidence for the development of such strategies, marking a new frontier in neuroinflammatory research and therapeutic innovation.

Practice-Pattern Variation in Neurocritical Care Blood Pressure Control Reveals Opportunities for Improved Long-Term Hypertension Control

Background and Objectives

Uncontrolled hypertension is a risk factor of heart attack, stroke, dementia, and other conditions. In outpatients with hypertension, blood pressure (BP) may be controlled at only 30%-50% of visits depending on the population studied. Hospital admission is ideal for achieving guideline-directed BP targets, given the resource-intensive environment. We evaluated the relationship between BP control performance during neurocritical care and hospital admission and rates of uncontrolled hypertension at discharge and over the subsequent 2 years.

Methods

This two-center retrospective cohort included adults admitted with any neurologic illness to an neurosciences intensive care unit (NeuroICU) from April 2016 to December 2022, transferred to a neurology general care unit, and then discharged to home or rehabilitation. Hypertension was defined as systolic BP (SBP) ≥140 mm Hg or diastolic BP (DBP) ≥90 mm Hg. The primary outcomes were rates of hypertension at hospital discharge through 2 years after discharge. Multivariable logistic and generalized additive models were developed to assess the association between NeuroICU BP control and persistent hypertension, adjusting for baseline covariates, NeuroICU length of stay, performance measures quantifying BP goals, and antihypertensive medication intensity on transferring from the NeuroICU.

Results

Of 13,711 admissions, 10,836 met inclusion criteria and 3,075 (28.3%) were hypertensive at hospital discharge. Each 10-mm Hg SBP increase at NeuroICU transfer was associated with 1.60-fold increased odds of uncontrolled hypertension at discharge (95% CI 1.56-1.64). In multivariate analysis controlling for covariates, hypertension at transfer remained independently associated with hypertension at discharge (adjusted odds ratio 3.85, 95% CI 3.47-4.28). The association persisted through 24 months after discharge, even among those without a history of hypertension, among those admitted to the hospital normotensive, or when adjusting for antihypertensive therapy intensity. The association persisted across a range of principal diagnoses and across institutions, although practice-pattern variation yielded significant differences between institutions.

Discussion

Hypertension at NeuroICU transfer was independently associated with uncontrolled hypertension through hospital discharge and the subsequent 2 years, independent of patient diagnosis, medical history, institution, and treatment intensity. The initial hospitalization represents an opportunity to achieve and maintain guideline-directed BP targets to reduce secondary cerebrovascular events, dementia, and cardiovascular complications. Further studies are needed to determine whether improving rates of BP control at NeuroICU transfer and discharge leads to long-term improvements in BP control.

Concussions Are Associated With Increases in Blood Pressure and Cardiovascular Risk in American-Style Football Athletes

BACKGROUND

Concussions sustained during American-style football (ASF) participation are common. Whether concussions are associated with cardiovascular risk is unknown.

OBJECTIVES

The authors sought to determine whether concussions sustained during collegiate ASF participation lead to increases in systolic blood pressure (SBP) and acquired maladaptive cardiovascular phenotypes.

METHODS

In a longitudinal and case-controlled analysis, ASF athletes at 2 National Collegiate Athletic Association Division-I programs were followed for up to 2 years with cardiovascular assessments including BP, echocardiography, and vascular applanation tonometry. ASF athletes who sustained clinically diagnosed concussions were compared to weight and player position-matched controls without concussions.

RESULTS

Thirty-nine ASF athletes who sustained concussions (preconcussion baseline: [SBP] 129.6 ± 13.6 mm Hg) and 39 weight and player position-matched controls (preconcussion baseline: [SBP] 131.6 ± 13.1 mm Hg) were followed for 1 season postconcussion; 14 of these pairs were followed through 2 seasons. After 1 season, increased pulse wave velocity (PWV) (case Δ = 0.4 [0.2] m/s, P = 0.036; control Δ = -0.1 [0.1] m/s, P = 0.38) was observed among cases. Among the case and control pairs followed over 2 seasons, increased SBP (case Δ = 10.1 [3.6] mm Hg, P < 0.01; control Δ = 0.1 [3.2] mm Hg, P = 0.97) and diastolic blood pressure (case Δ = 8.2 [2.9] mm Hg, P < 0.01; control Δ = -4.1 [4.0] mm Hg, P = 0.30) and decreased É (case Δ = -2.8 [0.8] cm/s, P = 0.001; control Δ = -1.0 [0.8] cm/s, P = 0.21) were observed among cases. Over 1 season, concussions were associated with higher PWV (β = 0.33 [95% CI: 0.09-0.56], P = 0.007). Among athletes followed over 2 seasons, concussions were associated with higher PWV (β = 0.42 [95% CI: 0.05-0.78], P = 0.03), diastolic blood pressure (β = 5.89 [95% CI: 1.23-10.54], P = 0.01), LV mass index (β = 11.01 [95% CI: 6.13-15.90], P < 0.001), and lower É (β = -2.11 [95% CI: -3.27 to -0.95], P < 0.001).

CONCLUSIONS

Concussions sustained during collegiate ASF participation are independently associated with markers of cardiovascular risk and acquired maladaptive cardiovascular phenotypes. Clinical ASF concussion management strategies inclusive of careful BP surveillance may lead to early identification of hypertension.

Nasal anti-CD3 monoclonal antibody ameliorates traumatic brain injury, enhances microglial phagocytosis and reduces neuroinflammation via IL-10-dependent Treg-microglia crosstalk

Neuroinflammation plays a crucial role in traumatic brain injury (TBI), contributing to both damage and recovery, yet no effective therapy exists to mitigate central nervous system (CNS) injury and promote recovery after TBI. In the present study, we found that nasal administration of an anti-CD3 monoclonal antibody ameliorated CNS damage and behavioral deficits in a mouse model of contusional TBI. Nasal anti-CD3 induced a population of interleukin (IL)-10-producing regulatory T cells (Treg cells) that migrated to the brain and closely contacted microglia. Treg cells directly reduced chronic microglia inflammation and regulated their phagocytic function in an IL-10-dependent manner. Blocking the IL-10 receptor globally or specifically on microglia in vivo abrogated the beneficial effects of nasal anti-CD3. However, the adoptive transfer of IL-10-producing Treg cells to TBI-injured mice restored these beneficial effects by enhancing microglial phagocytic capacity and reducing microglia-induced neuroinflammation. These findings suggest that nasal anti-CD3 represents a promising new therapeutic approach for treating TBI and potentially other forms of acute brain injury.

Noncanonical feedback loop between "RIP3-MLKL" and "4EBP1-eIF4E" promotes neuronal necroptosis

Stroke is a leading risk factor for disability and death. Necroptosis is involved in stroke pathogenesis. However, the molecular mechanisms underlying necroptosis in stroke remain unclear. The mammalian target of rapamycin complex 1 (mTORC1) modulates necroptosis in the gut epithelium. Eukaryotic translation initiation factor 4E (eIF4E)-binding protein-1 (4EPB1) is one of the main downstream molecules of mTORC1. This study addresses the role of the 4EBP1-eIF4E pathway in necroptosis. The 4EBP1-eIF4E pathway was found to be activated in both necroptotic HT-22 and mouse middle cerebral artery occlusion (MCAO) models. Functionally, 4EBP1 overexpression, eIF4E knockdown, and eIF4E inhibition suppressed necroptosis, respectively. Furthermore, a positive feedback circuit was observed between the 4EBP1-eIF4E and receptor-interacting protein-3 (RIP3)-mixed lineage kinase domain-like protein (MLKL) pathways, in which RIP3-MLKL activates the 4EBP1-eIF4E pathway by degrading 4EBP1 and activating eIF4E. This in turn enhanced RIP3-MLKL pathway activation. The eIF4E activation derived from this loop may stimulate cytokine production, which is a key factor associated with necroptosis. Finally, using a mouse MCAO model, the application of eIF4E, RIP3, and MLKL inhibitors was found to have a regulatory mechanism similar to that in the in vitro study, reducing the infarct volume and improving neurological function in MCAO mice.

Extracranial Effects of Traumatic Brain Injury: A Narrative Review

BACKGROUND

Traumatic brain injury (TBI) is often associated with other injuries and comorbidities. However, even isolated TBI directly leads to dysfunction in multiple body systems outside the central nervous system. These extracranial effects of TBI target systems including the autonomic nervous, cardiovascular, renal, pulmonary, immune, gastrointestinal, and hemostasis systems, as well as causing significant alteration to systemic metabolism.

AIM

This review is intended to outline the effects of TBI on other body systems, and place these in context with treatment considerations for these patients.

SIGNIFICANCE

Systemic effects of TBI have implications for acute and critical care management of patients with TBI, including pharmacologic treatment. They also affect treatment decisions in chronic TBI care, as well as TBI-unrelated routine medical care for patients with chronic TBI. In addition, extracranial effects of TBI should be considered in research settings.

CONCLUSIONS

It is important for clinicians and researchers to be aware of these extracranial effects, and consider their effects on pathology, treatment decisions, and interpretation of research findings.

Reverse shock index multiplied by Glasgow coma scale (rSIG) to predict mortality in traumatic brain injury: systematic review and meta-analysis

OBJECTIVE

To determine whether the Reverse Shock Index multiplied by the Glasgow Coma Scale (rSIG) is a predictor of in-hospital mortality in patients with traumatic brain injury (TBI).

DESIGN

This is a systematic review and meta-analysis.

SETTING

A comprehensive search was conducted in five databases for studies published up to May 22, 2024, using a PECO strategy. Eight studies were identified for quantitative analysis and included in our meta-analysis.

PARTICIPANTS

The participants of the included primary studies.

INTERVENTIONS

Patients with a low rSIG as a predictor of in-hospital mortality in TBI.

MAIN VARIABLES OF INTEREST

rSIG, in-hospital mortality, TBI.

RESULTS

Our meta-analysis evaluated a total of eight observational studies encompassing 430,000 patients with TBI, observing 6,417 deaths (15%). After performing a sensitivity analysis, we found that patients with TBI and a low value of the reverse shock index multiplied by the Glasgow Coma Scale (rSIG) had a 24% higher risk of death (OR 1.24; 95% CI 1.12-1.38; I²: 96%). Furthermore, rSIG values were significantly higher in survivors compared to those who died (MD 7.72; 95% CI 1.86-13.58; I²: 99%).

Metabolic disorders after traumatic brain injury: a narrative review of systemic consequences

Traumatic brain injury (TBI) is characterized as a heterogeneous and pathological remodeling of brain physiology because of various external mechanisms, including blows, falls, and rapid acceleration and deceleration of the skull. Its pathophysiology consists of two distinct moments, beginning with a primary lesion resulting from the impact that evolves into a secondary lesion as biochemical and molecular mechanisms are activated. The severity and prognosis after TBI vary widely, depending on factors such as the site of the injury, the patient's premorbid history, and the severity of the injury, and can result in long-term sequelae impacting multiple organs and systems, with a reduction in the life expectancy of these individuals. A relevant point to be investigated is the correlation between metabolic syndrome (MS), defined as the combination of glucose intolerance, dyslipidemia, systemic arterial hypertension (SAH), and acute or chronic coronary heart disease, and the prognosis of these individuals after a TBI. Therefore, this review seeks to verify the correlation between the occurrence of MS in patients who have suffered TBI as a pre-existing comorbidity and whether it develops later, looking for evidence in studies based on animal models and cohort follow-ups of individuals who have suffered TBI in the short and long term to assess the prognosis presented.

Traumatic Brain Injury and Posttraumatic Stress Disorder Are Associated with Physical Health Burden Among Post-9/11 Women Veterans

Background: Little research focuses on physical health outcomes of traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) among post-9/11 women veterans (WVs). This study examined lifetime TBI, current PTSD, and their associations with biomarkers of cardiometabolic health, sleep, pain, and functional disability among post-9/11 WVs. Methods: WVs (n = 90) from the Translational Research Center for TBI and Stress Disorders longitudinal cohort study were included in this study. Gold standard clinician administered interviews assessed lifetime TBI (Boston Assessment of TBI-Lifetime) and current PTSD symptoms (Clinician-Administered PTSD Scale-IV). Objective measures of health included waist-hip ratio (WHR) and fasted blood biomarker (high density lipoprotein [HDL], low density lipoprotein [LDL], blood glucose, triglycerides) levels. Self-reported surveys assessed sleep, pain, and functional disability. Results: Just under two-thirds (58.9%) of WVs experienced a lifetime TBI, and just over half (53.3%) of this sample had a current PTSD diagnosis at the time of testing. Lifetime TBI was significantly associated with higher WHR, triglycerides levels, and worse pain and sleep (ps = <0.01 to 0.02; ds = 0.01 to 1.12). Current PTSD was significantly associated with higher WHR, lower HDL, and worse pain and sleep (ps = <0.01 to 0.02; ds = 0.009 to 1.19). PTSD was significantly associated with lower total functioning and each of its subdomains (βs = -0.58 to 0.63; ps = <0.001 to 0.02). Lifetime TBI was significantly associated with total functioning, mobility, and life/work (βs = -0.20 to 0.30; ps = <0.01 to 0.02). Conclusions: These findings highlight the importance of screening for lifetime TBI and cardiovascular disease for WVs and support transdiagnostic treatment approaches targeting physical health outcomes.

Traumatic brain injury: Symptoms to systems in the 21st century

Severe traumatic brain injury (TBI) is a devastating injury with a mortality of ∼ 25-30 %. Despite decades of high-quality research, no drug therapy has reduced mortality. Why is this so? We argue two contributing factors for the lack of effective drug therapies include the use of specific-pathogen free (SPF) animals for translational research and the flawed practice of single-nodal targeting for drug design. A revolution is required to better understand how the whole body responds to TBI, identify new markers of its progression, and discover new system-acting drugs to treat it. In this review, we present a brief history of TBI, discuss its system's pathophysiology and propose a new research strategy for the 21st century. TBI progression develops from injury signals radiating from the primary impact, which can cause local ischemia, hemorrhage, excitotoxicity, cellular depolarization, immune dysfunction, sympathetic hyperactivity, blood-brain barrier breach, coagulopathy and whole-body dysfunction. Metabolic reprograming of immune cells drives neuroinflammation and secondary injury processes. We propose if sympathetic hyperactivity and immune cell activation can be corrected early, cardiovascular function and endothelial-glycocalyx-mitochondrial coupling can be restored, and secondary injury minimized with improved patient outcomes. The therapeutic goal is to switch the injury phenotype to a healing phenotype by restoring homeostasis and maintaining sufficient tissue O2 delivery. We have been developing a small-volume fluid therapy comprising adenosine, lidocaine and magnesium (ALM) to treat TBI and have shown that it blunts the CNS-stress response, supports cardiovascular function and reduces secondary injury. Future research will investigate its suitability for human translation.

Traumatic Brain Injury and Risk of Incident Comorbidities

Importance

Traumatic brain injury (TBI) is associated with chronic medical conditions. Evidence from diverse clinical administrative datasets may improve care delivery.

Objective

To characterize post-TBI risk of incident neuropsychiatric and medical conditions in a California health care system administrative database and validate findings from a Massachusetts dataset.

Design, Setting, and Participants

In this cohort study, prospective longitudinal cohorts using data from 5 University of California health care settings between 2013 and 2022 were studied. Patients aged 18 years and older with mild (mTBI) or moderate to severe TBI (msTBI) were included. Unexposed individuals were propensity matched by age, race and ethnicity, sex, University of California site, insurance coverage, area deprivation index (ADI) score, and duration from index date to most recent clinical encounter. Patients with study comorbidities of interest before the index date were excluded. Data were analyzed August to October 2024.

Exposure

TBI.

Main Outcomes and Measures

International Classification of Diseases, Ninth Revision (ICD-9) and International Statistical Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes were used to identify patients with TBI and patients with up to 22 comorbidities within neurological, psychiatric, cardiovascular, and endocrine umbrella groupings. Cox proportional hazard models were used to generate yearly hazard ratios (HRs) from 6 months up to 10 years after a TBI. Models were further stratified by age and ADI score.

Results

The study consisted of 20 400 patients (9264 female [45.4%]; 1576 Black [7.7%], 3944 Latinx [19.3%], and 10 480 White [51.4%]), including 5100 patients with mTBI (median [IQR] age, 36.0 [25.0-51.0] years), 5100 patients with msTBI (median [IQR age, 35.0 [25.0-52.0] years), and 10 200 matched patients in the control group (median [IQR] age, 36.0 [25.0-51.0] years). By ADI score quintile, there were 2757 unexposed patients (27.0%), 1561 patients with mTBI (30.6%), and 1550 patients with msTBI (30.4%) in the lowest (1-2) quintiles and 1523 unexposed patients (14.9%), 769 patients with mTBI (15.1%), and 804 patients with msTBI (15.8%) in the highest quintiles (9-10). TBI of any severity was associated with increased risk of nearly all conditions (mTBI HRs ranged from 1.30; 95% CI, 1.07-1.57 for hypothyroidism to 4.06; 95% CI, 3.06-5.39 for dementia, and msTBI HRs ranged from 1.35; 95% CI, 1.12-1.62 for hypothyroidism to 3.45; 95% CI, 2.73-4.35 for seizure disorder). Separate age and ADI stratifications revealed patient populations at increased risk, including middle-age adults (ages 41-60 years), with increased risk of suicidality (mTBI: HR, 4.84; 95% CI, 3.01-7.78; msTBI: HR, 4.08; 95% CI, 2.51-6.62). Suicidality risk persisted for patients with mTBI in the high ADI subgroup (HR, 2.23; 95% CI, 1.36-3.66).

Conclusions and Relevance

In this cohort study, TBI was a risk factor associated with treatable incident neuropsychiatric and other medical conditions, validating similar findings from a Massachusetts dataset. Additional exploratory findings suggested varying demographic and regional risk patterns, which may generate causal hypotheses for further research and inform clinical surveillance strategies.

Concussion burden and later-life cardiovascular risk factors in former professional American-style football players

OBJECTIVE

Mid-life cardiovascular risk factors are associated with later cognitive decline. Whether repetitive head injury among professional athletes impacts cardiovascular risk is unknown. We investigated associations between concussion burden and postcareer hypertension, high cholesterol, and diabetes among former professional American-style football (ASF) players.

METHODS

In a cross-sectional study of 4080 professional ASF players conducted between January 2015 and March 2022, we used an mulitsymptom concussion symptom score (CSS) and the number of loss-of-consciousness (LOC) episodes as a single severe symptom to quantify football-related concussion exposure. Primary outcomes were hypertension, dyslipidemia, and diabetes, defined by current or recommended prescription medication use.

RESULTS

The prevalence of hypertension, high cholesterol, and diabetes among former players (52 ± 14 years of age) was 37%, 34%, and 9%. Concussion burden was significantly associated with hypertension (lowest vs. highest CSS quartile, odds ratio (OR) = 1.99; 95%CI: 1.33-2.98; p < 0.01) and high cholesterol (lowest vs. moderate CSS, OR = 1.46, 95%CI, 1.11-1.91; p < 0.01), but not diabetes. In fully adjusted models, the prevalence of multiple CVD was associated with CSS. These results were driven by younger former players (≤ 40 year of age) in which the odds of hypertension were over three times higher in those in the highest CSS quartile (OR = 3.29, 95%CI: 1.39-7.61; p = 0.01). Results were similar for LOC analyses.

INTERPRETATION

Prior concussion burden is associated with postcareer atherogenic cardiovascular risk profiles among former professional American football players.

Ameliorative properties of quercetin in the treatment of traumatic brain injury: a mechanistic review based on underlying mechanisms

Traumatic brain injury (TBI) is a leading cause of disability worldwide, with an estimated annual incidence of 27-69 million. TBI is a severe condition that can lead to high mortality rates and long-term cognitive, behavioral, and physical impairments in young adults. It is a significant public health concern due to the lack of effective treatments available. Quercetin, a natural flavonoid found in various fruits and vegetables, has demonstrated therapeutic potential with anti-inflammatory, antioxidant, and neuroprotective properties. Recently, some evidence has accentuated the ameliorating effects of quercetin on TBI. This review discusses quercetin's ability to reduce TBI-related damage by regulating many cellular and molecular pathways. Quercetin in vitro and in vivo studies exhibit promise in reducing inflammation, oxidative stress, apoptosis, and enhancing cognitive function post-TBI. Further clinical investigation into quercetin's therapeutic potential as a readily available adjuvant in the treatment of TBI is warranted in light of these findings. This review adds to our knowledge of quercetin's potential in treating TBI by clarifying its mechanisms of action.

Prevalence of Cardiovascular Conditions After Traumatic Brain Injury: A Comparison Between the Traumatic Brain Injury Model Systems and the National Health and Nutrition Examination Survey

BACKGROUND

The purpose of this study is to compare the prevalence of self-reported cardiovascular conditions among individuals with moderate to severe traumatic brain injury (TBI) to a propensity-matched control cohort.

METHODS AND RESULTS

A cross-sectional study described self-reported cardiovascular conditions (hypertension, congestive heart failure [CHF], myocardial infarction [MI], and stroke) from participants who completed interviews between January 2015 and March 2020 in 2 harmonized large cohort studies, the TBI Model Systems and the National Health and Nutrition Examination Survey. Mixed-effect logistic regression models were used to compare the prevalence of cardiovascular conditions after 1:1 propensity-score matching based on age, sex, race, ethnicity, body mass index, education level, and smoking status. The final sample was 4690 matched pairs. Individuals with TBI were more likely to report hypertension (odds ratio [OR], 1.18 [95% CI, 1.08-1.28]) and stroke (OR, 1.70 [95% CI, 1.56-1.98]) but less likely to report CHF (OR, 0.81 [95% CI, 0.67-0.99]) or MI (OR, 0.66 [95% CI, 0.55-0.79]). There was no difference in rate of CHF or MI for those ≤50 years old; however, rates of CHF and MI were lower in the TBI group for individuals >50 years old. Over 65% of individuals who died before the first follow-up interview at 1 year post-TBI were >50 years old, and those >50 years old were more likely to die of heart disease than those ≤50 years old (17.6% versus 8.6%).

CONCLUSIONS

Individuals with moderate to severe TBI had an increased rate of self-reported hypertension and stroke but lower rate of MI and CHF than uninjured adults, which may be due to survival bias.

High-salt diet induces microbiome dysregulation, neuroinflammation and anxiety in the chronic period after mild repetitive closed head injury in adolescent mice

The associations between human concussions and subsequent sequelae of chronic neuropsychiatric and cardiovascular diseases such as hypertension have been reported; however, little is known about the underlying biological processes. We hypothesized that dietary changes, including a high-salt diet, disrupt the bidirectional gut-brain axis, resulting in worsening neuroinflammation and emergence of cardiovascular and behavioural phenotypes in the chronic period after repetitive closed head injury in adolescent mice. Adolescent mice were subjected to three daily closed head injuries, recovered for 12 weeks and then maintained on a high-salt diet or a normal diet for an additional 12 weeks. Experimental endpoints were haemodynamics, behaviour, microglial gene expression (bulk RNA sequencing), brain inflammation (brain tissue quantitative PCR) and microbiome diversity (16S RNA sequencing). High-salt diet did not affect systemic blood pressure or heart rate in sham or injured mice. High-salt diet increased anxiety-like behaviour in injured mice compared to sham mice fed with high-salt diet and injured mice fed with normal diet. Increased anxiety in injured mice that received a high-salt diet was associated with microgliosis and a proinflammatory microglial transcriptomic signature, including upregulation in interferon-gamma, interferon-beta and oxidative stress-related pathways. Accordingly, we found upregulation of tumour necrosis factor-alpha and interferon-gamma mRNA in the brain tissue of high salt diet-fed injured mice. High-salt diet had a larger effect on the gut microbiome composition than repetitive closed head injury. Increases in gut microbes in the families Lachnospiraceae, Erysipelotrichaceae and Clostridiaceae were positively correlated with anxiety-like behaviours. In contrast, Muribaculaceae, Acholeplasmataceae and Lactobacillaceae were negatively correlated with anxiety in injured mice that received a high-salt diet, a time-dependent effect. The findings suggest that high-salt diet, administered after a recovery period, may affect neurologic outcomes following mild repetitive head injury, including the development of anxiety. This effect was linked to microbiome dysregulation and an exacerbation of microglial inflammation, which may be physiological targets to prevent behavioural sequelae in the chronic period after mild repetitive head injury. The data suggest an important contribution of diet in determining long-term outcomes after mild repetitive head injury.

Risk of Long-Term Ischemic Stroke in Patients With Traumatic Brain Injury and Incident Hypertension

Traumatic brain injury (TBI) is independently associated with hypertension and ischemic stroke. The goal of this study was to determine the interplay between TBI and incident hypertension in the occurrence of post-TBI stroke. This prospective study used a hospital-based registry to identify patients without pre-existing comorbidities. TBI patients (n = 3664) were frequency matched on age, sex, and race to non-TBI patients (n = 1848). Follow-up started 6 months post-TBI or study entry and extended up to 10 years. To examine hypertension's role in post-TBI stroke, we used logistic regression models to calculate the effect estimates for stroke in four exposure categories that included TBI or hypertension in isolation and in combination. Second, we calculated the conditional direct effect (CDE) of TBI in models that considered hypertension as intermediary. Third, we examined whether TBI effect was modified by antihypertensive medication use. The 10-year cumulative incidence of stroke was higher in the TBI group (4.7%) than the non-TBI group (1.3%; p < 0.001). TBI patients who developed hypertension had the highest risk of stroke (odds ratio [OR] = 4.83, 95% confidence interval [CI] = 2.53-9.23, p < 0.001). The combined effect estimates were less than additive, suggesting an overlapping biological pathway. The total effect of TBI (OR = 3.16, 95% CI = 1.94-5.16, p < 0.001) was higher than the CDE that accounted for hypertension (OR = 2.45, 95% CI = 0.93-6.47, p = 0.06). Antihypertensives attenuated the TBI effect, suggesting that the TBI effect on stroke is partially mediated through hypertension. TBI is an independent risk factor for long-term stroke, and the underlying biological pathway may partly operate through TBI-precipitated hypertension. These findings suggest that screening for hypertension may mitigate stroke risk in TBI.

Delayed Administration of an Angiotensin II Type 2 Receptor Agonist Promotes Functional Recovery of the Brain and Heart After Traumatic Brain Injury

Cardiac injury is a common complication following traumatic brain injury (TBI) that can lead to poor clinical outcomes. Angiotensin II type 2 receptor (AT2R) activation exerts protective roles in the brain and heart, yet its potential impact on TBI or TBI-induced cardiac deficits remains elusive. The goal of this study was to investigate the influence of AT2R activation on recovery after TBI-induced cognitive and cardiac injury using the selective nonpeptide AT2R agonist compound 21 (C21). TBI was induced by cortical impact injury in male adult C57BL/6J mice, and the mice received C21 (0.03 mg/kg, intraperitoneally) starting from 24 h after TBI and continuing once daily. C21 facilitated cognitive function recovery until 1 month after TBI. C21 alleviated blood-brain barrier leakage and brain edema and inhibited the expression of proinflammatory cytokines in the brain after 3 consecutive days of treatment. C21 improved cerebral blood flow after 1 month, although the lesion volume was not affected. C21 also reduced the expression of proinflammatory cytokines in the heart after a 3-day consecutive treatment. Meanwhile, C21 benefited cardiac function, as identified by increased left ventricular ejection fraction 1 month after TBI. In addition, C21 alleviated TBI-induced cardiac hypertrophy and fibrosis; however, blood pressure was not affected. Our results demonstrate that AT2R activation ameliorates TBI-induced neurological and cardiac deficits.

Therapeutic Potential of Cannabis: A Comprehensive Review of Current and Future Applications

Historically, cannabis has been valued for its pain-relieving, anti-inflammatory, and calming properties. Ancient civilizations like the Egyptians, Greeks, and Chinese medicines recognized their therapeutic potential. The discovery of the endocannabinoid system, which interacts with cannabis phytoconstituents, has scientifically explained how cannabis affects the human immune system, including the central nervous system (CNS). This review explores the evolving world of cannabis-based treatments, spotlighting its diverse applications. By researching current research and clinical studies, we probe into how cannabinoids like Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) help to manage conditions ranging from chronic pain, persistent inflammation, cancer, inflammatory bowel disease, and neurological disorders to even viral diseases such as Human Immunodeficiency virus (HIV), SARS-CoV-2. and the emerging monkeypox. The long-term recreational use of cannabis can develop into cannabis use disorder (CUD), and therefore, understanding the factors contributing to the development and maintenance of cannabis addiction, including genetic predisposition, neurobiological mechanisms, and environmental influences, will be timely. Shedding light on the adverse impacts of CUD underscores the importance of early intervention, effective treatment approaches, and public health initiatives to address this complex issue in an evolving landscape of cannabis policies and perceptions.