Chronic trauma in sports as a cause of hypopituitarism

Evaluation of pituitary function and metabolic parameters in patients with traumatic maxillofacial fractures

PURPOSE

This study was designed to assess the pituitary functions of patients with traumatic maxillofacial fractures and compare the results with healthy controls.

METHODS

Thirty patients (mean age, 38.14 ± 14.15 years; twenty-six male, four female) with a traumatic maxillofacial fracture at least 12 months ago (mean 27.5 ± 6.5 months) and thirty healthy controls (mean age, 42.77 ± 11.36 years; twenty-five male, five female) were included. None of the patients were unconscious following head trauma, and none required hospitalization in intensive care. Basal pituitary hormone levels of the patients were evaluated. All patients and controls had a glucagon stimulation test and an ACTH stimulation test to evaluate the hypothalamic-pituitary-adrenal axis and the GH-IGF-1 axis.

RESULTS

Five of thirty patients (16.6%) had isolated growth hormone (GH) deficiency based on a glucagon stimulation test (GST). The mean peak GH level after GST in patients with hypopituitarism (0.54 ng/ml) was significantly lower than those without hypopituitarism (7.01 ng/ml) and healthy controls (11.70 ng/ml) (P < 0.001). No anterior pituitary hormone deficiency was found in the patients, except for GH.

CONCLUSION

Our study is the first to evaluate the presence of hypopituitarism in patients with traumatic maxillofacial fractures. Preliminary findings suggest that hypopituitarism and GH deficiency pose significant risks to these patients, particularly during the chronic phase of their trauma. However, these findings need to be validated in larger scale prospective studies with more patients.

It's in the game: A review of neurological lesions associated with sports

INTRODUCTION

The practice of sports may lead to neurological injuries. While relatively uncommon (overall incidence of approximately 2.5%), and mostly benign and transient, some conditions may be life-threatening and permanent. Thus, both clinical neurologists and sports physicians should be aware of their existence and relevance. We aimed to review all sports-related neurological injuries and illnesses reported in the literature.

METHODS

Following SANRA guidelines, we performed a narrative review and searched PubMed and Scopus databases. Relevant sports were selected based on their recognition as an Olympic sport by the International Olympic Committee. Chronic traumatic encephalopathy (CTE) and other neurodegenerative disorders were not included.

RESULTS

A total of 292 studies were included concerning 33 different sports. The most reported neurological injury was damage to the peripheral nervous system. Traumatic injuries have also been extensively reported, including cerebral haemorrhage and arterial dissections. Non-traumatic life-threatening events are infrequent but may also occur, e.g. posterior reversible encephalopathy syndrome, cerebral venous thrombosis, and arterial dissections. Some conditions were predominantly reported in specific sports, e.g. yips in baseball and golf, raising the possibility of a common pathophysiology. Spinal cord infarction due to fibrocartilaginous embolism was reported in several sports associated with minor trauma.

CONCLUSION

Sports-related neurological injuries are increasingly receiving more social and medical attention and are an important cause of morbidity and mortality. This review may serve as a guide to physicians managing these challenging situations.

INVESTIGATION OF PITUITARY DYSFUNCTION IN RETIRED PROFESSIONAL SOCCER PLAYERS

ABSTRACT Introduction: It is well-known that pituitary dysfunction can develop as a result of traumatic brain injuries. One reason for such injuries is collision during contact sports. Objectives: The aim of this study was to investigate the effects of heading the ball and concussion on pituitary function in retired soccer players. Methods: Thirty-two retired soccer players, with an average age of 43.38 ± 5.49 (35-59) and 26 sedentary individuals with an average age of 43.31±6.38 (35-59) were included in this study. The subjects were questioned about their soccer-playing background, history of head trauma and concussion, and cardiometabolic diseases. One day one, blood samples were taken to investigate the baseline hematologic and biochemical parameters. On day two, the ACTH stimulation test was conducted, and on day three, glucagon stimulation tests were carried out. Resting EKG, transthoracic ECHO and exercise stress tests (for MET values) were also conducted. For the statistical analysis, The Student's t-test was used to compare the results of the two groups. The level of significance adopted was p<0.05. Results: It was identified that 5 out of 32 soccer players (16%) had experienced concussion during their soccer careers. The growth hormone (GH) levels of 3 retired soccer players (9.2%) and 3 sedentary individuals (10%) was below 1 ng/dl, which was accepted as the threshold value. There were no significant differences between hematological, biochemical and cardiometabolic parameters of the soccer players with low GH levels and those with normal GH levels. There was no significant relationship between the number of headers performed and GH deficiency. Conclusion: Although low GH levels were detected in almost 10% of the retired soccer players, the frequency of hypopituitarism was not higher than in the sedentary control group. Level of evidence I; Prognostic Studies.

Impact of Pituitary Autoimmunity and Genetic Disorders on Growth Hormone Deficiency in Children and Adults

Growth hormone (GH), mostly through its peripheral mediator, the insulin-like growth factor 1(IGF1), in addition to carrying out its fundamental action to promote linear bone growth, plays an important role throughout life in the regulation of intermediate metabolism, trophism and function of various organs, especially the cardiovascular, muscular and skeletal systems. Therefore, if a prepubertal GH secretory deficiency (GHD) is responsible for short stature, then a deficiency in adulthood identifies a nosographic picture classified as adult GHD syndrome, which is characterized by heart, muscle, bone, metabolic and psychic abnormalities. A GHD may occur in patients with pituitary autoimmunity; moreover, GHD may also be one of the features of some genetic syndromes in association with other neurological, somatic and immune alterations. This review will discuss the impact of pituitary autoimmunity on GHD and the occurrence of GHD in the context of some genetic disorders. Moreover, we will discuss some genetic alterations that cause GH and IGF-1 insensitivity and the arguments in favor and against the influence of GH/IGF-1 on longevity and cancer in the light of the papers on these issues that so far appear in the literature.

Peripheral blood neuroendocrine hormones are associated with clinical indices of sport-related concussion

The purpose of this study was to evaluate the relationship between neuroendocrine hormones and clinical recovery following sport-related concussion (SRC). Ninety-five athletes (n = 56 male, n = 39 female) from a cohort of 11 interuniversity sport teams at a single institution provided blood samples; twenty six athletes with SRC were recruited 2–7 days post-injury, and 69 uninjured athletes recruited prior to the start of their competitive season. Concentrations of seven neuroendocrine hormones were quantitated in either plasma or serum by solid-phase chemiluminescent immunoassay. The Sport Concussion Assessment Tool version 5 (SCAT-5) was used to evaluate symptoms at the time of blood sampling in all athletes. Multivariate partial least squares (PLS) analyses were used to evaluate the relationship between blood hormone concentrations and both (1) time to physician medical clearance and (2) initial symptom burden. A negative relationship was observed between time to medical clearance and both dehydroepiandrosterone sulfate (DHEA-S) and progesterone; a positive relationship was found between time to medical clearance and prolactin. Cognitive, somatic, fatigue and emotion symptom clusters were associated with distinct neuroendocrine signatures. Perturbations to the neuroendocrine system in athletes following SRC may contribute to initial symptom burden and longer recovery times.

The history of pituitary dysfunction after traumatic brain injury

PURPOSE

To estimate the total number of articles on traumatic brain injury (TBI)-related hypopituitarism and patients (including children and adolescents) with such disorder that were published until now, particularly after the author's review published on April 2000.

METHODS

Review of the literature retrievable on PubMed.

RESULTS

TBI-related hypopituitarism accounts for 7.2% of the whole literature on hypopituitarism published during the 18 years and half between May 2000 and October 2018. As a result, the total number of patients with TBI-related hypopituitarism now approximates 2200. A number of patients, both adults and children, continue to be published as case reports. Articles, including reviews and guidelines, have been published in national languages in order to maximize locally the information on TBI-related hypopituitarism. TBI-related hypopituitarism has been also studied in animals (rodents, cats and dogs).

CONCLUSIONS

The interest for the damage suffered by anterior pituitary as a result of TBI continues to remain high both in the adulthood and childhood.

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.

Sports-Related Repetitive Traumatic Brain Injury: A Novel Cause of Pituitary Dysfunction

Traumatic brain injury (TBI) is one of the major causes of disability and death, particularly in the young population. Recent clinical studies have demonstrated that TBI-induced pituitary dysfunction occurs more frequently than previously estimated, and this may contribute to delayed diagnosis and treatment of hormonal abnormalities. Today, the popularity of combative sports increases, and athletes who deal with these sports have risks of developing hypopituitarism attributed to repetitive TBIs. Pathogenesis and molecular mechanisms are not completely understood yet. Current studies suggest that athletes who had retired, especially from combative sports, should be screened for hypopituitarism. In this review, we aim to increase the awareness of medical communities, athletes, coaches, and athletic trainers about this issue by sharing the current studies regarding the pituitary dysfunction attributed to repetitive TBI associated with sports.

Neuroendocrine Dysfunction in a Young Athlete With Concussion: A Case Report

An 18-year-old female ringette and basketball player presented to our sport concussion clinic 27 months after concussion with fatigue, headache, exercise intolerance, polyuria, nocturia, and difficulties concentrating. Her history was remarkable for 4 previous concussions. Her neurologic examination was normal. Neuroendocrine screen including thyroid function, morning cortisol, glucose, and insulin-like growth factor-1 (screening test for growth hormone deficiency) were normal. Further testing for growth hormone deficiency with an insulin hypoglycemia test revealed severe growth hormone deficiency. Urine and serum electrolytes were borderline normal, suggesting partial diabetes insipidus. Treatments with growth hormone replacement lead to complete recovery. This case highlights the importance of maintaining a high index of suspicion for neuroendocrine abnormalities in athletes with persistent symptoms after sport concussion. Symptoms can be nonspecific and go undiagnosed for years, but appropriate recognition and treatment can restore function.

Growth hormone deficiency and hypopituitarism in adults after complicated mild traumatic brain injury

PURPOSE

Traumatic brain injury is considered the main cause of hypopituitarism in adults, and GH deficiency appears to be the most frequent pituitary deficit. Most of the available studies have included all degrees of severity of trauma. We aimed to assess pituitary function and GH deficiency in adult patients at different time lengths after complicated mild TBI according to Glasgow Coma Scale. We also aimed to evaluate whether mild TBI patients with GH deficiency had developed alterations in the glycolipid profile.

METHODS

Forty-eight patients (34 men and 14 women) with complicated mild TBI were included in the study. Twenty-three patients were evaluated at 1 year (Group A) and 25 patients at 5 years or longer after the injury (Group B). All patients underwent basal hormonal evaluation for pituitary function. GH deficiency was investigated by the combined test (GH releasing hormone + arginine). The glycolipid profile was also evaluated.

RESULTS

GH deficiency occurred in 8/23 patients (34.7 %) of Group A and in 12/25 patients (48 %) of Group B. In addition, two patients, one in each group, showed evidence of central hypothyroidism. Patients with GH deficiency, especially in Group A, presented a higher frequency of visceral adiposity and adverse metabolic profile as compared to no-GH deficiency patients.

CONCLUSIONS

Patients examined at 1 year or several years from complicated mild TBI had a similarly high occurrence of isolated GH deficiency, which was associated with visceral adiposity and metabolic alterations. Our findings suggest that patients undergone complicated mild TBI should be evaluated for GH deficiency even after several years from trauma.

Classical and non-classical causes of GH deficiency in adults

Growth hormone deficiency (GHD) can develop due to a variety of conditions, and may occur either as isolated or multiple pituitary hormone deficiencies. It has been previously demonstrated that GH is one of the most frequent hormonal deficiencies in adult patients with hypopituitarism. The most frequent classical causes of adult-onset GHD (AO-GHD) are pituitary adenomas and/or their treatment. However, during the last decade an increasing number of studies from different parts of the world have revealed that non-tumoural causes of hypopituitarism are more common than previously known. Therefore, in this review our aim is to briefly summarize the classical and non-classical acquired causes of GHD in adults.

GH and Pituitary Hormone Alterations After Traumatic Brain Injury

Traumatic brain injury (TBI) is a crucially important public health problem around the world, which gives rise to increased mortality and is the leading cause of physical and psychological disability in young adults, in particular. Pituitary dysfunction due to TBI was first described 95 years ago. However, until recently, only a few papers have been published in the literature and for this reason, TBI-induced hypopituitarism has been neglected for a long time. Recent studies have revealed that TBI is one of the leading causes of hypopituitarism. TBI which causes hypopituitarism may be characterized by a single head injury such as from a traffic accident or by chronic repetitive head trauma as seen in combative sports including boxing, kickboxing, and football. Vascular damage, hypoxic insult, direct trauma, genetic predisposition, autoimmunity, and neuroinflammatory changes may have a role in the development of hypopituitarism after TBI. Because of the exceptional structure of the hypothalamo-pituitary vasculature and the special anatomic location of anterior pituitary cells, GH is the most commonly lost hormone after TBI, and the frequency of isolated GHD is considerably high. TBI-induced pituitary dysfunction remains undiagnosed and therefore untreated in most patients because of the nonspecific and subtle clinical manifestations of hypopituitarism. Treatment of TBI-induced hypopituitarism depends on the deficient anterior pituitary hormones. GH replacement therapy has some beneficial effects on metabolic parameters and neurocognitive dysfunction. Patients with TBI without neuroendocrine changes and those with TBI-induced hypopituitarism share the same clinical manifestations, such as attention deficits, impulsion impairment, depression, sleep abnormalities, and cognitive disorders. For this reason, TBI-induced hypopituitarism may be neglected in TBI victims and it would be expected that underlying hypopituitarism would aggravate the clinical picture of TBI itself. Therefore, the diagnosis and treatment of unrecognized hypopituitarism due to TBI are very important not only to decrease morbidity and mortality due to hypopituitarism but also to alleviate the chronic sequelae caused by TBI.

Pituitary cell differentiation from stem cells and other cells: toward restorative therapy for hypopituitarism?

The pituitary gland, key regulator of our endocrine system, produces multiple hormones that steer essential physiological processes. Hence, deficient pituitary function (hypopituitarism) leads to severe disorders. Hypopituitarism can be caused by defective embryonic development, or by damage through tumor growth/resection and traumatic brain injury. Lifelong hormone replacement is needed but associated with significant side effects. It would be more desirable to restore pituitary tissue and function. Recently, we showed that the adult (mouse) pituitary holds regenerative capacity in which local stem cells are involved. Repair of deficient pituitary may therefore be achieved by activating these resident stem cells. Alternatively, pituitary dysfunction may be mended by cell (replacement) therapy. The hormonal cells to be transplanted could be obtained by (trans-)differentiating various kinds of stem cells or other cells. Here, we summarize the studies on pituitary cell regeneration and on (trans-)differentiation toward hormonal cells, and speculate on restorative therapies for pituitary deficiency.

Emerging pharmacotherapy for treatment of traumatic brain injury: targeting hypopituitarism and inflammation

INTRODUCTION

Traumatic brain injury (TBI) is a common cause of morbidity and mortality in the developed world. In particular, TBI is an important cause of death and disability in young adults with consequences ranging from physical disabilities to long-term cognitive, behavioural, psychological and social defects.

AREAS COVERED

There is a large body of evidence that suggest that TBI conditions may adversely affect pituitary function in both the acute and chronic phases of recovery. Prevalence of hypopituitarism, from total to isolated pituitary deficiency, ranges from 5 to 90%. The time interval between TBI and pituitary function evaluation is one of the major factors responsible for variations in the prevalence of hypopituitarism reported. Diagnosis of hypopituitarism and accurate treatment of pituitary disorders offers the opportunity to improve mortality and outcome in TBI conditions.

EXPERT OPINION

The aim of this paper is to review the history and pathophysiology of TBI and to summarize the best evidence of TBI as a cause of pituitary deficiency. Moreover, in this article we will describe the multiple changes which occur within the hypothalamic-pituitary-thyroid axis in critical illness, giving rise to 'sick euthyroid syndrome', focus our attention on thyroid hormones circulating levels from the initial insult to critical illness.

Pituitary dysfunction after traumatic brain injury: a clinical and pathophysiological approach

Traumatic brain injury (TBI) is a growing public health problem worldwide and is a leading cause of death and disability. The causes of TBI include motor vehicle accidents, which are the most common cause, falls, acts of violence, sports-related head traumas, and war accidents including blast-related brain injuries. Recently, pituitary dysfunction has also been described in boxers and kickboxers. Neuroendocrine dysfunction due to TBI was described for the first time in 1918. Only case reports and small case series were reported until 2000, but since then pituitary function in TBI victims has been investigated in more detail. The frequency of hypopituitarism after TBI varies widely among different studies (15-50% of the patients with TBI in most studies). The estimates of persistent hypopituitarism decrease to 12% if repeated testing is applied. GH is the most common hormone lost after TBI, followed by ACTH, gonadotropins (FSH and LH), and TSH. The underlying mechanisms responsible for pituitary dysfunction after TBI are not entirely clear; however, recent studies have shown that genetic predisposition and autoimmunity may have a role. Hypopituitarism after TBI may have a negative impact on the pace or degree of functional recovery and cognition. What is not clear is whether treatment of hypopituitarism has a beneficial effect on specific function. In this review, the current data related to anterior pituitary dysfunction after TBI in adult patients are updated, and guidelines for the diagnosis, follow-up strategies, and therapeutic approaches are reported.

Neuroendocrine Disturbances after Brain Damage: An Important and Often Undiagnosed Disorder

Traumatic brain injury (TBI) is a common and significant public health problem all over the world. Until recently, TBI has been recognized as an uncommon cause of hypopituitarism. The studies conducted during the last 15 years revealed that TBI is a serious cause of hypopituitarism. Although the underlying pathophysiology has not yet been fully clarified, new data indicate that genetic predisposition, autoimmunity and neuroinflammatory changes may play a role in the development of hypopituitarism. Combative sports, including boxing and kickboxing, both of which are characterized by chronic repetitive head trauma, have been shown as new causes of neuroendocrine abnormalities, mainly hypopituitarism, for the first time during the last 10 years. Most patients with TBI-induced pituitary dysfunction remain undiagnosed and untreated because of the non-specific and subtle clinical manifestations of hypopituitarism. Replacement of the deficient hormones, of which GH is the commonest hormone lost, may not only reverse the clinical manifestations and neurocognitive dysfunction, but may also help posttraumatic disabled patients resistant to classical treatment who have undiagnosed hypopituitarism and GH deficiency in particular. Therefore, early diagnosis, which depends on the awareness of TBI as a cause of neuroendocrine abnormalities among the medical community, is crucially important.

Pituitary dysfunction following traumatic brain injury: clinical perspectives

Traumatic brain injury (TBI) is a well recognized public health problem worldwide. TBI has previously been considered as a rare cause of hypopituitarism, but an increased prevalence of neuroendocrine dysfunction in patients with TBI has been reported during the last 15 years in most of the retrospective and prospective studies. Based on data in the current literature, approximately 15%-20% of TBI patients develop chronic hypopituitarism, which clearly suggests that TBI-induced hypopituitarism is frequent in contrast with previous assumptions. This review summarizes the current data on TBI-induced hypopituitarism and briefly discusses some clinical perspectives on post-traumatic anterior pituitary hormone deficiency.

Evaluation of long-term pituitary functions in patients with severe ventricular arrhythmia: a pilot study

INTRODUCTION

Traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), stroke and cerebrovascular disease (CVD) are identified as risk factors for hypopituitarism. Pituitary dysfunction after TBI, SAH, and CVD may present in the acute phase or later in the course of the event. Chronic hypopituitarism, particularly growth hormone (GH) deficiency is related to the increased cardiovascular morbidity and mortality. In patients with serious ventricular arrhythmias, who need cardiopulmonary resuscitation, brain tissue is exposed to short-term severe ischemia and hypoxia. However, there are no data in the literature regarding pituitary dysfunction after ventricular arrhythmias.

PATIENTS AND METHODS

Forty-four patients with ventricular arrhythmias [ventricular tachycardia (VT), ventricular fibrillation (VF)] (mean age, 55.6 ± 1.8 years; 37 men, 7 women) were included in the study. The patients were evaluated after mean period of 21.2 ± 0.8 months from VT-VF. Basal hormone levels, including serum free triiodothyronine (fT3), free thyroxine (fT4), TSH, ACTH, prolactin, FSH, LH, total testosterone, estradiol, IGF-1, and cortisol levels were measured in all patients. To assess (GH)-insulin like growth factor-1 (IGF-1) axis, glucagon stimulation test was performed and 1 µg ACTH stimulation test was used for assessing hypothalamic-pituitary-adrenal (HPA) axis.

RESULTS

The frequencies of GH, gonadotropin and TSH deficiency were 27.2, 9.0, 2.2%, respectively. Mean IGF-1 levels were lower in GH deficiency group, but it was not statistically significant.

CONCLUSION

The present preliminary study showed that ventricular arrhythmias may result in hypopituitarism, particularly in growth hormone deficiency. Unrecognized hypopituitarism may be responsible for some of the cardiovascular problems at least in some patients.

Pituitary function in subjects with mild traumatic brain injury: a review of literature and proposal of a screening strategy

Traumatic brain injury (TBI) is an important public health problem all over the world. The level of consciousness of the patients and the severity of the brain injury is commonly evaluated by the Glascow Coma Scale as mild, moderate and severe TBI. When we consider the high frequency of mild TBI (MTBI) among the all TBI patients the burden of the pituitary dysfunction problem in this group could not be ignored. However, one of the most important and still unresolved questions is which patients with MTBI should be screened for hypopituitarism? Another type of head trauma which could be considered as the subgroup of MTBI is sports related chronic repetitive head trauma. Therefore, in this review we will discuss the frequency, characteristics and current management of pituitary dysfunction in patients with MTBI including the subjects exposed to sports related chronic mild head trauma.

Apolipoprotein E3/E3 genotype decreases the risk of pituitary dysfunction after traumatic brain injury due to various causes: preliminary data

Traumatic brain injury (TBI) is a devastating public health problem which may result in hypopituitarism. However, the mechanisms and the risk factors responsible for hypothalamo-pituitary dysfunction due to TBI are still unclear. Although APO E is one of the most abundant protein in hypothalamo-pituitary region, there is no study investigating the relation between APO E polymorphism and TBI-induced hypopituitarism. This study was undertaken to determine whether APO E genotypes modulate the pituitary dysfunction risk after TBI due to various causes, including traffic accident, boxing, and kickboxing. Ninety-three patients with TBI (mean age, 30.61 +/- 1.25 years) and 27 healthy controls (mean age, 29.03 +/- 1.70 years) were included in the study. Pituitary functions were evaluated, and APO E genotypes (E2/E2; E3/E3; E4/E4; E2/E3; E2/E4; E3/E4) were screened. Twenty-four of 93 subjects (25.8%) had pituitary dysfunction after TBI. The ratio of pituitary dysfunction was significantly lower in subjects with APO E3/E3 (17.7%) than the subjects without APO E3/E3 genotype (41.9%; p = 0.01), and the corresponding odds ratio was 0.29 (95% confidence interval [CI], 0.11-0.78). In conclusion, this study provides strong evidence for the first time that APO E polymorphism is associated with the development of TBI-induced pituitary dysfunction. Present data demonstrated that APO E3/E3 genotype decreases the risk of hypopituitarism after TBI. The demonstration of the association between the APO E polymorphism and TBI may provide a new point of view in this field and promote further studies.

Antipituitary antibodies after traumatic brain injury: is head trauma-induced pituitary dysfunction associated with autoimmunity?

OBJECTIVE

Traumatic brain injury (TBI) is a devastating public health problem that may result in hypopituitarism. However, the mechanisms responsible for hypothalamic-pituitary dysfunction due to TBI are still unclear. Although the antibodies against neurons have been demonstrated in injured animal studies, investigations regarding the occurrence of antipituitary antibodies (APAs) in patients with TBI are lacking in the literature. In order to investigate whether autoimmune mechanisms could play a role in the pituitary dysfunction after TBI, we have planned this study aimed at investigating the presence of APA at the third year of TBI and association between the TBI-induced hypopituitarism and APA.

PATIENTS AND DESIGN

Twenty-nine (25 males and 4 females; age 36.5+/-2.3 years) patients who had completed a 3-year follow-up after TBI were included in the present study. APA and pituitary function were evaluated in all the patients 3 years after TBI; moreover, APAs were tested also in sera of 60 age-/sex-matched normal controls. The APAs were investigated by an indirect immunofluorescence method. Results APAs were detected in 13 out of the 29 TBI patients (44.8%), but in none of the normal controls. Pituitary dysfunction development ratio was significantly higher in APA-positive patients (46.2%) when compared with APA-negative ones (12.5%; P=0.04). There was a significant association between APA positivity and hypopituitarism due to TBI (odds ratio: 2.25, 95% confidence intervals 1.1-4.6). Moreover, there was a significant positive correlation (r=0.74, P=0.004) between APA titer ratio and peak GH response to GHRH+GH related peptide (GHRP)-6 test, suggesting that high APA titers were associated with low GH response to GHRH+GHRP-6 test.

CONCLUSIONS

This study shows for the first time the presence of the APA in TBI patients 3 years after head trauma. Moreover, present investigation indicates preliminary evidence that APA may be associated with the development of TBI-induced pituitary dysfunction, thus suggesting that autoimmunity may contribute in the development of TBI-induced hypopituitarism. The presence of the association between APA and TBI-induced hypopituitarism may provide a new point of view in this field and promote further clinical and experimental studies.

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

On the mild end of the acquired brain injury spectrum, the terms concussion and mild traumatic brain injury (mTBI) have been used interchangeably, where persistent post-concussive syndrome (PPCS) has been a label given when symptoms persist for more than three months post-concussion. Whereas a brief history of concussion research is overviewed, the focus of this review is on the current status of PPCS as a clinical entity from the perspective of recent advances in the biomechanical modeling of concussion in human and animal studies, particularly directed at a better understanding of the neuropathology associated with concussion. These studies implicate common regions of injury, including the upper brainstem, base of the frontal lobe, hypothalamic-pituitary axis, medial temporal lobe, fornix, and corpus callosum. Limitations of current neuropsychological techniques for the clinical assessment of memory and executive function are explored and recommendations for improved research designs offered, that may enhance the study of long-term neuropsychological sequelae of concussion.

Kickboxing sport as a new cause of traumatic brain injury-mediated hypopituitarism

OBJECTIVE

Traumatic brain injury, which is a frequent and a worldwide important public health problem, may result in pituitary dysfunction. Concussion, a common type of lesion after traumatic brain injury, is an injury associated with sports including boxing and kickboxing. Kickboxing is one of the most popular martial arts and approximately 1-million people around the world participate in kickboxing sport. Head is the most common site of injury in amateur and professional kickboxers. Pituitary consequences of chronic repetitive head trauma in kickboxing have not been investigated until now. Therefore, the present study was designed to investigate the pituitary function in both retired and active amateur kickboxers.

PATIENTS AND DESIGN

Twenty-two amateur kickboxers who have boxed in national and international championships (16 men, 6 women) with a mean age of 27.3 +/- 7.1 years, and 22 age- and sex-matched healthy controls were included in the study. Basal hormone levels were obtained from the participants. To assess GH-IGF-I axis, GHRH + GHRP-6 test and glucagon stimulation tests were used. Hypothalamo-pituitary-adrenal axis was assessed by glucagon stimulation test.

RESULTS

When mean basal hormone levels were compared between kickboxers and the controls, IGF-I level was significantly lower in kickboxers (P < 0.05). Five (22.7%) and two (9.1%) of the 22 kickboxers had GH deficiency had ACTH deficiency, respectively. There were significant negative correlations between IGF-I levels and age, duration of sports and number of bouts (P < 0.05).

CONCLUSIONS

Present data clearly demonstrate for the first time that amateur kickboxing is a novel cause of hypopituitarism and kickboxers are at a risk for hypopituitarism especially isolated GH deficiency. Therefore, participants of the combative sports who were exposed to chronic repetitive head trauma need to be screened.

Transient hypogonadotropic hypogonadism in an amateur kickboxer after head trauma

Traumatic brain injury (TBI) is a frequent health problem and increased prevalence of neurendocrine dysfunction in patients with TBI has been reported. Sports injuries and particularly boxing may result in pituitary dysfunction. However, transient hypogonadotropic hypogonadism after an acute head trauma due to boxing and/or kickboxing has not been defined yet. We describe the case of a 20-yr-old male amateur kickboxer who was admitted to hospital complaining of decreased libido and impotence 2 weeks after an intensive bout. Basal hormone levels were compatible with mild hyperprolactinemia and hypogonadotpopic hypogonadism. GH axis was evaluated by GHRH+GHRP-6 test and peak GH level was within normal reference range. Three months later his complaints improved and abnormalities in basal hormone levels normalized. He was also re-evaluated 9 months after the first evaluation; basal hormone levels were within normal ranges and he had no complaints. In conclusion acute head trauma due to kickboxing may cause transient gonadotropin deficiency. Therefore, screening the pituitary functions of sportsmen dealing with combative sports is crucial.

The importance of investigation of pituitary function in children and adolescents following traumatic brain injury

It is now widely accepted that brain injuries are often the cause of acquired hypopituitarism in adulthood. The information about the pituitary function in brain-injured children and adolescence is however scanty. An international workshop entitled "Traumatic brain injury and hypopituitarism" was held on 9-10 April 2006 in Granada, Spain, in order to explore the relatively unknown but potentially important field of investigation, diagnosis and treatment of pituitary deficiency in children and adolescents following traumatic brain injury (TBI). The following conclusions were reached: 1) a prospective pediatric and adolescent study of pituitary function was indicated; 2) close collaboration among neurosurgeons, neurologists, rehabilitation specialists and pediatric endocrinologists, with support from adult endocrinologists, is essential to achieve a coordinated approach to the care of children after TBI; 3) a model of interaction, similar to that now existing with oncologists, needs to be established; 4) a "pediatric TBI late-effects" service should be created, preferably led by endocrinologists, so that knowledge of growth and puberty can be included, in order to optimize identification, investigation and treatment of this important group of patients.