Pituitary dysfunction after traumatic brain injury: prevalence and screening strategies

Traumatic Brain Injury and Risk of Incident Comorbidities

Importance

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

Objective

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

Design, Setting, and Participants

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

Exposure

TBI.

Main Outcomes and Measures

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

Results

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

Conclusions and Relevance

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

Acute and chronic hypopituitarism following traumatic brain injury: a systematic review and meta-analysis

Traumatic brain injury (TBI) is associated with various endocrine abnormalities, including pituitary axis dysfunction. Understanding the prevalence and temporal patterns of these dysfunctions is crucial for effective clinical management. This study aimed to systematically review the literature and conduct a meta-analysis to determine the prevalence of pituitary axis dysfunction following TBI, assess temporal patterns across different post-injury durations, and identify potential contributing factors. A comprehensive search was conducted across multiple electronic databases between 1st of January 2000 until 31st March 2024. Studies reporting the prevalence of pituitary axis dysfunction post-TBI were included. Pooled estimates with 95% confidence intervals (CIs) were calculated using random-effects models in the R statistical software. Subgroup analyses were performed based on duration post-TBI (< 3 months, 3-6 months, 6-12 months, > 12 months) to explore temporal variations. Heterogeneity was assessed using the I^2 statistic. A total of 52 studies were included in the meta-analysis, encompassing 7367 participants. The pooled estimate for the prevalence of any pituitary axis dysfunction post-TBI was 33% (95% CI [28%; 37%]). Subgroup analysis by duration revealed varying prevalence rates: < 3 months (40%, 95% CI [27%; 53%]), 3-6 months (31%, 95% CI [15%; 47%]), 6-12 months (26%, 95% CI [19%; 33%]), and > 12 months (32%, 95% CI [26%; 38%]). Prevalence of multiple axes affection was 7% (95% CI [6%; 9%]), with varying rates across durations. Specific axes affection varied: Growth Hormone (GH) deficiency was 18% (95% CI [14%; 21%]), adrenocorticotropic hormone (ACTH) deficiency was 10% (95% CI [8%; 13%]), pituitary-gonadal axis hormones deficiency was 16% (95% CI [12%; 19%]), and thyroid-stimulating hormone (TSH) deficiency was 6% (95% CI [5%; 7%]). This meta-analysis highlights a significant prevalence of pituitary axis dysfunction following TBI, with temporal variations observed across different post-injury durations. The findings underscore the importance of tailored clinical management strategies based on the duration and type of dysfunction. Further research addressing potential contributing factors is warranted to enhance understanding and management of these conditions.

Why do patients with hypopituitarism still present an increased mortality?

Hypopituitarism is defined as a lack or decreased secretion of one or several pituitary hormones. It can result from diseases of the pituitary gland or from pathologies of the superior regulatory center, i.e. the hypothalamus, thereby decreasing hypothalamic releasing hormones and consequently the pituitary hormones. It is still a rare disease with an estimated prevalence of 30-45 patients/100,000 and an incidence of 4-5/100,000/year. This review summarizes the currently available data with a focus on etiologies of hypopituitarism, evidence on mortality rates in patients with hypopituitarism, temporal trends in mortality , and associated diseases, pathophysiological mechanisms and risk factors that affect mortality risk in these patients.

The left-right side-specific endocrine signaling in the effects of brain lesions: questioning of the neurological dogma

Each cerebral hemisphere is functionally connected to the contralateral side of the body through the decussating neural tracts. The crossed neural pathways set a basis for contralateral effects of brain injury such hemiparesis and hemiplegia as it has been already noted by Hippocrates. Recent studies demonstrated that, in addition to neural mechanisms, the contralateral effects of brain lesions are mediated through the humoral pathway by neurohormones that produce either the left or right side-specific effects. The side-specific humoral signaling defines whether the left or right limbs are affected after a unilateral brain injury. The hormonal signals are released by the pituitary gland and may operate through their receptors that are lateralized in the spinal cord and involved in the side-specific control of symmetric neurocircuits innervating the left and right limbs. Identification of features and a proportion of neurological deficits transmitted by neurohormonal signals vs. those mediated by neural pathways is essential for better understanding of mechanisms of brain trauma and stroke and development of new therapies. In a biological context, the left-right side-specific neuroendocrine signaling may be fundamental for the control of the left- and right-sided processes in bilaterally symmetric animals.

Preoperative Magnetic Resonance Imaging Localization of the Normal Pituitary Gland in Nonfunctioning Pituitary Adenoma Patients Using the Radiological Sign of "Internal Carotid Artery Notch"

OBJECTIVE

Asymmetric features of nonfunctioning pituitary adenoma (NFPA) are poorly understood. We investigated the asymmetry in NFPA on magnetic resonance imaging.

METHODS

We reviewed preoperative magnetic resonance imaging findings of patients initially treated for NFPA. The internal carotid artery (ICA) often seemed to cause an indentation in the external shape of the tumor (i.e., the ICA notch).

RESULTS

Two cases with a normal pituitary gland located at the midline were excluded. The remaining 66 cases were examined. The side where the normal gland was located was defined as the normal pituitary side and the opposite side as the cavernous sinus side. The Knosp grade was significantly higher on the cavernous sinus side (P < 0.001), and the vertical distance of the ICA was significantly greater on the cavernous sinus side (P < 0.001). The ICA notch was found in 87.9% of all cases on the normal pituitary side, but in only 45.5% on the cavernous sinus side (P < 0.001). In cases with a single-side ICA notch (34 of 68), the ICA notch was found in 91.2% of cases and on the cavernous sinus side in 8.8% (P < 0.001).

CONCLUSIONS

Magnetic resonance imaging of NFPA frequently shows asymmetry. The tumor does not extend laterally on the normal pituitary side but extends laterally more freely on the cavernous sinus side. The ICA notch is often found on the normal pituitary side where the position of ICA does not move. This may be useful as a preoperative sign to indicate the normal pituitary side.

Future Perspectives in Spinal Cord Repair: Brain as Saviour? TSCI with Concurrent TBI: Pathophysiological Interaction and Impact on MSC Treatment

Traumatic spinal cord injury (TSCI), commonly caused by high energy trauma in young active patients, is frequently accompanied by traumatic brain injury (TBI). Although combined trauma results in inferior clinical outcomes and a higher mortality rate, the understanding of the pathophysiological interaction of co-occurring TSCI and TBI remains limited. This review provides a detailed overview of the local and systemic alterations due to TSCI and TBI, which severely affect the autonomic and sensory nervous system, immune response, the blood-brain and spinal cord barrier, local perfusion, endocrine homeostasis, posttraumatic metabolism, and circadian rhythm. Because currently developed mesenchymal stem cell (MSC)-based therapeutic strategies for TSCI provide only mild benefit, this review raises awareness of the impact of TSCI-TBI interaction on TSCI pathophysiology and MSC treatment. Therefore, we propose that unravelling the underlying pathophysiology of TSCI with concomitant TBI will reveal promising pharmacological targets and therapeutic strategies for regenerative therapies, further improving MSC therapy.

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.