Neuroendocrine Abnormalities Following Traumatic Brain Injury: An Important Contributor to Neuropsychiatric Sequelae (original) (raw)

Hypopituitarism following traumatic brain injury: determining factors for diagnosis

Frontiers in Endocrinology, 2011

Neuroendocrine dysfunction, long recognized as a consequence of traumatic brain injury (TBI), is a major cause of disability that includes physical and psychological involvement with long-term cognitive, behavioral, and social changes. There is no standard procedure regarding at what time after trauma the diagnosis should be made. Also there is uncertainty on defining the best methods for diagnosis and testing and what types of patients should be selected for screening. Common criteria for evaluating these patients are required on account of the high prevalence of TBI worldwide and the potential new cases of hypopituitarism. The aim of this review is to clarify, based on the evidence, when endocrine assessment should be performed after TBI and which patients should be evaluated. Additional studies are still needed to know the impact of post-traumatic hypopituitarism and to assess the impact of hormone replacement in the prognosis.

Neuropsychology of Neuroendocrine Dysregulation after Traumatic Brain Injury

Journal of clinical medicine, 2015

Endocrine dysfunction is a common effect of traumatic brain injury (TBI). In addition to affecting the regulation of important body functions, the disruption of endocrine physiology can significantly impair mental functions, such as attention, memory, executive function, and mood. This mini-review focuses on alterations in mental functioning that are associated with neuroendocrine disturbances in adults who suffered TBI. It summarizes the contribution of hormones to the regulation of mental functions, the consequences of TBI on mental health and neuroendocrine homeostasis, and the effects of hormone substitution on mental dysfunction caused by TBI. The available empirical evidence suggests that comprehensive assessment of mental functions should be standard in TBI subjects presenting with hormone deficiency and that hormone replacement therapy should be accompanied by pre- and post-assessments.

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

Journal of Clinical Medicine, 2015

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.

Neuroendocrine dysfunction in the acute phase of traumatic brain injury

Clinical Endocrinology, 2004

BACKGROUND Pituitary hormone abnormalities have been reported in up to 50% of survivors of traumatic brain injury ( TBI) who were investigated several months or longer following the event. The frequency of pituitary dysfunction in the early post-TBI period is unknown. AIM To evaluate the prevalence of anterior and posterior pituitary dysfunction in the early phase following TBI. SUBJECTS Fifty consecutive patients admitted to the neurosurgical unit with severe or moderate TBI [initial Glasgow Coma Scale (GCS) score 3 -13], and 31 matched healthy control volunteers were studied. METHODS The glucagon stimulation test (GST) was performed at a median of 12 days (range 7-20) following TBI. Baseline thyroid function, PRL, IGF-1, gonadotrophins, testosterone or oestradiol, plasma sodium, plasma and urine osmolalities or the standard observed water deprivation test were performed. The control subjects underwent the GST for GH and cortisol responses; other parameters were compared to locally derived reference ranges. RESULTS Control data indicated that peak serum GH of > 5 ng / ml and cortisol > 450 nmol/l following glucagon stimulation should be taken as normal. Nine TBI patients (18%) had GH response < 5 ng/ml (12 mU/l). Eight patients (16%) had peak cortisol responses < 450 nmol/l. Compared to controls, basal cortisol values were significantly lower in patients with subnormal cortisol responses to glucagon and significantly higher in patients with normal cortisol responses ( P < 0·05). GH and cortisol deficiencies were unrelated to patient age, BMI, initial GCS or IGF-1 values ( P > 0·05). Forty patients (80%) had gonadotrophin deficiency, with low sex steroid concentrations, which was unrelated to the presence of hyperprolactinaemia. In males there was a positive correlation between serum testosterone concentration and GCS ( r = 0·32, P = 0·04). One patient had TSH deficiency. Hyperprolactinaemia was present in 26 patients (52%) and serum PRL levels correlated negatively with the GCS score ( r = − − − − 0·36, P = 0·011). Thirteen patients (26%) had cranial diabetes insipidus (DI) and seven (14%) had syndrome of inappropriate ADH secretion. CONCLUSION Our data show that post-traumatic neuroendocrine abnormalities occur early and with high frequency, which may have significant implications for recovery and rehabilitation of TBI patients.

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

Neurocritical Care

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 b...

Hypopituitarism following traumatic brain injury

Growth Hormone & IGF Research, 2005

Recent studies have demonstrated that hypopituitarism, and in particular growth hormone (GH) deficiency, is common among survivors of traumatic brain injury (TBI) tested several months or years following head trauma. In addition, it has been shown that post-traumatic neuroendocrine abnormalities occur early and with high frequency. These findings may have significant implications for the recovery and rehabilitation of patients with TBI. Although data emerging after 2000 demonstrate the relevance of the problem, in general there is a lack of awareness in the medical community about the incidence and clinical repercussions of the pathology. Most, but not all, head trauma associated with hypopituitarism is the result of motor accidents. The subjects at risk are those who have suffered moderate-to severe head trauma although mild intensity trauma may precede hypopituitarism also. Particular attention should be paid to this problem in children and adolescents. Onset of pituitary deficits can evolve over years following injury. For the assessment of the GH-IGF axis in TBI patients, plasma IGF-I concentrations, plus dynamic GH testing is indicated. Some degree of hypopituitarism is found in 35-40% of TBI patients. Among multiple pituitary deficits, the most common ones were GHD and gonadotrophin deficiency. In most series 10-15% presented with severe GHD and 15% with partial GHD after stimulating GH secretion confirming that the most common isolated deficit is GHD. Psychometric evaluation together with neurocognitive testing shows variability of disability and the possibility that untreated TBI induced hypopituitarism contributes to the chronic neurobehavioral problems seen in many head-injured patients warrants consideration. Preliminary data, from small pilot, open-label studies show that subjects treated with GH experience significant improvements in concentration, memory, depression, anxiety and fatigue. In conclusion, pituitary failure can occur even in minor head injuries and is poorly recognized.

Endocrine dysfunction in the immediate period following traumatic brain injury

Critical Care, 2003

Studies on head injury-induced pituitary dysfunction are limited in number and conflicting results have been reported. To further clarify this issue, 29 consecutive patients (24 males), with severe (n = 21) or moderate (n = 8) head trauma, having a mean age of 37 ± 17 years were investigated in the immediate post-trauma period. All patients required mechanical ventilatory support for 8-55 days and were enrolled in the study within a few days before ICU discharge. Basal hormonal assessment included measurement of cortisol, corticotropin, free thyroxine (fT4), thyrotropin (TSH), testosterone (T) in men, estradiol (E2) in women, prolactin (PRL), and growth hormone (GH). Cortisol and GH levels were measured also after stimulation with 100 µg human corticotropin releasing hormone (hCRH) and 100 µg growth hormone releasing hormone (GHRH), respectively. Cortisol hyporesponsiveness was considered when peak cortisol concentration was less than 20 µg/dl following hCRH. TSH deficiency was diagnosed when a subnormal serum fT4 level was associated with a normal or low TSH. Hypogonadism was considered when T (males) or E2 (women) were below the local reference ranges, in the presence of normal PRL levels. Severe or partial GH deficiencies were defined as a peak GH below 3 µg/l or between 3 and 5 µg/l, respectively, after stimulation with GHRH. Twenty-one subnormal responses were found in 15 of the 29 patients (52%) tested; seven (24%) had hypogonadism, seven (24%) had cortisol hyporesponsiveness, five (17%) had hypothyroidism, and two patients (7%) had partial GH deficiency. These preliminary results suggest that a certain degree of hypopituitarism occurs in more than 50% of patients with moderate or severe head injury in the immediate post-trauma period, with cortisol hyporesponsiveness and hypogonadism being most common. Further studies are required to elucidate the pathogenesis of these abnormalities and to investigate whether they affect long-term morbidity. P2 Cortisol reserve in head trauma victims: evaluation with the low-dose (1 µ µg) corticotropin (ACTH) stimulation test

Anterior pituitary dysfunction following traumatic brain injury (TBI)

Clinical Endocrinology, 2006

Traumatic brain injury (TBI) is the commonest cause of death and disability in young adults living in industrialized countries. Several recent studies have convincingly shown that anterior hypopituitarism is a common complication of head trauma with a prevalence of at least 25% among long-term survivors. This is a much higher frequency than previously thought and suggests that most cases of post-traumatic hypopituitarism (PTHP) remain undiagnosed and untreated. These findings raise important questions about the potential contribution of PTHP to the high physical and neuropsychiatric morbidity seen in this group of patients. In this review, we examine the published reports on the neuroendocrine abnormalities in TBI patients and highlight new data that give novel insights into the natural history of this disorder. We discuss the potential contribution of PTHP to recovery and rehabilitation after injury and the need for the identification and the appropriate and timely management of hormone deficiencies to optimize patient recovery from head trauma, improve quality of life and avoid the long-term adverse consequences of untreated hypopituitarism.

Endocrine consequences of traumatic brain injury. Literature review

Romanian Journal of Legal Medicine, 2016

Traumatic brain injury (TBI) is associated with increased mortality and morbidity, as well as high rates of longterm disability in survivors. TBI-related deficiencies of both anterior pituitary (posttraumatic hypopituitarism, PTHP) and posterior pituitary (diabetes insipidus PTDI or syndrome of inappropriate antidiuretic secretion, SIADH) are much more frequent than previously known and associated with an unfavourable outcome. The pathophysiology of pituitary dysfunction after TBI is not entirely clear. The traumatic event can induce skull base fractures, hemorrhages or infarction affecting the hypothalamic and pituitary region with consequent endocrine dysfunction. In addition, metabolic and vascular brain changes, frequent in a critically ill patient also aggravate the neuroendocrine dysfunction. In the first days after trauma, the deficiency of adrenocorticotropic hormone and PTDI or SIADH are the main concern because if undiagnosed and untreated are associated with severe dyselectrolitemia and hypotension with increased mortality rate. Posterior pituitary dysfunction occurs in the first days after injury; SIADH usually resolves completely, PTDI can persist in a minority of cases. In contrast, PTHP can occur after a long time interval after TBI. Some degree of PTHP is present in 30-40% of TBI survivors. Early recognition and endocrinological treatment are essential to optimize the outcome of the intensive care management and of the rehabilitation process.

The natural history of post-traumatic hypopituitarism: Implications for assessment and treatment

The American Journal of Medicine, 2005

PURPOSE: Hypopituitarism has been reported in up to half of long-term survivors of traumatic brain injury. We attempted to define the natural history of post-traumatic hypopituitarism to devise guidelines for the optimal timing of patients' assessment and hormone replacement. SUBJECTS AND METHODS: Fifty consecutive patients with severe or moderate head trauma were enrolled in a prospective study of pituitary function during the acute phase, at 6 months, and at 12 months after injury. Growth hormone and adrenocorticotropin hormone reserves were assessed using the glucagon stimulation test. Baseline serum concentrations of other anterior pituitary hormones were measured. Results were compared with normative data obtained from matched healthy controls. RESULTS: Nine patients (18%) had growth hormone deficiency in the acute phase; at 6 months, 5 patients recovered function and 2 new deficiencies were detected; at 12 months, 1 patient recovered, leaving 5 patients (10%) with growth hormone deficiency. Eight patients (16%) showed subnormal cortisol response in the acute phase; at 6 months, 4 patients had recovered and 5 new deficiencies were detected; all 9 patients had persistent abnormalities at 2 months. Forty patients (80%) had gonadotropin deficiency in the acute phase, of whom 29 (73%) recovered by 6 months and 34 (85%) recovered by 12 months. Thyrotropin deficiency was present in 1 patient in the acute phase, who recovered by 6 months; 1 new case was diagnosed at 6 months, which persisted at 12 months. CONCLUSION: After traumatic brain injury, early neuroendocrine abnormalities are sometimes transient, whereas late abnormalities present during the course of rehabilitation. A follow-up strategy with periodic evaluation is a necessary part of the optimal care for patients with traumatic brain injury. Traumatic brain injury is increasingly common in industrialized countries, causing the death or hospital admission of 180 to 250 persons per 100 000 per year. 1 Data from retrospective cross-sectional studies indicate that hypopituitarism occurs in up to half of long-term survivors of head injury. 2-5 Because hypopituitarism is a potentially important but treatable cause of morbidity or even mortality after brain trauma, some authors have recommended that screening for post-traumatic hypopituitarism should become part of routine clinical care. 4,5 However, the lack of information about the natural history of post-traumatic pituitary dysfunction precludes the development of evidence-based guidelines for