Pathophysiology of hypopituitarism in the setting of brain injury

Efficacy of biomarkers and imaging techniques for the diagnosis of traumatic brain injury: challenges and opportunities

Concussion is a pervasive health issue in the present day. Increased prevalence in recent years has indicated a need to improve the current understanding of minor traumatic brain injury (mTBI). Effort has been devoted to understanding the underlying pathophysiology of TBIs, but some mechanisms remain unknown. Potentially lethal secondary effects of concussion include second impact syndrome and chronic traumatic encephalopathy (CTE), introducing long-term considerations for the management of mTBI. Post-concussion syndrome is another long-term consequence of concussion and may be influenced by both neuroinflammation and hormonal imbalances resulting from head trauma. Genetically mutated apolipoprotein E may also contribute to the severity and persistence of concussion symptoms, perhaps even acting as a risk factor for CTE. As it stands, the diagnosis of concussion is nuanced, depending primarily on subjective diagnostic tools that incorporate patient-reported symptoms and neurocognitive tests. Diagnostic tools provide some assistance in concussion diagnosis, but still lack accuracy and inherently leave room for uncertainty. To mitigate some of this uncertainty, considerable research has been devoted to the development of methods to diagnose concussions objectively. Biomarkers such as S100 calcium binding protein B (S100B), glial fibrillary acidic protein (GFAP), neurofilament light protein (Nf-L), interleukin-6 (IL-6) and microRNAs (miRNAs) as well as imaging techniques including diffusion tensor imaging (DTI) and blood-oxygen level dependent functional magnetic resonance imaging (BOLD-fMRI) show great promise in this regard. This review aims to compile the relevant literature in these areas in the hopes of being used as a reference point for future research regarding concussions.

Assessment of the Sex Hormone Profile and Its Predictive Role in Consciousness Recovery Following Severe Traumatic Brain Injury

INTRODUCTION

Traumatic brain injuries (TBIs) are conditions affecting brain function caused by blunt or penetrating forces to the head. Symptoms may include confusion, impaired consciousness, coma, seizures, and focal or sensory neurological motor injuries.

OBJECTIVE

This study evaluated sex hormone profiles and their predictive role in returning consciousness after severe traumatic brain injury.

MATERIALS AND METHODS

We included 120 patients with TBIs and collected comprehensive information about each patient, including the cause of the trauma, age, gender, Glasgow Coma Scale (GCS) score, Injury Severity Score (ISS), and neuroradiological imaging data. The ISS was used to assess the severity of the trauma. At the same time, the lowest GCS score was recorded either before sedation and intubation in the emergency room or by emergency medical services personnel. For female participants, samples were collected during the luteal phase of the menstrual cycle (days 18 to 23).

RESULTS

The mean age of male patients was 33.40 years, ranging from 23 to 45 years, while female patients had an average age of 34.25 years, ranging from 25 to 48 years. The primary cause of injury for both genders was motor vehicle accidents. In male patients, testosterone levels were significantly higher in those classified as responsive (RC) compared to those non-responsive (NRC), with levels of 2.56 ± 0.47 ng/mL versus 0.81 ± 0.41 ng/mL (p = 0.003). A cut-off point of 1.885 ng/mL for testosterone levels in males was established, achieving a sensitivity and specificity of 86.7% and 86.7%, respectively. In female patients, progesterone levels were elevated in those who regained consciousness, measuring 1.80 ± 0.31 ng/mL compared to 0.62 ± 0.31 ng/mL (p = 0.012). A cut-off point of 1.335 ng/mL for progesterone levels in females was determined, with a sensitivity and specificity of 93.3% and 86.7%, respectively.

CONCLUSIONS

We can conclude that sex hormone levels in the acute phase of TBIs can vary between males and females. Notably, serum testosterone levels in males and progesterone levels in females with TBIs are significant prognostic factors for assessing the likelihood of regaining consciousness after such injuries. These findings underscore the importance of considering sex hormone profiles in TBI recovery prognosis.

Acute and Reversible Hypothalamic Symptoms in a Lateral Head Impact Mouse Model of Mild Traumatic Brain Injury

Central autonomic and endocrine dysfunctions following traumatic brain injury (TBI) are believed to involve the hypothalamus; however, underlying mechanisms are unknown. Although chronic deficits might be caused by irreversible tissue damage, various neuroendocrine and autonomic symptoms are only observed transiently, suggesting they might result from a temporary alteration in the activity of hypothalamic neurons. We therefore examined if a mouse model of mild TBI could induce reversible autonomic phenotypes and cause acute changes in c-Fos expression within corresponding regions of the hypothalamus. Adult C57Bl/6 male mice were lightly anesthetized with isoflurane and subjected to TBI by lateral head impact using a Gothenburg impactor. Mice treated the same way, but without the head impact served as controls (shams). We monitored body weight and core body temperature by infrared thermography and performed immunohistochemistry against c-Fos in various regions of the hypothalamus. We determined that a projectile velocity of 9 m/s significantly delayed recovery from the anesthesia without inducing skull fractures and signs of discomfort disappeared within 3 h, as assessed by grimace scale. Compared with shams, TBI mice displayed a rapid decrease in core body temperature which resolved within 48 h. Daily body weight gain was also significantly lower in TBI mice on the day following injury but recovered thereafter. c-Fos analysis revealed a significantly higher density of c-Fos-positive cells in the paraventricular nucleus and a significantly lower density in the median preoptic nucleus and medial preoptic area. We conclude that mild TBI induced by a single lateral head impact in mice at 9 m/s produces acute and reversible symptoms associated with hypothalamic dysfunction accompanied by significant changes in c-Fos expression within relevant areas of the hypothalamus. These findings support the hypothesis that a temporary alteration of neuronal activity may underlie the expression of reversible central autonomic and neuroendocrine symptoms.

A, Baba MS, Tramboo NA, Shah ZA, Lone AA, Hafeez I. Anterior pituitary hormone dysfunction among individuals with complete heart block requiring pacemaker

Background & objectives Neuronal hypoxia associated with conditions like traumatic brain injury and cardiac tachyarrhythmia has been implicated in causing hypopituitarism. Individuals with complete heart block (CHB) may be predisposed to develop anterior pituitary hormone dysfunction in the long term. The objective of this study was to investigate anterior pituitary hormone functions in individuals after CHB. Methods This prospective cohort study included 30 individuals (21 men and 9 women) with CHB requiring pacemaker implantation, who were evaluated at admission and then at a mean follow up of 12.4 ± 2.2 months to look for development of any degree of hypopituitarism. In addition to the measurement of hormones like follicle-stimulating hormone (FSH), luteinising hormone (LH), thyroid stimulating hormone (TSH), total tetra iodothyronines (TT4), free tetraiodothyronines (FT4), cortisol, insulin-like growth factor-1 (IGF-1), testosterone and estradiol, a fixed-dose glucagon stimulation test (GST) was performed to assess growth hormone (GH) and adrenocorticotrophic hormone (ACTH) axis. Results The mean age of the participants was 64.9 ± 11.3 yr. At follow up evaluation, 17 (56.7%) had low serum IGF-1, and among them, seven (23%) had growth hormone deficiency (GHD) (peak GH <1.0 ng/ml after GST). Six participants (20%) had ACTH deficiency (peak cortisol <9 ug/dl after GST) and one had TSH deficiency. None had prolactin (PRL) or gonadotropin deficiency. Overall, hormone deficiencies were observed in nine patients (30%). Interpretation & conclusions This pilot study detected loss of anterior pituitary hormones in a significant number of individuals of CHB at 12 months follow up. Unrecognised hypopituitarism may have resulted in significant morbidity and mortality in these individuals.

Acute neuroendocrine changes after traumatic brain injury

Introduction

Post-traumatic hypopituitarism (PTHP) is a significant, but often neglected consequence of traumatic brain injury (TBI).

Research question

We aimed to provide a comprehensive overview of epidemiology, pathophysiology, clinical features and diagnostic approaches of PTHP.

Materials and methods

MEDLINE, EMBASE, Cochrane Library and Web of Science were searched. 45 articles of human studies evaluating acute endocrine changes following mild, moderate and severe TBI were selected.

Results

Severity of TBI seems to be the most important risk factor of PTHP. Adrenal insufficiency (AI) was present in 10% of TBI patients (prevalence can be as high as 50% after severe TBI), and hypocortisolemia is a predictor of mortality and long-term hypopituitarism. Suppression of the thyroid axis in 2-33% of TBI patients may be an independent predictor of adverse neurological outcome, as well. 9-36% of patients with severe TBI exhibit decreased function of the somatotrophic axis with a divergent effect on the central nervous system. Arginine-Vasopressin (AVP) deficiency is present in 15-51% of patients, associated with increased mortality and unfavorable outcome. Due to shear and injury of the stalk hyperprolactinemia is relatively common (2-50%), but it bears little clinical significance. Sex hormone levels remain within normal values.

Discussion and conclusion

PTHP occurs frequently after TBI, affecting various axis and determining patients' outcome. However, evidence is scarce regarding exact epidemiology, diagnosis, and effective clinical application of hormone substitution. Future studies are needed to identify patients at-risk, determine the optimal timing for endocrine testing, and refine diagnostic and treatment approaches to improve outcome.

A comprehensive review of the new FIGO classification of ovulatory disorders

BACKGROUND

The World Health Organization (WHO) system for the classification of disorders of ovulation was produced 50 years ago and, by international consensus, has been updated by the International Federation of Gynecology and Obstetrics (FIGO).

OBJECTIVE AND RATIONALE

This review outlines in detail each component of the FIGO HyPO-P (hypothalamic, pituitary, ovarian, PCOS) classification with a concise description of each cause, and thereby provides a systematic method for diagnosis and management.

SEARCH METHODS

We searched the published articles in the PubMed database in the English-language literature until October 2022, containing the keywords ovulatory disorders; ovulatory dysfunction; anovulation, and each subheading in the FIGO HyPO-P classification. We did not include abstracts or conference proceedings because the data are usually difficult to assess.

OUTCOMES

We present the most comprehensive review of all disorders of ovulation, published systematically according to the logical FIGO classification.

WIDER IMPLICATIONS

Improving the diagnosis of an individual's ovulatory dysfunction will significantly impact clinical practice by enabling healthcare practitioners to make a precise diagnosis and plan appropriate management.

Endocrine Dysfunction After Traumatic Brain Injury: An Ignored Clinical Syndrome?

Traumatic brain injury (TBI) incurs substantial health and economic burden, as it is the leading reason for death and disability globally. Endocrine abnormalities are no longer considered a rare complication of TBI. The reported prevalence is variable across studies, depending on the time frame of injury, time and type of testing, and variability in hormonal values considered normal across different studies. The present review reports evidence on the endocrine dysfunction that can occur after TBI. Several aspects, including the pathophysiological mechanisms, clinical consequences/challenges (in the acute and chronic phases), screening and diagnostic workup, principles of therapeutic management, and insights on future directions/research agenda, are presented. The management of hypopituitarism following TBI involves hormonal replacement therapy. It is essential for health care providers to be aware of this complication because at times, symptoms may be subtle and may be mistaken to be caused by brain injury itself. There is a need for stronger evidence for establishing recommendations for optimum management so that they can be incorporated as standard of care in TBI management.

Prognostic significance of prolonged corrected QT interval in cerebral contusion

Background & objectives

Cerebral contusion (CC) results in a release of catecholamines, autonomic dysfunction and neural stimulation that can lead to a number of cardiac adverse events, so it is critical to determine these. So the objective of this study was to investigate the prognostic significance of electrocardiographic changes, particularly the effects of a prolonged corrected QT (QTc) interval in CC.

Methods

In this retrospective cohort study, 110 patients with CC were evaluated. Age, sex, concomitant diseases, Glasgow Coma Scale on admission, radiological assessment of the contusion (location, size, course and presence of cerebral oedema), need for surgical intervention, length of hospital stay and the extended Glasgow Outcome Scale (GOS-E) were statistically analysed within the QTc interval by routine electrocardiography (ECG) on admission.

Results

The prolonged QTc interval was found to be associated with a higher incidence of cerebral oedema and a significantly higher risk of needing surgery. Patients with a prolonged QTc interval had a significantly larger contusion volume, greater midline shift and longer hospital stay, so their GOS-E score was significantly lower. A prolonged QTc interval on admission resulted in a hospital stay of more than eight days (sensitivity: 0.97 and specificity: 0.86), a higher risk of midline shift of more than 0.45 cm (P=0.006, sensitivity: 0.80 and specificity: 0.99) and a GOS-E score of <7 (sensitivity: 0.97 and specificity: 0.85).

Interpretation & conclusions

ECG changes on admission showing a prolonged QTc interval have prognostic significance in CC. This simple and easily applicable information should be taken into consideration at the time of clinical decision making which may prevent an adverse events survivor.

Chronic Anterior Pituitary Dysfunction Following Traumatic Head Injury: Prospective Study in Hospital Sultanah Aminah Johor Bahru, Malaysia

Background

Hypopituitarism following traumatic brain injury (TBI) is not rare however most patients were left undiagnosed and untreated. Association of post TBI hypopituitarism causing neurobehavioural and quality of life impairment. The aim of the study is to determine the incidence of the chronic anterior pituitary deficiency in patients with traumatic brain injury. Subsequently determine the risk factor and the outcome of the patient with chronic anterior pituitary dysfunction.

Methods

This is single centre cross-sectional study involved 105 traumatic head injury patients under the Neurosurgical Department Hospital Sultanah Aminah, Johor Bahru, Malaysia. The primary investigator will do an interview and the patients will be asked question to complete a questioner from SF-36 (36 questions). Subsequently, consent for participation will be taken and blood sampling will be done.

Results

Thirty-three patients were noted to have anterior pituitary dysfunction. The mean age was 36.97 ± 12.96 years old. Twenty-seven patients (32.5%) were male and six patients were female (27.3%). Chronic anterior pituitary dysfunction in patients with a severe traumatic head injury around 47.1% (23 patients), as compared to a moderate head injury (8 patients, 38.1%) and 2 sustained mild head injury (5.6%). The mean duration after the onset of trauma was 10.3 ± 1.79 months. All patient with anterior pituitary dysfunction had positive CT brain findings with 22 had subarachnoid haemorrhage (SAH) at the basal cistern and 27 patients had a base of skull fracture, where 52.1% of the patient underwent surgical intervention, 84.8% involved one axis and another 5 patients had two axes involved. Severity of the head injury (P < 0.001), prolonged duration of hospital stay (P = 0.014), radiological findings of a base of skull fracture (P < 0.001) and presence of SAH at basal cistern (P < 0.001) was significantly associated with pituitary dysfunction. The patient with anterior pituitary dysfunction has the lower 36-item Short Form Survey (SF-36) marks 56.3 ± 10.3.

Conclusion

The prevalence of hypopituitarism was 31%. Indicators are increased TBI severity, prolonged hospitalisation and positive finding in radiological assessment. Post-traumatic chronic anterior pituitary dysfunction also related with poor quality of life as showed by low SF-36 marks.

Endocrine Abnormalities in Children With Traumatic Brain Injury at a Tertiary Care Center

Objective Accidental traumatic brain injury (TBI) can lead to severe complications such as endocrine abnormalities and long-term morbidities and can negatively impact patient lives. These conditions are also associated with a high cost of treatment over a lifetime, a significant concern in low-to-middle-income countries (LMICs). In Pakistan, the prevalence of children with endocrine abnormalities secondary to TBI remains largely unexplored. We conducted a retrospective cross-sectional study to estimate the burden of endocrine abnormalities due to TBI among children in our population. Methods Twenty patients previously admitted with head injury between September and October 2019 were retrospectively reviewed with tests for baseline serum sodium, plasma osmolality, cortisol, adrenocorticotropin (ACTH), free thyroxine (fT4), growth hormone (GH), insulin growth factor-1 (IGF-1), follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), prolactin, estradiol, and testosterone. Data were collated from the electronic Health and Information Management System (HIMS) and analyzed using SPSS v25. Chi-square and t-tests were used to identify associations between variable groups. Outcomes of interest included correlations between hormonal levels and demographic factors, interventions and hormonal levels, and complication rates and hormonal levels. Results Our study reports three (15% of the total cohort) patients with pituitary hormone deficits (two with low IGF-1 and one with low TSH). High serum IGF-1 and ACTH levels were also observed in three (15%) children. High IGF-1 was associated with female gender (p=0.007), mechanical ventilation (p=0.038), and falls (p=0.028). IGF-1 (p=0.035) and GH (p=0.049) levels were associated with improvement in Extended Glasgow Outcome Scale (GOS-E) score. Testosterone was positively correlated with a high percentile for height (p=0.005) and GOS-E scores on follow-up (p=0.030). High testosterone levels (592.12 ± 102.28 ng/dl) were associated with good functional outcomes in post-pubescent patients (p<0.05). Serum fT4 was linked with a high GOS-E score at discharge in prepubescent patients (p=0.034). Neurosurgical decompression was the only risk factor for hormone deficiency, comprising 67% of the group with hormone deficiencies (p=0.028). The learning difficulties were observed exclusively in children with hormonal deficiencies (7 patients, p=0.000).  Conclusion Hormonal dysfunction due to TBI in children can lead to poor outcomes. High serum IGF-1, testosterone, and free T4 levels were associated with improved functional outcomes in children with TBI. Limited follow-up and resources in LMICs are significant barriers to addressing the morbidity associated with these conditions and need to be addressed at a health policy level.

A consensus on optimization of care in patients with growth hormone deficiency and mild traumatic brain injury

OBJECTIVE/DESIGN

Approximately 2.9 million children and adults in the US experience traumatic brain injuries (TBIs) annually, most of which are considered mild. TBI can induce varying consequences on pituitary function, with growth hormone deficiency (GHD) among the more commonly reported conditions. Panels of pediatric and adult endocrinologists, neurologists, physical medicine and rehabilitation specialists, and neuropsychologists convened in February and October 2020 to discuss ongoing challenges and provide strategies for detection and optimal management of patients with mild TBI and GHD.

RESULTS

Difficulties include a low rate of seeking medical attention in the population, suboptimal screening tools, cost and complexity of GHD testing, and a lack of consensus regarding when to test or retest for GHD. Additionally, referrals to endocrinologists from other specialists are uncommon. Recommendations from the panels for managing such patients included multidisciplinary guidelines on the diagnosis and management of post-TBI GHD and additional education on long-term metabolic and probable cognitive benefits of GH replacement therapy.

CONCLUSION

As patients of all ages with mild TBI may develop GHD and/or other pituitary deficiencies, a multidisciplinary approach to provide education to endocrinologists, neurologists, neurosurgeons, traumatologists, and other providers and guidelines for the early identification and management of persistent mild TBI-related GHD are urgently needed.

Hypothalamic-Pituitary and Other Endocrine Surveillance Among Childhood Cancer Survivors

Endocrine disorders in survivors of childhood, adolescent, and young adult (CAYA) cancers are associated with substantial adverse physical and psychosocial effects. To improve appropriate and timely endocrine screening and referral to a specialist, the International Late Effects of Childhood Cancer Guideline Harmonization Group (IGHG) aims to develop evidence and expert consensus-based guidelines for healthcare providers that harmonize recommendations for surveillance of endocrine disorders in CAYA cancer survivors. Existing IGHG surveillance recommendations for premature ovarian insufficiency, gonadotoxicity in males, fertility preservation, and thyroid cancer are summarized. For hypothalamic-pituitary (HP) dysfunction, new surveillance recommendations were formulated by a guideline panel consisting of 42 interdisciplinary international experts. A systematic literature search was performed in MEDLINE (through PubMed) for clinically relevant questions concerning HP dysfunction. Literature was screened for eligibility. Recommendations were formulated by drawing conclusions from quality assessment of all evidence, considering the potential benefits of early detection and appropriate management. Healthcare providers should be aware that CAYA cancer survivors have an increased risk for endocrine disorders, including HP dysfunction. Regular surveillance with clinical history, anthropomorphic measures, physical examination, and laboratory measurements is recommended in at-risk survivors. When endocrine disorders are suspected, healthcare providers should proceed with timely referrals to specialized services. These international evidence-based recommendations for surveillance of endocrine disorders in CAYA cancer survivors inform healthcare providers and highlight the need for long-term endocrine follow-up care in subgroups of survivors and elucidate opportunities for further research.

Recurrent hypoglycemic seizure as a presenting symptom of post-TBI hypopituitarism in children: a case report, review and proposed protocol

OBJECTIVES

Post-traumatic brain injury hypopituitarism is a common unrecognized condition in children after head injury. Due to its similarity of clinical symptoms with those of head trauma, clinical diagnosis of post-TBI hypopituitarism is challenging. To date, there is no standardized screening protocol for children with history of brain injury. This article demonstrates a case of 14-year-old boy with severe head trauma who developed refractory seizures with episodic hypoglycemia and weight loss. We aimed to focus on the prevalence, clinical courses and clinical implementations of each hormonal axis in children with post-traumatic brain injury hypopituitarism. We also aim to raise awareness of this condition to pediatricians in light of enhancing patient care.

METHODS

We have searched for original articles, published in English between year 2000 and 2021. There are 20 related articles, authors reviewed all the articles independently.

RESULTS

Prevalence of post-traumatic hypopituitarism ranges from 5-57% in children. Growth hormone is the most commonly affected hormone. The highest prevalence is 42.3% at more than 12 months after the brain injury. The symptoms and severity range from asymptomatic to requiring long-term hormonal therapy. Although normalization of pituitary function is demonstrated at various times after the injury, hormone replacement therapy is still required in some patients.

CONCLUSIONS

This is the first report that demonstrates a presenting symptom of hypopituitarism mimic traumatic brain symptoms which result in it being overlooked. This case emphasizes the need to develop pituitary function screening protocols for children with TBI. We have proposed our pituitary screening protocol for children with TBI in this article.

Relationship between Anterior Pituitary Volume and IGF-1 Serum Levels in Soldiers with Mild Traumatic Brain Injury History

PURPOSE

A high mild traumatic brain injury (mTBI) incidence rate exists in military and sport. Hypopituitarism is an mTBI sequela; however, few studies have examined this phenomenon in those with an mTBI history. This cross-sectional study of Special Operations Forces combat soldiers aimed 1) to relate anterior pituitary gland volumes (actual and normalized) to insulin-like growth factor 1 (IGF-1) concentrations, 2) to examine the effect of mTBI history on anterior pituitary gland volumes (actual and normalized) and IGF-1 concentrations, and 3) to measure the odds of demonstrating lower anterior pituitary gland volumes (actual and normalized) or IGF-1 concentrations if self-reporting mTBI history.

METHODS

Anterior pituitary gland volumes were manually segmented from T1-weighted 3D brain MRI sequences; IGF-1 serum concentrations were quantified using commercial enzyme-linked immunosorbent assays. Correlations and linear regression were used to determine the association between IGF-1 serum concentration and anterior pituitary gland volume (n = 74). Independent samples t-tests were used to compare outcomes between mTBI groups and logistic regression models were fit to test the odds of demonstrating IGF-1 concentration or anterior pituitary volume less than sample median based on mTBI group (n = 54).

RESULTS

A significant linear relationship between the subjects' anterior pituitary gland volumes and IGF-1 concentrations (r72 = 0.35, P = 0.002) was observed. Soldiers with mTBI history had lower IGF-1 concentrations (P < 0.001) and lower anterior pituitary gland volumes (P = 0.037) and were at greater odds for IGF-1 serum concentrations less than the sample median (odds ratio = 5.73; 95% confidence interval = 1.77-18.55).

CONCLUSIONS

Anterior pituitary gland volume was associated with IGF-1 serum concentrations. Mild TBI history may be adversely associated with anterior pituitary gland volumes and IGF-1 concentrations. Longitudinal IGF-1 and anterior pituitary gland monitoring may be indicated in those who report one or more mTBI.

The role of the stress system in recovery after traumatic brain injury: A tribute to Bruce S. McEwen

Traumatic brain injury (TBI) represents a major public health concern. Although the majority of individuals that suffer mild-moderate TBI recover relatively quickly, a substantial subset of individuals experiences prolonged and debilitating symptoms. An exacerbated response to physiological and psychological stressors after TBI may mediate poor functional recovery. Individuals with TBI can suffer from poor stress tolerance, impairments in the ability to evaluate stressors, and poor initiation (and cessation) of neuroendocrine stress responses, all of which can exacerbate TBI-mediated dysfunction. Here, we pay tribute to the pioneering neuroendocrinologist Dr. Bruce McEwen by discussing the ways in which his work on stress physiology and allostatic loading impacts the TBI patient population both before and after their injuries. Specifically, we will discuss the modulatory role of hypothalamic-pituitary-adrenal axis responses immediately after TBI and later in recovery. We will also consider the impact of stressors and stress responses in promoting post-concussive syndrome and post-traumatic stress disorders, two common sequelae of TBI. Finally, we will explore the role of early life stressors, prior to brain injuries, as modulators of injury outcomes.

Lupeol Treatment Attenuates Activation of Glial Cells and Oxidative-Stress-Mediated Neuropathology in Mouse Model of Traumatic Brain Injury

Traumatic brain injury (TBI) signifies a major cause of death and disability. TBI causes central nervous system (CNS) damage under a variety of mechanisms, including protein aggregation, mitochondrial dysfunction, oxidative stress, and neuroinflammation. Astrocytes and microglia, cells of the CNS, are considered the key players in initiating an inflammatory response after injury. Several evidence suggests that activation of astrocytes/microglia and ROS/LPO have the potential to cause more harmful effects in the pathological processes following traumatic brain injury (TBI). Previous studies have established that lupeol provides neuroprotection through modulation of inflammation, oxidative stress, and apoptosis in Aβ and LPS model and neurodegenerative disease. However, the effects of lupeol on apoptosis caused by inflammation and oxidative stress in TBI have not yet been investigated. Therefore, we explored the role of Lupeol on antiapoptosis, anti-inflammatory, and antioxidative stress and its potential mechanism following TBI. In these experiments, adult male mice were randomly divided into four groups: control, TBI, TBI+ Lupeol, and Sham group. Western blotting, immunofluorescence staining, and ROS/LPO assays were performed to investigate the role of lupeol against neuroinflammation, oxidative stress, and apoptosis. Lupeol treatment reversed TBI-induced behavioral and memory disturbances. Lupeol attenuated TBI-induced generation of reactive oxygen species/lipid per oxidation (ROS/LPO) and improved the antioxidant protein level, such as nuclear factor erythroid 2-related factor 2 (Nrf2) and heme-oxygenase 1 (HO-1) in the mouse brain. Similarly, our results indicated that lupeol treatment inhibited glial cell activation, p-NF-κB, and downstream signaling molecules, such as TNF-α, COX-2, and IL-1β, in the mouse cortex and hippocampus. Moreover, lupeol treatment also inhibited mitochondrial apoptotic signaling molecules, such as caspase-3, Bax, cytochrome-C, and reversed deregulated Bcl2 in TBI-treated mice. Overall, our study demonstrated that lupeol inhibits the activation of astrocytes/microglia and ROS/LPO that lead to oxidative stress, neuroinflammation, and apoptosis followed by TBI.

Endocrine Responses to Sport-Related Brain Injury in Female Athletes: A Narrative Review and a Call for Action

Sport-related brain injury (SRBI) occurs when a blow to the head causes the brain to move back and forth in the skull, and can lead to neuroendocrine dysfunction. Research has shown that males and females experience and recover from SRBI differently, yet most of what is known regarding diagnosis, treatment, and recovery of SRBI is based on male normative data even though females meet or exceed incidence numbers of SRBIs compared to those of males. Females also have been known to have worse outcomes and a greater number of symptoms following SRBI than males. Research is limited as to why females have worse outcomes, but sex hormones have been suggested as a potential reason. SRBI may cause a dysregulation of the hypothalamic–pituitary–gonadal (HPG) axis, which is responsible for regulating the sex hormones estrogen and progesterone. Initial research has shown that SRBI may suppress estrogen and progesterone, and the concentration of these sex hormones could be indicative of injury severity and recovery trajectory. This review discusses the sex-specific differences in SRBI and also the future direction of research that is needed in order to identify the repercussions of SRBIs for female athletes, which will eventually lead to better clinical treatment, sideline care, and recovery profiles.

Neuroinflammation and Hypothalamo-Pituitary Dysfunction: Focus of Traumatic Brain Injury

The incidence of traumatic brain injury (TBI) has increased over the last years with an important impact on public health. Many preclinical and clinical studies identified multiple and heterogeneous TBI-related pathophysiological mechanisms that are responsible for functional, cognitive, and behavioral alterations. Recent evidence has suggested that post-TBI neuroinflammation is responsible for several long-term clinical consequences, including hypopituitarism. This review aims to summarize current evidence on TBI-induced neuroinflammation and its potential role in determining hypothalamic-pituitary dysfunctions.

Risk factors and predictive model of adrenocortical insufficiency in patients with traumatic brain injury

BACKGROUND

Neuroendocrine dysfunction after traumatic brain injury (TBI) has received increased attention due to its impact on the recovery of neural function. The purpose of this study is to investigate the incidence and risk factors of adrenocortical insufficiency (AI) after TBI to reveal independent predictors and build a prediction model of AI after TBI.

METHODS

Enrolled patients were grouped into the AI and non-AI groups. Fourteen preset impact factors were recorded. Patients were regrouped according to each impact factor as a categorical variable. Univariate and multiple logistic regression analyses were performed to screen the related independent risk factors of AI after TBI and develop the predictive model.

RESULTS

A total of 108 patients were recruited, of whom 34 (31.5%) patients had AI. Nine factors (age, Glasgow Coma Scale [GCS] score on admission, mean arterial pressure [MAP], urinary volume, serum sodium level, cerebral hernia, frontal lobe contusion, diffuse axonal injury [DAI], and skull base fracture) were probably related to AI after TBI. Three factors (urinary volume [X ₄], serum sodium level [X ₅], and DAI [X ₈]) were independent variables, based on which a prediction model was developed (logit P= -3.552+2.583X ₄+2.235X ₅+2.269X ₈).

CONCLUSIONS

The incidence of AI after TBI is high. Factors such as age, GCS score, MAP, urinary volume, serum sodium level, cerebral hernia, frontal lobe contusion, DAI, and skull base fracture are probably related to AI after TBI. Urinary volume, serum sodium level, and DAI are the independent predictors of AI after TBI.

Distant Organ Damage in Acute Brain Injury

Acute brain injuries pose a great threat to global health, having significant impact on mortality and disability. Patients with acute brain injury may develop distant organ failure, even if no systemic diseases or infection is present. The severity of non-neurologic organs' dysfunction depends on the extremity of the insult to the brain. In this comprehensive review we sought to describe the organ-related consequences of acute brain injuries. The clinician should always be aware of the interplay between central nervous system and non-neurological organs, that is constantly present. Cerebral injury is not only a brain disease, but also affects the body as whole, and thus requires holistic therapeutical approach.

Evidence Limitations in Determining Sexually Dimorphic Outcomes in Pediatric Post-Traumatic Hypopituitarism and the Path Forward

Neuroendocrine dysfunction can occur as a consequence of traumatic brain injury (TBI), and disruptions to the hypothalamic-pituitary axis can be especially consequential to children. The purpose of our review is to summarize current literature relevant to studying sex differences in pediatric post-traumatic hypopituitarism (PTHP). Our understanding of incidence, time course, and impact is constrained by studies which are primarily small, are disadvantaged by significant methodological challenges, and have investigated limited temporal windows. Because hormonal changes underpin the basis of growth and development, the timing of injury and PTHP testing with respect to pubertal stage gains particular importance. Reciprocal relationships among neuroendocrine function, TBI, adverse childhood events, and physiological, psychological and cognitive sequelae are underconsidered influencers of sexually dimorphic outcomes. In light of the tremendous heterogeneity in this body of literature, we conclude with the common path upon which we must collectively arrive in order to make progress in understanding PTHP.

Alterations of the GH/IGF-I Axis and Gut Microbiome after Traumatic Brain Injury: A New Clinical Syndrome?

CONTEXT

Pituitary dysfunction with abnormal growth hormone (GH) secretion and neurocognitive deficits are common consequences of traumatic brain injury (TBI). Recognizing the comorbidity of these symptoms is of clinical importance; however, efficacious treatment is currently lacking.

EVIDENCE ACQUISITION

A review of studies in PubMed published between January 1980 to March 2020 and ongoing clinical trials was conducted using the search terms "growth hormone," "traumatic brain injury," and "gut microbiome."

EVIDENCE SYNTHESIS

Increasing evidence has implicated the effects of TBI in promoting an interplay of ischemia, cytotoxicity, and inflammation that renders a subset of patients to develop postinjury hypopituitarism, severe fatigue, and impaired cognition and behavioral processes. Recent data have suggested an association between abnormal GH secretion and altered gut microbiome in TBI patients, thus prompting the description of a hypothesized new clinical syndrome called "brain injury associated fatigue and altered cognition." Notably, these patients demonstrate distinct characteristics from those with GH deficiency from other non-TBI causes in that their symptom complex improves significantly with recombinant human GH treatment, but does not reverse the underlying mechanistic cause as symptoms typically recur upon treatment cessation.

CONCLUSION

The reviewed data describe the importance of alterations of the GH/insulin-like growth factor I axis and gut microbiome after brain injury and its influence in promoting neurocognitive and behavioral deficits in a bidirectional relationship, and highlight a new clinical syndrome that may exist in a subset of TBI patients in whom recombinant human GH therapy could significantly improve symptomatology. More studies are needed to further characterize this clinical syndrome.

Prevalence of hypopituitarism and quality of life in survivors of post-traumatic brain injury

BACKGROUND

Hypopituitarism is a recognized sequela of traumatic brain injury (TBI) and may worsen the quality of life (QoL) in survivors.

AIMS

To assess the prevalence of post-traumatic hypopituitarism (PTHP) and growth hormone deficiency (GHD), and determine their correlation with QoL.

METHODS

Survivors of moderate to severe TBI were recruited from two Algerian centres. At 3 and 12 months, pituitary function was evaluated using insulin tolerance test (ITT), QoL by growth hormone deficiency in adults' questionnaire (QoL-AGHDA), and 36-item short-form (SF-36) health survey.

RESULTS

Of 133 (M: 128; F: 5) patients aged 18-65 years, PTHP and GHD were present at 3 and 12 months in 59 (44.4%) and 23 (17.29%), 41/116 (35.3%) and 18 (15.5%). Thirteen patients with GHD at 3 months tested normally at 12 months, while 9 had become GHD at 12 months. At 3 and 12 months, peak cortisol was < 500 nmol/L) in 39 (29.3%) and 29 (25%) patients, but <300 nmol/L in only five and seven. Prevalence for gonadotrophin deficiency was 6.8/8.6%, hypo- and hyperprolactinaemia 6.8/3.8% and 5.2/8.6%, and thyrotrophin deficiency 1.5/0.9%. Mean scores for QoL-AGHDA were higher in patients with PTHP at 3 and 12 months: 7.07 vs 3.62 (P = .001) and in patients with GHD at 12 months: 8.72 vs 4.09 (P = .015). Mean SF-36 scores were significantly lower for PTHP at 3 months.

CONCLUSION

Prevalence of PTHP and GHD changes with time. AGHDA measures QoL in GHD more specifically than SF-36. Full pituitary evaluation and QoL-AGHDA 12 months after TBI are recommended.

Traumatic brain injuries induced pituitary dysfunction: a call for algorithms

Traumatic brain injury affects many people each year, resulting in a serious burden of devastating health consequences. Motor-vehicle and work-related accidents, falls, assaults, as well as sport activities are the most common causes of traumatic brain injuries. Consequently, they may lead to permanent or transient pituitary insufficiency that causes adverse changes in body composition, worrisome metabolic function, reduced bone density, and a significant decrease in one's quality of life. The prevalence of post-traumatic hypopituitarism is difficult to determine, and the exact mechanisms lying behind it remain unclear. Several probable hypotheses have been suggested. The diagnosis of pituitary dysfunction is very challenging both due to the common occurrence of brain injuries, the subtle character of clinical manifestations, the variable course of the disease, as well as the lack of proper diagnostic algorithms. Insufficiency of somatotropic axis is the most common abnormality, followed by presence of hypogonadism, hypothyroidism, hypocortisolism, and diabetes insipidus. The purpose of this review is to summarize the current state of knowledge about post-traumatic hypopituitarism. Moreover, based on available data and on our own clinical experience, we suggest an algorithm for the evaluation of post-traumatic hypopituitarism. In addition, well-designed studies are needed to further investigate the pathophysiology, epidemiology, and timing of pituitary dysfunction after a traumatic brain injury with the purpose of establishing appropriate standards of care.

Trauma and thyroid-stimulating hormone abnormalities in pediatric patients

Background

There is limited literature on trauma and endocrine abnormalities in the pediatric trauma setting.

Aim

We studied demographic, medical history, injury experience, and mortality factors to determine their association with abnormal thyroid-stimulating hormone in pediatric trauma patients.

Methods

The 414 pediatric trauma patients were from those seen at an emergency department. The primary outcome variable was abnormal thyroid-stimulating hormone. Secondary outcome variables were abnormal high and abnormal low thyroid-stimulating hormone. Predictor variables were demographics (age, sex, race/ethnicity, body mass index), medical history (thyroid disease, diabetes mellitus, autoimmune disease, psychiatric disease), injury experience (injury cause, injury severity score ≥ 15, moderate/severe traumatic brain injury, length of stay), and mortality (mortality, survival probability). Multivariate logistic regression analyses were conducted.

Results

There were 8.0% ( n = 33) with any abnormal thyroid-stimulating hormone value. In the analysis for abnormal thyroid-stimulating hormone, females (odds ratio:4.95, 95% confidence interval: 2.01, 12.21, p < 0.01) and traumatic brain injury (odds ratio: 8.11, 95% confidence interval: 2.51, 26.16, p < 0.001) were each significantly associated with increased odds. In the analysis for abnormal high thyroid-stimulating hormone (odds ratio: 3.75, 95% confidence interval: 1.37, 10.24, p < 0.05), traumatic brain injury (odds ratio: 11.59, 95% confidence interval: 3.45, 38.97, p < 0.001), and mortality (odds ratio: 35.59, 95% confidence interval: 1.40, 906.57, p < 0.05) were each significantly associated with increased odds. In the analysis for abnormal low thyroid-stimulating hormone, only females (odds ratio: 11.10, 95% confidence interval: 1.26, 97.60, p < 0.05) were significantly associated with increased odds.

Conclusion

In conclusion, females and traumatic brain injury have increased odds for abnormal thyroid-stimulating hormone. Mortality has increased odds for abnormal high thyroid-stimulating hormone. We suggest that clinicians in the pediatric trauma setting carefully monitor females and traumatic brain injury patients with abnormal thyroid-stimulating hormone.

Hypothalamic-Pituitary Disorders in Childhood Cancer Survivors: Prevalence, Risk Factors and Long-Term Health Outcomes

CONTEXT

Data on hypothalamic-pituitary (HP) disorders in systematically evaluated childhood cancer survivors are limited.

OBJECTIVE

To describe prevalence, risk factors, and associated adverse health outcomes of deficiencies in GH deficiency (GHD), TSH deficiency (TSHD), LH/FSH deficiency (LH/FSHD), and ACTH deficiency (ACTHD), and central precocious puberty (CPP).

DESIGN

Retrospective with cross-sectional health outcomes analysis.

SETTING

Established cohort; tertiary care center.

PATIENTS

Participants (N = 3141; median age, 31.7 years) were followed for a median 24.1 years.

MAIN OUTCOME MEASURE

Multivariable logistic regression was used to calculate ORs and 95% CIs for associations among HP disorders, tumor- and treatment-related risk factors, and health outcomes.

RESULTS

The estimated prevalence was 40.2% for GHD, 11.1% for TSHD, 10.6% for LH/FSHD, 3.2% for ACTHD, and 0.9% for CPP among participants treated with HP radiotherapy (n = 1089), and 6.2% for GHD, and <1% for other HP disorders without HP radiotherapy. Clinical factors independently associated with HP disorders included HP radiotherapy (at any dose for GHD, TSHD, LH/FSHD, >30 Gy for ACTHD), alkylating agents (GHD, LH/FSHD), intrathecal chemotherapy (GHD), hydrocephalus with shunt placement (GHD, LH/FSHD), seizures (TSHD, ACTHD), and stroke (GHD, TSHD, LH/FSHD, ACTHD). Adverse health outcomes independently associated with HP disorders included short stature (GHD, TSHD), severe bone mineral density deficit (GHD, LH/FSHD), obesity (LH/FSHD), frailty (GHD), impaired physical health-related quality of life (TSHD), sexual dysfunction (LH/FSHD), impaired memory, and processing speed (GHD, TSHD).

CONCLUSION

HP radiotherapy, central nervous system injury, and, to a lesser extent, chemotherapy are associated with HP disorders, which are associated with adverse health outcomes.

Silencing of A20 Aggravates Neuronal Death and Inflammation After Traumatic Brain Injury: A Potential Trigger of Necroptosis

Programmed cell death is an important biological process that plays an indispensable role in traumatic brain injury (TBI). Inhibition of necroptosis, a type of programmed cell death, is pivotal in neuroprotection and in preventing associated inflammatory responses. Our results showed that necroptosis occurred in human brain tissues after TBI. Necroptosis was also induced by controlled cortical impact (CCI) injury in a rat model of TBI and was accompanied by high translocation of high-mobility group box-1 (HMGB1) to the cytoplasm. HMGB1 was then passed through the impaired cell membrane to upregulate the receptor for advanced glycation end-products (RAGE), nuclear factor (NF)-κB, and inflammatory factors such as interleukin-6 (IL-6), interleukin-1 (IL-1β), as well as NACHT, LRR and PYD domains-containing protein 3 (NLRP3). Necroptosis was alleviated by necrostatin-1 and melatonin but not Z-VAD (a caspase inhibitor), which is consistent with the characteristic of caspase-independent signaling. This study also demonstrated that tumor necrosis factor, alpha-induced protein 3 (TNFAIP3, also known as A20) was indispensable for regulating and controlling necroptosis and inflammation after CCI. We found that a lack of A20 in a CCI model led to aggressive necroptosis and attenuated the anti-necroptotic effects of necrostatin-1 and melatonin.

Clinical characterization of men with long QT syndrome and torsades de pointes associated with hypogonadism: A review and pharmacovigilance study

BACKGROUND

Long QT syndrome (LQTS) can cause the potentially fatal ventricular tachycardia torsades de pointes (TdP). QT interval corrected for heart rate (QTc) is shorter in men than in women, with testosterone contributing to shorten QTc. We recently described male hypogonadism as a reversible risk factor for acquired LQTS and TdP, but the clinical characteristics of such patients have not been characterized.

AIMS

To describe the clinical characteristics of men with acquired LQTS or TdP associated with hypogonadism caused by endocrine conditions or androgen deprivation therapy (ADT), and to evaluate the relationship between testosterone concentrations and electrocardiographic changes.

METHODS

We searched MEDLINE (to 04 January 2019) and the French pharmacovigilance database (to 09 August 2018) to identify male cases of acquired LQTS and TdP associated with endocrine hypogonadism or ADT; their narratives were gathered from reporting collaborators.

RESULTS

We identified seven cases of TdP (one fatal) with endocrine hypogonadism, abnormally long QTc and morphologically abnormal T-wave notches. After reversion of low testosterone concentrations in the surviving patients (N=6), QTc shortened, T-wave morphology normalized and there was no TdP recurrence. Among these cases, none had mutation in the LQTS genes, three men required testosterone and three had reversible hypogonadism after resolution of a concurrent acute severe illness. We found an additional 27 reports of men with LQTS (N=6), TdP (N=9; 2/9 fatal) or sudden death (N=12; 10/12 fatal) suspected to be induced or favoured by ADT (24/27 for prostate cancer). Generally, after ADT withdrawal, QTc shortened and no TdP recurred.

CONCLUSION

We propose seeking for hypogonadism caused by endocrine conditions or ADT in men presenting with TdP. Caution is warranted when ADT is used in situations at risk of TdP. Testosterone may be useful to treat or prevent TdP.

Lateral fluid-percussion injury leads to pituitary atrophy in rats

Traumatic brain injury (TBI) causes neuroendocrine dysregulation in up to 40% of humans, which is related to impaired function of the hypothalamo-hypophyseal axis and contributes to TBI-related co-morbidities. Our objective was to investigate whether hypophyseal atrophy can be recapitulated in rat lateral fluid-percussion injury model of human TBI. High-resolution structural magnetic resonance images (MRI) were acquired from rats at 2 days and 5 months post-TBI. To measure the lobe-specific volumetric changes, manganese-enhanced MRI (MEMRI) scans were acquired from rats at 8 months post-TBI, which also underwent the pentylenetetrazol (PTZ) seizure susceptibility and Morris water-maze spatial memory tests. MRI revealed no differences in the total hypophyseal volume between TBI and controls at 2 days, 5 months or 8 months post-TBI. Surprisingly, MEMRI at 8 months post-TBI indicated a 17% reduction in neurohypophyseal volume in the TBI group as compared to controls (1.04 ± 0.05 mm3 vs 1.25 ± 0.05 mm3, p < 0.05). Moreover, neurohypophyseal volume inversely correlated with the number of PTZ-induced epileptiform discharges and the mean latency to platform in the Morris water-maze test. Our data demonstrate that TBI leads to neurohypophyseal lobe-specific atrophy and may serve as a prognostic biomarker for post-TBI outcome.

Risk of female sexual dysfunction following concussion in women of reproductive age

Objectives: Traumatic Brain Injury (TBI) has frequently been associated with changes in sexual functioning. The TBI and sexuality literature, however, has limited generalizability to concussed females, who often use the emergency department (ED) as their first line of care after head injury. Primary Objective: The primary objective of this study was to evaluate the impact of concussions on female sexual functioning. Secondary Objective: Secondarily, we evaluated if concussed women with sexual dysfunction also report more post-concussion symptoms (PCS) and/or mood changes. Research Design: This was a prospective cohort, with outcomes assessed at 6-10 weeks after ED enrollment. Methods and Procedures: Sexual dysfunction was defined as ≤ 45 on the Brain Injury Questionnaire on Sexuality (BIQS). The Rivermead Post-concussion Symptoms Questionnaire (RPQ) and the Hospital Anxiety and Depression Scale (HADS) assessed PCS and post-injury mood, respectively. Main Outcomes & Results: Eighty-nine eumenorrheic females (8-14 menstrual cycles/year) completed the study; 31(36%) had concussions, and 55(64%) were extremity injured. Concussed women had 70% increased risk of sexual dysfunction (adj.RR:1.70, 95% CI: 1.04,2.76; p = .03) versus extremity injured. Of clinical relevance, concussed women with sexual dysfunction also reported more PCS symptoms (adj.β = 5.5, 95% CI: -6.7,18.2; p = .37) and mood scores (adj.β = 8.0; 95% CI: -0.4, 16.4; p = .06). Conclusions: This study highlights the need for more research and interventions for one of the fastest growing subgroups within the TBI population.

Growth Hormone Deficiency Following Traumatic Brain Injury

Traumatic brain injury (TBI) is fairly common and annually affects millions of people worldwide. Post traumatic hypopituitarism (PTHP) has been increasingly recognized as an important and prevalent clinical entity. Growth hormone deficiency (GHD) is the most common pituitary hormone deficit in long-term survivors of TBI. The pathophysiology of GHD post TBI is thought to be multifactorial including primary and secondary mechanisms. An interplay of ischemia, cytotoxicity, and inflammation post TBI have been suggested, resulting in pituitary hormone deficits. Signs and symptoms of GHD can overlap with those of TBI and may delay rehabilitation/recovery if not recognized and treated. Screening for GHD is recommended in the chronic phase, at least six months to a year after TBI as GH may recover in those with GHD in the acute phase; conversely, it may manifest in those with a previously intact GH axis. Dynamic testing is the standard method to diagnose GHD in this population. GHD is associated with long-term poor medical outcomes. Treatment with recombinant human growth hormone (rhGH) seems to ameliorate some of these features. This review will discuss the frequency and pathophysiology of GHD post TBI, its clinical consequences, and the outcomes of treatment with GH replacement.

Brain Trauma Disrupts Hepatic Lipid Metabolism: Blame It on Fructose?

SCOPE

The action of brain disorders on peripheral metabolism is poorly understood. The impact of traumatic brain injury (TBI) on peripheral organ function and how TBI effects can be influenced by the metabolic perturbation elicited by fructose ingestion are studied.

METHODS AND RESULTS

It is found that TBI affects glucose metabolism and signaling proteins for insulin and growth hormone in the liver; these effects are exacerbated by fructose ingestion. Fructose, principally metabolized in the liver, potentiates the action of TBI on hepatic lipid droplet accumulation. Studies in isolated cultured hepatocytes identify GH and fructose as factors for the synthesis of lipids. The liver has a major role in the synthesis of lipids used for brain function and repair. TBI results in differentially expressed genes in the hypothalamus, primarily associated with lipid metabolism, providing cues to understand central control of peripheral alterations. Fructose-fed TBI animals have elevated levels of markers of inflammation, lipid peroxidation, and cell energy metabolism, suggesting the pro-inflammatory impact of TBI and fructose in the liver.

CONCLUSION

Results reveal the impact of TBI on systemic metabolism and the aggravating action of fructose. The hypothalamic-pituitary-growth axis seems to play a major role in the regulation of the peripheral TBI pathology.

Traumatic brain injury induced neuroendocrine changes: acute hormonal changes of anterior pituitary function

PURPOSE

It is estimated that approximately 69 million individuals worldwide will sustain a TBI each year, which accounts for substantial morbidity and mortality in both children and adults. TBI may lead to significant neuroendocrine changes, if the delicate pituitary is ruptured. In this review, we focus on the anterior pituitary hormonal changes in the acute post-TBI period and we present the evidence supporting the need for screening of anterior pituitary function in the early post-TBI time along with current suggestions regarding the endocrine assessment and management of these patients.

METHODS

Original systematic articles with prospective and/or retrospective design studies of acute TBI were included, as were review articles and case series.

RESULTS

Although TBI may motivate an acute increase of stress hormones, it may also generate a wide spectrum of anterior pituitary hormonal deficiencies. The frequency of post-traumatic anterior hypopituitarism (PTHP) varies according to the severity, the type of trauma, the time elapsed since injury, the study population, and the methodology used to diagnose pituitary hormone deficiency. Early neuroendocrine abnormalities may be transient, but additional late ones may also appear during the course of rehabilitation.

CONCLUSIONS

Acute hypocortisolism should be diagnosed and managed promptly, as it can be life-threatening, but currently there is no evidence to support treatment of acute GH, thyroid hormones or gonadotropins deficiencies. However, a more comprehensive assessment of anterior pituitary function should be undertaken both in the early and in the post-acute phase, since ongoing hormone deficiencies may adversely affect the recovery and quality of life of these patients.

A neurosurgical approach to traumatic brain injury and post-traumatic hypopituitarism

PURPOSE

Traumatic brain injury (TBI) is a common cause of mortality and major disability worldwide. The initial management often depends on the severity of the injury. Pituitary dysfunction can develop as a sequela of TBI, and can have long-term, debilitating impact on the patients. Early identification and prompt intervention of post-traumatic hypopituitarism (PTHP) is essential to prevent or minimize the adverse consequences of this condition. We hereby provide an overview of the current management of TBI from a neurosurgical standpoint. We then review the pathophysiology and risk factors of developing PTHP, as well as our recommendations for its management.

METHODS

A review of current literature on TBI and PTHP, including primary research articles, reviews and clinical guidelines.

RESULTS

The current neurosurgical approach to the management of TBI is presented, followed by the pathophysiology and risk factors of PTHP, as well as our recommendations for its management.

CONCLUSIONS

Post-traumatic hypopitutiarism is a serious and potentially debilitating condition that is likely under-recognised and under-diagnosed. From a neurosurgical perspective, we advocate a pragmatic approach, i.e. screening those considered at high risk of developing PTHP based on clinical features and biochemical/endocrinological testings; and referring them to a specialist endocrinologist for further management as indicated.

Traumatic brain injury and resultant pituitary dysfunction: insights from experimental animal models

PURPOSE

Traumatic brain injury (TBI) is a major worldwide cause of disability, often burdening young people with serious lifelong health problems. A frequent clinical complication is post-traumatic hypopituitarism (PTHP) manifesting in several hypothalamus-pituitary axes. The head trauma-induced mechanisms underlying PTHP remain largely unknown. Several hypotheses have been proposed including direct damage to the pituitary gland and hypothalamus, vascular events and autoimmunity. This review aims to provide a summary of the currently limited number of studies exploring hypothalamus-pituitary dysfunction in experimental animal TBI models.

RESULTS

Although the impact of different forms of TBI on a number of hypothalamus-pituitary axes has been investigated, consequences for pituitary tissue and function have only scarcely been described. Moreover, mechanisms underlying the endocrine dysfunctions remain under explored.

CONCLUSIONS

Studies on TBI-induced pituitary dysfunction are still scarce. More research is needed to acquire mechanistic insights into the pathophysiology of PTHP which may eventually open up the horizon toward better treatments, including pituitary-regenerative approaches.

The role of autoimmunity in pituitary dysfunction due to traumatic brain injury

PURPOSE

Traumatic brain injury (TBI) is one of the most common causes of mortality and long-term disability and it is associated with an increased prevalence of neuroendocrine dysfunctions. Post-traumatic hypopituitarism (PTHP) results in major physical, psychological and social consequences leading to impaired quality of life. PTHP can occur at any time after traumatic event, evolving through various ways and degrees of deficit, requiring appropriate screening for early detection and treatment. Although the PTHP pathophysiology remains to be elucitated, on the basis of proposed hypotheses it seems to be the result of combined pathological processes, with a possible role played by hypothalamic-pituitary autoimmunity (HPA). This review is aimed at focusing on this possible role in the development of PTHP and its potential clinical consequences, on the basis of the data so far appeared in the literature and of some results of personal studies on this issue.

METHODS

Scrutinizing the data so far appeared in literature on this topic, we have found only few studies evaluating the autoimmune pattern in affected patients, searching in particular for antipituitary and antihypothalamus autoantibodies (APA and AHA, respectively) by simple indirect immunofluorescence.

RESULTS

The presence of APA and/or AHA at high titers was associated with an increased risk of onset/persistence of PTHP.

CONCLUSIONS

HPA seems to contribute to TBI-induced pituitary damage and related PTHP. However, further prospective studies in a larger cohort of patients are needed to define etiopathogenic and diagnostic role of APA/AHA in development of post-traumatic hypothalamic/pituitary dysfunctions after a TBI.

A clinical and pathophysiological approach to traumatic brain injury-induced pituitary dysfunction

PURPOSE

This review aimed to evaluate the data underlying the pathophysiology of TBI-induced hypothalamo-pituitary dysfunction.

METHODS

Recent literature about the pathophysiology of TBI-induced hypothalamo-pituitary dysfunction reviewed.

RESULTS

Traumatic brain injury (TBI) is a worldwide epidemic that frequently leads to death; TBI survivors tend to sustain cognitive, behavioral, psychological, social, and physical disabilities in the long term. The most common causes of TBI include road accidents, falls, assaults, sports, work and war injuries. From an endocrinological perspective, TBIs are important, because they can cause pituitary dysfunction. Although TBI-induced pituitary dysfunction was first reported a century ago, most of the studies that evaluate this disorder were published after 2000. TBI due to sports and blast injury-related pituitary dysfunction is generally underreported, due to limited recognition of the cases.

CONCLUSION

The underlying pathophysiology responsible for post-TBI pituitary dysfunction is not clear. The main proposed mechanisms are vascular injury, direct traumatic injury to the pituitary gland, genetic susceptibility, autoimmunity, and transient medication effects.

Pituitary pathology in traumatic brain injury: a review

PURPOSE

Traumatic brain injury most commonly affects young adults under the age of 35 and frequently results in reduced quality of life, disability, and death. In long-term survivors, hypopituitarism is a common complication.

RESULTS

Pituitary dysfunction occurs in approximately 20-40% of patients diagnosed with moderate and severe traumatic brain injury giving rise to growth hormone deficiency, hypogonadism, hypothyroidism, hypocortisolism, and central diabetes insipidus. Varying degrees of hypopituitarism have been identified in patients during both the acute and chronic phase. Anterior pituitary hormone deficiency has been shown to cause morbidity and increase mortality in TBI patients, already encumbered by other complications. Hypopituitarism after childhood traumatic brain injury may cause treatable morbidity in those survivors. Prospective studies indicate that the incidence rate of hypopituitarism may be ten-fold higher than assumed; factors altering reports include case definition, geographic location, variable hospital coding, and lost notes. While the precise pathophysiology of post traumatic hypopituitarism has not yet been elucidated, it has been hypothesized that, apart from the primary mechanical event, secondary insults such as hypotension, hypoxia, increased intracranial pressure, as well as changes in cerebral flow and metabolism may contribute to hypothalamic-pituitary damage. A number of mechanisms have been proposed to clarify the causes of primary mechanical events giving rise to ischemic adenohypophysial infarction and the ensuing development of hypopituitarism.

CONCLUSION

Future research should focus more on experimental and clinical studies to elucidate the exact mechanisms behind post-traumatic pituitary damage. The use of preventive medical measures to limit possible damage in the pituitary gland and hypothalamic pituitary axis in order to maintain or re-establish near normal physiologic functions are crucial to minimize the effects of TBI.

Hypopituitarism post traumatic brain injury (TBI): review

Post-traumatic hypopituitarism (PTHP) is an important and relatively common complication of TBI (traumatic brain injury). A number of studies have shown that this clinical phenomenon can occur soon after TBI (acute) or later in the chronic phase. Patients with moderate to severe TBI are at a particular risk of developing PTHP. In the acute setting, it is important to monitor patients for hypoadrenalism as this confers a high risk for morbidity and even mortality. The gonadotrophin, growth hormone and TSH deficiencies are better defined in the chronic phase. Untreated PTHP can lead to delayed recovery, impaired rehabilitation and persistent neuropsychiatric symptoms. This review will discuss the frequency and natural history of PTHP and its clinical implications and propose a pathway for investigation and management of this still under-recognised entity.

Hypopituitarism After Traumatic Brain Injury

Acquired hypopituitarism is associated with traumatic brain injury. This neuroendocrine dysfunction can cause both short-term and long-term morbidity resulting in a cognitive, physiological, and behavioral decline, which increases the burden of the disease and the cost of care. Data in the trauma literature is derisory on this subject. The aim of this review is to edify clinicians on this condition, outline the screening criteria and methods for hypopituitarism after traumatic brain injury, and bring awareness to the chronic effects.

Sex Differences in Sex Hormone Profiles and Prediction of Consciousness Recovery After Severe Traumatic Brain Injury

Objective: The clinical course of unconsciousness after traumatic brain injury (TBI) is commonly unpredictable and it remains a challenge with limited therapeutic options. The aim of this study was to evaluate the early changes in serum sex hormone levels after severe TBI (sTBI) and the use of these hormones to predict recovery from unconsciousness with regard to sex. Methods: We performed a retrospective study including patients with sTBI. A statistical of analysis of serum sex hormone levels and recovery of consciousness at 6 months was made to identify the effective prognostic indicators. Results: Fifty-five male patients gained recovery of consciousness, and 37 did not. Of the female patients, 22 out of 32 patients regained consciousness. Male patients (n = 92) with sTBI, compared with healthy subjects (n = 60), had significantly lower levels of follicular stimulating hormone (FSH), testosterone and progesterone and higher levels of prolactin. Female patients (n = 32) with sTBI, compared with controls (n = 60), had significantly lower levels of estradiol, progesterone, and testosterone and significantly higher levels of FSH and prolactin. Testosterone significantly predicted consciousness recovery in male patients. Normal or elevated testosterone levels in the serum were associated with a reduced risk of the unconscious state in male patients with sTBI. For women patients with sTBI, sex hormone levels did not contribute to the prediction of consciousness recovery. Conclusion: These findings indicate that TBI differentially affects the levels of sex-steroid hormones in men and women patients. Plasma levels of testosterone could be a good candidate blood marker to predict recovery from unconsciousness after sTBI for male patients.

High frequency of empty sella, with gender differences, in the early neuroradiology evaluation of patients with traumatic brain injury. A prospective study

One-hundred four persons aged ≥ 18 years (62 males and 42 females) who were admitted for traumatic brain injury (TBI) underwent brain computed tomography (CT) scan and assay of serum cortisol, insulin-like growth factor 1 (IGF-1), thyrotropin (TSH) and free thyroxine (FT4). The main purpose was to assess any gender difference and the rate of empty sella (ES).

Women were more likely to have empty sella (19/42 [45.2%] vs 19/62 [30.6%], P = 0.15, OR = 1.9), which was more frequently total ES or TES (16/19 [84.2%] vs 3/19 [15.8%], P = 0.0025, OR = 11.6). Neuroradiology was normal in the remaining 65 patients. Patients with TES were approximately 20–30 years older than both patients with partial ES (PES) and normal sella, but only the comparison with normal sella was significant (P = 0.001 all patients, P = 0.005 males). Presumed deficiency of IGF-1, cortisol or TSH occurred in 33 persons (31.7%; 20 Males [32.2%], 13 Females [30.9%]), 14 (13.5%; 10 M [16.2%], 4F [9.5%]) or 8 (7.7%; 1 M [1.7%], 7F [16.7%]), with only TSH deficiency having significant intergender difference (P = 0.007). The highest or lowest rates of IGF-1 deficiency occurred in men with PES (41.7%) or men with TES (14.3%), of cortisol deficiency in men with PES (33.3%) or women with PES (zero), and TSH deficiency in women with TES (18.7%) or both men and women with PES (zero) and men with normal sella (zero). Within ES, males with no deficiency were older compared to males with at least one hormone deficiency (75.7 ± 17.4 vs 55.6 ± 18.9, P = 0.022); in turn, the former males were also older compared with normal sella males having no hormone deficiency (54.1 ± 25.2, P = 0.023).

In conclusion, ES is detectable in almost 40% of persons who undergo CT within 24 h from TBI. A number of intergender differences concerning ES and the hormones evaluated are apparent.

Pituitary dysfunction and association with fatigue in stroke and other acute brain injury

BACKGROUND

Poststroke fatigue (PSF) is a highly prevalent and debilitating condition. However, the etiology remains incompletely understood. Literature suggests the co-prevalence of pituitary dysfunction (PD) with stroke, and the question raises whether this could be a contributing factor to the development of PSF. This study reviews the prevalence of PD after stroke and other acquired brain injuries and its association with fatigue.

SUMMARY

We performed a bibliographic literature search of MEDLINE and EMBASE databases for English language studies on PD in adult patients with stroke, traumatic brain injury (TBI) or aneurysmatic subarachnoid hemorrhage (aSAH). Forty-two articles were selected for review. Up to 82% of patients were found to have any degree of PD after stroke. Growth hormone deficiency was most commonly found. In aSAH and TBI, prevalences up to 49.3% were reported. However, data differed widely between studies, mostly due to methodological differences including the diagnostic methods used to define PD and the focus on the acute or chronic phase. Data on PD and outcome after stroke, aSAH and TBI are conflicting. No studies were found investigating the association between PD and PSF. Data on the association between PD and fatigue after aSAH and TBI were scarce and conflicting, and fatigue is rarely been investigated as a primary end point.

KEY MESSAGES

Data according to the prevalence of PD after stroke and other acquired brain injury suggest a high prevalence of PD after these conditions. However, the clinical relevance and especially the association with fatigue need to be established.

Cortisol evaluation during the acute phase of traumatic brain injury-A prospective study

BACKGROUND

Biochemical diagnosis of adrenal insufficiency (AI) is difficult in the context of traumatic brain injury (TBI).

AIM

To assess the frequency and predictive factors of AI in victims of TBI from Algiers.

METHODS

Between November 2009 and December 2013, TBI victims had a single 8-9 am serum cortisol measurement during the acute postinjury period (0-7 days). AI was defined according to basal cortisol levels of 83, 276 and 414 nmol/L. Variables studied were TBI severity according to Glasgow coma scale, duration of intubation and coma, pupillary status, hypotension, anaemia, brain imaging findings, diabetes insipidus and medication. Insulin tolerance test was performed during the recovery phase, defining AI as peak cortisol <500 nmol/L.

RESULTS

Cortisol samples were obtained at median 3 (1-7) days from 277 patients (257M: 20F) aged 32 (18-65) years. Acute AI frequency was 8 (2.8%), 20 (21%) and 35 (37%), respectively using the three cortisol cut-offs. Factors predicting AI were diastolic hypotension, sedative medication, diabetes insipidus, skull base fracture and intraparenchymal haematoma. Mortality was highest in patients with acute cortisol <276 nmol/L (44.6% with OR for death 1.64, 95% CI 0.92-3.0, P = .12). During the recovery phase, AI was present in 3 of 3, 12 of 24, 4 of 16 and 20 of 66 patients with week 1 cortisol <83, 83-276, 277-414 and >414 nmol/L.

CONCLUSION

Hydrocortisone replacement is advised in TBI patients with morning cortisol <276 nmol/L or those <414 nmol/L with additional risk factors for AI. As acute and subsequent AI are poorly correlated, patients with moderate/severe TBI require adrenal re-evaluation during the recovery phase.

Neuroendocrine Abnormalities Following Traumatic Brain Injury: An Important Contributor to Neuropsychiatric Sequelae

Neuropsychiatric symptoms following traumatic brain injury (TBI) are common and contribute negatively to TBI outcomes by reducing overall quality of life. The development of neurobehavioral sequelae, such as concentration deficits, depression, anxiety, fatigue, and loss of emotional well-being has historically been attributed to an ambiguous "post-concussive syndrome," considered secondary to frank structural injury and axonal damage. However, recent research suggests that neuroendocrine dysfunction, specifically hypopituitarism, plays an important role in the etiology of these symptoms. This post-head trauma hypopituitarism (PHTH) has been shown in the past two decades to be a clinically prevalent phenomenon, and given the parallels between neuropsychiatric symptoms associated with non-TBI-induced hypopituitarism and those following TBI, it is now acknowledged that PHTH is likely a substantial contributor to these impairments. The current paper seeks to provide an overview of hypothesized pathophysiological mechanisms underlying neuroendocrine abnormalities after TBI, and to emphasize the significance of this phenomenon in the development of the neurobehavioral problems frequently seen after head trauma.