Chronic glucocorticoid hypersecretion in Cushing's syndrome exacerbates cognitive aging

Glucocorticoids and cognitive function: a walkthrough in endogenous and exogenous alterations

PURPOSE

The hypothalamic-pituitary-adrenal (HPA) axis exerts many actions on the central nervous system (CNS) aside from stress regulation. Glucocorticoids (GCs) play an important role in affecting several cognitive functions through the effects on both glucocorticoid (GR) and mineralocorticoid receptors (MR). In this review, we aim to unravel the spectrum of cognitive dysfunction secondary to derangement of circulating levels of endogenous and exogenous glucocorticoids.

METHODS

All relevant human prospective and retrospective studies published up to 2022 in PubMed reporting information on HPA disorders, GCs, and cognition were included.

RESULTS

Cognitive impairment is commonly found in GC-related disorders. The main brain areas affected are the hippocampus and pre-frontal cortex, with memory being the most affected domain. Disease duration, circadian rhythm disruption, circulating GCs levels, and unbalanced MR/GR activation are all risk factors for cognitive decline in these patients, albeit with conflicting data among different conditions. Lack of normalization of cognitive dysfunction after treatment is potentially attributable to GC-dependent structural brain alterations, which can persist even after long-term remission.

CONCLUSION

The recognition of cognitive deficits in patients with GC-related disorders is challenging, often delayed, or mistaken. Prompt recognition and treatment of underlying disease may be important to avoid a long-lasting impact on GC-sensitive areas of the brain. However, the resolution of hormonal imbalance is not always followed by complete recovery, suggesting irreversible adverse effects on the CNS, for which there are no specific treatments. Further studies are needed to find the mechanisms involved, which may eventually be targeted for treatment strategies.

Neuroendocrine pathogenesis of perimenopausal depression

With the development of social economics and the increase of working pressure, more and more women are suffering from long-term serious stress and showing symptoms of perimenopausal depression (PMD). The incidence rate of PMD is increasing, and the physical and mental health are seriously affected. However, due to the lack of accurate knowledge of pathophysiology, its diagnosis and treatment cannot be accurately executed. By consulting the relevant literature in recent years, this paper elaborates the neuroendocrine mechanism of perimenopausal depression from the aspects of epigenetic changes, monoamine neurotransmitter and receptor hypothesis, glial cell-induced neuroinflammation, estrogen receptor, interaction between HPA axis and HPG axis, and micro-organism-brain gut axis. The purpose is to probe into new ways of treatment of PMD by providing new knowledge about the neuroendocrine mechanism and treatment of PMD.

Gene expression changes in the brain of a Cushing's syndrome mouse model

Excess glucocorticoid exposure affects emotional and cognitive brain functions. The extreme form, Cushing's syndrome, is adequately modelled in the AdKO_2.0 mouse, consequential to adrenocortical hypertrophy and hypercorticosteronemia. We previously reported that the AdKO_2.0 mouse brain undergoes volumetric changes that resemble closely those of Cushing's syndrome human patients, as well as changes in expression of glial related marker proteins. In the present work, the expression of genes related to glial and neuronal cell populations and functions was assessed in regions of the anterior brain, hippocampus, amygdala and hypothalamus. Glucocorticoid target genes were consistently regulated, including CRH mRNA suppression in the hypothalamus and induction in amygdala and hippocampus, even if glucocorticoid receptor protein was downregulated. Expression of glial genes was also affected in the AdKO_2.0 mouse brain, indicating a different activation status in glial cells. Generic markers for neuronal cell populations, and cellular integrity were only slightly affected. Our findings highlight the vulnerability of glial cell populations to chronic high levels of circulating glucocorticoids.

Potential associations between immune signaling genes, deactivated microglia, and oligodendrocytes and cortical gray matter loss in patients with long-term remitted Cushing's disease

INTRODUCTION

Cushing's disease (CD) is a rare and severe endocrine disease characterized by hypercortisolemia. Previous studies have found structural brain alterations in remitted CD patients compared to healthy controls, specifically in the anterior cingulate cortex (ACC). However, potential mechanisms through which these persistent alterations may have occurred are currently unknown.

METHODS

Structural 3T MRI's from 25 remitted CD patients were linked with gene expression data from neurotypical donors, derived from the Allen Human Brain Atlas. Differences in gene expression between the ACC and an unaffected control cortical region were examined, followed by a Gene Ontology (GO) enrichment analysis. A cell type enrichment analysis was conducted on the differentially expressed genes, and a disease association enrichment analysis was conducted to determine possible associations between differentially expressed genes and specific diseases. Subsequently, cortisol sensitivity of these genes in existing datasets was examined.

RESULTS

The gene expression analysis identified 300 differentially expressed genes in the ACC compared to the cortical control region. GO analyses found underexpressed genes to represent immune function. The cell type specificity analysis indicated that underexpressed genes were enriched for deactivated microglia and oligodendrocytes. Neither significant associations with diseases, nor evidence of cortisol sensitivity with the differentially expressed genes were found.

DISCUSSION

Underexpressed genes in the ACC, the area vulnerable to permanent changes in remitted CD patients, were often associated with immune functioning. The specific lack of deactivated microglia and oligodendrocytes implicates protective effects of these cell types against the long-term effects of cortisol overexposure.

Endocrine dysfunction and cognitive impairment

Dementia is a highly prevalent chronic disease among the older population, affecting more than 50 million people worldwide and representing a huge healthcare, social and economic burden. Dementia, and in particular Alzheimer's disease, prevalence is expected to raise within the next few years. Unfortunately, no disease-modifying therapies are available so far, despite a plethora of clinical trials targeting the hallmarks of Alzheimer's disease. Given these premises, it appears crucial to address not only the neuropathological correlates of the disease, but also the modifiable risk factors. Among them, evidence suggest a role of the endocrine system not only in the brain development, but also in the maintenance of its health, having neurotrophic, antioxidant and metabolic functions crucial for the cognitive abilities. This review focuses on the evidence evaluating the impact of the endocrine systems, in particular thyroid function, insulin resistance, parathyroid hormone, vitamin D and sexual hormones on cognitive status. Results from epidemiological, preclinical and some clinical studies demonstrated the link between thyroid, parathyroid hormone and vitamin D and cognitive status, between diabetes, and insulin resistance in particular, and dementia, between sexual and adrenal hormones, particularly estrogen variation at menopause, and cognitive decline. The growing interest on the modifiable risks factors of cognitive decline increased the knowledge about the complex interplay of endocrine systems and cognition, highlighting the need and the usefulness of a multidisciplinary approach to the prevention of a complex and devastating disease.

Neuropsychological Functioning in Patients with Cushing's Disease and Cushing's Syndrome

PURPOSE

To present a systematic review of the presence and severity of neuropsychological impairment in the six main neuropsychological domains (attention, executive function, language, visuospatial processing, intelligence, and memory) in patients with Cushing's disease (CD) and/or Cushing's Syndrome (CS) at various stages of the illness. The work aims to identify neuropsychological leverage points for focused diagnosis and rehabilitation in CS/CD patients.

METHODS

A pubmed literature search was performed and augmented by searching the reference lists of review articles identified by this search strategy. After excluding irrelevant hits, we systematically extracted data from 27 studies for each main neuropsychological domain, differentiating between active disease, short- and long-term remission.

RESULTS

The literature gives evidence for neuropsychological impairment in all domains in Cushing patients with active disease. The most consistent impairments concerned memory and visuo-spatial processing, whereas the data are discordant for all other domains. Significant improvement of neuropsychological function - although not returning to normal in all domains - is shown in short-term and long-term remission of the disease. However, the published literature is thin, suffering from repetitive subsample analyses publishing, methodological concerns as lack of control for confounders such as depression.

CONCLUSIONS

Memory is the most extensively investigated domain in CS/CD patients and impairment is most prominent in active disease. Patients should be counseled that neuropsychological function will improve with normalization of hypercortisolism and over time. More studies with more stringent methodological criteria, larger patient samples and controlling for confounders are required to enhance our understanding of neuropsychological function in patients with CS/CD.

Aberrant DNA methylation of synaptophysin is involved in adrenal cortisol-producing adenoma

Cortisol-producing adenoma (CPA) is the main cause of Adrenal Cushing syndrome. However, its molecular mechanism is not fully understood. Previous study revealed Synaptophysin (SYP) is ubiquitously expressed in adrenocortical tumors, but its function in CPA still need to be discovered. In the present study we determine the molecular mechanism involved in SYP dysregulation in CPA and how SYP affects the secretion of cortisol in CPA. Our results showed that aberrant DNA methylation of SYP is involved in CPA progress. Using a miRNA microarray and qRT-PCR, we found decreased expression of miR-27a-5p in CPA compared with normal adrenal tissue. Moreover, the expression of TET3, the target gene of miR-27a-5p, increased in CPA compared with normal adrenal tissue. Knock-down of TET3 resulted in hypermethylation of SYP which reducing the expression level of SYP in H295R cells. The miR-27a-5p-TET3-SYP signalling pathway may regulate proliferation and cortisol secretion in H295R cells and, thus, play a key role in CPA development.

Quality of Life in Patients With Cushing's Disease

Cushing's disease (and by extension, Cushing's syndrome) is a rare disease due to a chronic cortisol excess, which usually has an important impact on quality of life (QoL). It can lead to numerous comorbidities that can interfere with daily life, as fatigability, myopathy, bone loss and fragility, increased cardiovascular risk, depression, and cognitive alterations. Of note, psychological alterations (including depression and anxiety) occur often, and are an important determinant of impaired quality QoL. QoL scores using different questionnaires are poorer in comparison to healthy controls, other pituitary adenomas and some chronic diseases. Even if some improvements can be observed after successful treatment, recovery does not seem to be complete, and comorbidities persist. This persistent QoL impairment has been found using both generic and disease-specific QoL questionnaires, and is also reported by the patients themselves, when asked directly. Multidisciplinary teams are essential to improve patients' well-being. Clinicians should take into account the whole scope of clinical problems and address the different comorbidites associated with the disease. Screening in the psychological sphere, with further intervention if necessary, can be helpful in the management of these patients. Interventions and programs have shown promising results, although there is a need for further development of new strategies for the benefit of these patients.

The dysfunction of processing task-irrelevant emotional faces in pituitary patients: an evidence from expression-related visual mismatch negativity

Evidence showed impaired cognitive ability of patients with pituitary adenoma as an intracranial tumor. In the present study, we investigated the preattentive processing of emotional faces in pituitary adenoma patients by recording and analyzing the visual mismatch negativity elicited by deviant emotional faces. In the normal control group, deviant emotional faces elicited expression-related mismatch negativity (EMMN), with a more pronounced negative waveform for sad than happy face conditions. Compared with the normal group, EMMN related to sad faces was smaller in patients, whereas the EMMN related to happy faces remained the same. These data indicate the functional dysfunction of negative emotional processing at the preattentive stage of information processing in pituitary adenoma patients.

The dysfunction of inhibition control in pituitary patients: evidence from the Go/Nogo event-related potential study

Pituitary tumor is an intracranial tumor; because of the development of neuroimaging technology in recent years, morbidity is likely to increase. Evidence showed impaired cognitive ability of patients with pituitary adenoma. There is evidence that neurobehavioral disorders are common in pituitary adenoma patients. This disorder is because of the cognitive and emotional function of the important functional areas of the brain oppressed and hormone imbalance. Individuals' mental activity is controlled by the brain and the abnormal mental activity is caused by both the structural abnormalities of the brain and neurochemical dysfunction. Event-related potentials have been used widely in the early assessment of cognitive functions associated with disease, taking advantage of the high temporal resolution, and then analyzing the characteristics of emotional competence from the perspective of cognitive processing. A visual Go/Nogo task was used. A larger Nogo-N2 and Nogo-P3 was found in the control group compared with the pituitary group. This reflects the nonphysiological process of conflict monitoring and inhibitory control in pituitary patients. The results also showed that the difference waves between Go and Nogo conditions (N2d and P3d) over the frontal electrode sites were more robust and earlier in the control group compared with the pituitary group, which reflects frontal dysfunction in the pituitary group. These data suggest reduced earlier and later stages of inhibitory processes in pituitary individuals, implicating the dysfunction of conflict detection and inhibitory control.

An Integrated Model of Chronic Whiplash-Associated Disorder

Synopsis The development of persistent symptoms following whiplash injury from a motor vehicle collision is common and contributes substantially to societal and personal costs. The popular Quebec Task Force classification system of whiplash-associated disorders (WADs) was meant to function as a prognostic and intervention decision aid, but its usefulness has been questioned. Emerging evidence highlights the heterogeneity of WAD by demonstrating physical and psychological impairments that are unique to those who develop persistent symptoms. These impairments are not recognized in the Quebec Task Force classification system. The purpose of this clinical commentary is to describe an integrated model that focuses on how psychological and neurobiological factors interact with, and are influenced by, existing personal and environmental factors to contribute to the development of chronic WAD. The model has been developed through more than 20 years of work in the field, consultation with experts, in-depth synthesis of existing evidence, and new evidence from the authors' own research programs. A subtheme is that a point of convergence currently exists between the psychological, physiological, and social determinants of health literature that can further explain the complex presentation of WAD. The new model is proposed to orient future research toward more interdisciplinary efforts across nontraditional fields, including data scientists and consumers, to clarify the WAD condition. J Orthop Sports Phys Ther 2017;47(7):462-471. Epub 16 Jun 2017. doi:10.2519/jospt.2017.7455.

Psychiatric Symptoms in Patients with Cushing's Syndrome: Prevalence, Diagnosis and Management

Cushing's syndrome (CS) results from chronic exposure to cortisol excess, produced by the adrenal cortex. Hypercortisolism predisposes to psychiatric and neurocognitive disorders, mainly to depression and anxiety disorders. Screening tools to identify psychiatric symptoms are available for clinicians in their daily practice, although a specific diagnosis should be performed by specialists. Even if psychiatric symptoms improve after remission of hypercortisolism, complete recovery may not be achieved. Given the burden of these symptoms, psychiatric or psychological monitoring and treatment should be offered through all phases of CS, with a multidisciplinary approach. The aim of this article is to review data on the prevalence, diagnosis and management of psychiatric symptoms seen in patients with CS and to propose therapeutic approaches that may be followed in clinical practice. The prevalence of different psychiatric disorders has been described in both the active phase and after CS remission. Patients may not talk spontaneously about psychiatric symptoms they present, thus clinicians should ask directly about them. We recommend the use of screening tools in clinical practice to detect and treat these symptoms promptly. Even if reference endocrinologists cannot perform a definite psychiatric diagnosis, it will be important to ask patients directly about the presence of symptoms and refer if necessary to a psychiatrist. Additionally, patient information and educational programmes could be useful to manage psychiatric symptoms and to improve quality of life in patients with CS.

Associations between hippocampal morphology, diffusion characteristics, and salivary cortisol in older men

High, unabated glucocorticoid (GC) levels are thought to selectively damage certain tissue types. The hippocampus is thought to be particularly susceptible to such effects, and though findings from animal models and human patients provide some support for this hypothesis, evidence for associations between elevated GCs and lower hippocampal volumes in older age (when GC levels are at greater risk of dysregulation) is inconclusive. To address the possibility that the effects of GCs in non-pathological ageing may be too subtle for gross volumetry to reliably detect, we analyse associations between salivary cortisol (diurnal and reactive measures), hippocampal morphology and diffusion characteristics in 88 males, aged ∼73 years. However, our results provide only weak support for this hypothesis. Though nominally significant peaks in morphology were found in both hippocampi across all salivary cortisol measures (standardised β magnitudes<0.518, p_uncorrected>0.0000003), associations were both positive and negative, and none survived false discovery rate correction. We found one single significant association (out of 12 comparisons) between a general measure of hippocampal diffusion and reactive cortisol slope (β=0.290, p=0.008) which appeared to be driven predominantly by mean diffusivity but did not survive correction for multiple testing. The current data therefore do not clearly support the hypothesis that elevated cortisol levels are associated with subtle variations in hippocampal shape or microstructure in non-pathological older age.

Brain metabolite abnormalities in ventromedial prefrontal cortex are related to duration of hypercortisolism and anxiety in patients with Cushing's syndrome

Chronic exposure to excessive glucocorticoid (GC) concentration in Cushing's syndrome (CS) can affect the brain structurally and functionally; ventromedial prefrontal cortex (vmPFC) is rich in GC receptors and therefore particularly vulnerable to excessive GC concentration. Proton magnetic resonance spectroscopy ((1)H-MRS) is a sensitive, non-invasive imaging technique that provides information on brain metabolites in vivo. Our aim was to investigate metabolite concentrations in vmPFC of CS patients and their relationship with clinical outcome. Twenty-two right-handed CS patients (7 active/15 in remission, 19 females, 41.6 ± 12.3 years) and 22 right-handed healthy controls (14 females, 41.7 ± 11 years) underwent brain MRI and (1)H-MRS exams at 3 Tesla. Concentrations of glutamate (Glu), glutamate + glutamine (Glx), creatine (Cr), N-Acetyl-aspartate (NAA), N-Acetyl-aspartate + N-acetylaspartylglutamate (total NAA), choline-containing compounds (Cho) and myoinositol (MI) were determined. Moreover, anxiety and depressive symptoms were evaluated with the State-Trait Anxiety Inventory (STAI) and the Beck Depression Inventory-II (BDI-II) test, respectively. CS patients had lower concentrations of glutamate and total NAA in the vmPFC than healthy controls (8.6 ± 1.2 vs. 9.3 ± 0.7 mmol/L, and 6.4 ± 0.8 vs. 6.8 ± 0.4 mmol/L, respectively; p < 0.05). Duration of hypercortisolism was negatively correlated with total NAA (r = -0.488, p < 0.05). Moreover, the concentration of total NAA was negatively correlated with anxiety state (r = -0.359, p < 0.05). Brain metabolites are abnormal in the vmPFC of patients with CS. Decreased total NAA and glutamate concentrations indicate neuronal dysfunction that appear to be related with duration of hypercortisolism and anxiety.

Cases of Psychiatric Morbidity in Pediatric Patients After Remission of Cushing Syndrome

Endogenous Cushing syndrome (CS) may have different effects in children than what has been described in adults. Previous studies of children and adolescents with CS have identified cognitive decline despite reversal of brain atrophy after remission of CS. Although the observations of parents of children and adolescents with CS support personality changes, significant psychopathology has not been described in the literature. We report 9 children who underwent successful surgery (transsphenoidal surgery [TSS] or resection of bronchial carcinoid) for treatment of CS and subsequently developed significant affective pathology. Affective symptoms included anger-rage outbursts, suicidal ideation, irritability, anxiety, and depression. One child, who committed suicide 60 months after TSS, had recently discontinued antidepressant medication. She had a history of anxiety during active CS and was treated with an anxiolytic. The 7 patients with onset of symptoms within 7 months of TSS were on glucocorticoid replacement, and 1-year follow-up evaluation showed recovery of hypothalamic-pituitary-adrenal axis and biochemical evidence of remission. The 2 patients who presented with onset of symptoms at 48 months or later underwent endocrine evaluation that showed biochemical evidence of remission and normal anterior pituitary hormone levels. This is the first report of affective symptoms and behavioral dysregulation, including suicidal ideation, in a subgroup of children and adolescents after remission of CS. Health care providers caring for children with CS who have been cured should continue to screen for mental illness, monitor for changes in behavior, and refer as appropriate to mental health professionals.

Long-term cognitive effects of glucocorticoid excess in Cushing's syndrome

CONTEXT AND OBJECTIVE

We previously found that patients with Cushing's syndrome (CS) scored lower than controls in several domains of cognitive function and that correction of hypercortisolism is not necessarily correlated with short-term improvement in intellectual performance. Here, we examined the long-term outcome in patients treated for CS by assessing the extent to which the detrimental effects of glucocorticoid (GC) excess on cognition can be reversed three years after corrective surgery.

DESIGN

A battery of neuropsychological tests, including tests of attention, visuospatial processing, learning and memory, and executive functioning were administered pre-treatment and 12, 24 and 36 months post-treatment.

PATIENTS AND CONTROL SUBJECTS

We included 18 patients with endogenous CS recruited before surgical treatment and 18 controls matched for age, sex and education.

RESULTS

CS patients performed worse than controls on tests of attention, executive functioning and nonverbal aspects of memory. Moreover, at 36 months following eucortisolism, executive function performance and, to a lesser extent, attention tasks showed limited change compared to pre-treatment testing.

CONCLUSION

Chronic hypercortisolism is accompanied by a deleterious impact on aspects of cognitive function. This negative effect on attention, executive performance and nonverbal memory seen in patients with CS suggests a differential effect of excess GCs upon different brain areas and networks. This influence persists years after the return to normal cortisol secretion levels.

Glucocorticoid Regulation of Food-Choice Behavior in Humans: Evidence from Cushing's Syndrome

The mechanisms by which glucocorticoids regulate food intake and resulting body mass in humans are not well-understood. One potential mechanism could involve modulation of reward processing, but human stress models examining effects of glucocorticoids on behavior contain important confounds. Here, we studied individuals with Cushing's syndrome, a rare endocrine disorder characterized by chronic excess endogenous glucocorticoids. Twenty-three patients with Cushing's syndrome (13 with active disease; 10 with disease in remission) and 15 controls with a comparably high body mass index (BMI) completed two simulated food-choice tasks (one with “explicit” task contingencies and one with “probabilistic” task contingencies), during which they indicated their objective preference for viewing high calorie food images vs. standardized pleasant, unpleasant, and neutral images. All participants also completed measures of food craving, and approximately half of the participants provided 24-h urine samples for assessment of cortisol and cortisone concentrations. Results showed that on the explicit task (but not the probabilistic task), participants with active Cushing's syndrome made fewer food-related choices than participants with Cushing's syndrome in remission, who in turn made fewer food-related choices than overweight controls. Corroborating this group effect, higher urine cortisone was negatively correlated with food-related choice in the subsample of all participants for whom these data were available. On the probabilistic task, despite a lack of group differences, higher food-related choice correlated with higher state and trait food craving in active Cushing's patients. Taken together, relative to overweight controls, Cushing's patients, particularly those with active disease, displayed a reduced vigor of responding for food rewards that was presumably attributable to glucocorticoid abnormalities. Beyond Cushing's, these results may have relevance for elucidating glucocorticoid contributions to food-seeking behavior, enhancing mechanistic understanding of weight fluctuations associated with oral glucocorticoid therapy and/or chronic stress, and informing the neurobiology of neuropsychiatric conditions marked by abnormal cortisol dynamics (e.g., major depression, Alzheimer's disease).

High prolactin levels are associated with more delirium in septic patients

PURPOSES

We investigated whether high prolactin levels were associated with delirium in septic patients because neuropsychiatric disorders are frequently associated with hyperprolactinemia.

MATERIALS AND METHODS

Prolactin levels were measured daily for 4 days in 101 patients with sepsis. Delirium was assessed using the Richmond Agitation Sedation Scale and the Confusion Assessment Method in the ICU.

RESULTS

Delirium developed in 79 patients (78%) and was more common in patients older than 65 years. Prolactin levels were higher in patients with delirium than in those without over the 4 days of observation (P = .032). In patients with delirium, higher prolactin levels were associated with a lower incidence of nosocomial infection (P = .006). Multivariable logistic regression showed that the Sequential Organ Failure Assessment score at intensive care unit admission (odds ratio, 1.24; 95% confidence interval, 1.04-1.48; P = .002) and the combined effect of prolactin levels with age (odds ratio, 1.018; 95% confidence interval, 1.01-1.031; P = .006) were associated with the development of delirium.

CONCLUSIONS

High prolactin levels may be a risk factor for delirium in septic patients.

Mild cognitive deficits in patients with primary adrenal insufficiency

BACKGROUND

The brain is a major target organ for cortisol considering its high density of glucocorticoid receptors. Several states of hypothalamus-pituitary-adrenal dysregulation point towards impairments in cognitive functioning. However, there is a very limited body of research on the effects of hypocortisolism on cognitive functioning.

AIM

To evaluate cognitive functioning in patients with hypocortisolism (i.e., primary adrenal insufficiency (PAI)) and to examine the possible effect of postponing early-morning hydrocortisone intake on cognitive functioning.

METHODS

Thirty-one patients with PAI on regular morning hydrocortisone intake and 31 healthy matched controls underwent nine neuropsychological tests, evaluating memory and executive functioning. In addition, the effect of normal timing and postponement of morning hydrocortisone intake on neuropsychological tests were assessed in an additional 29 patients with PAI.

RESULTS

Compared to controls, patients with PAI performed worse on auditory and visual memory tasks (all P ≤ 0.024) and executive functioning tasks (all P ≤ 0.012). In contrast, patients performed better on a concentration and an attention task (both P<0.05). Postponement of hydrocortisone intake in the morning did not affect the outcomes of neuropsychological tests.

CONCLUSION

Patients on long-term hydrocortisone replacement for PAI show mild cognitive deficits compared to controls. There was no effect of postponement of regular hydrocortisone intake on cognition.

Cardiovascular risk and white matter lesions after endocrine control of Cushing's syndrome

OBJECTIVE

Cushing's syndrome (CS) is associated with high cardiovascular risk. White matter lesions (WML) are common on brain magnetic resonance imaging (MRI) in patients with increased cardiovascular risk.

AIM

To investigate the relationship between cardiovascular risk, WML, neuropsychological performance and brain volume in CS.

DESIGN/METHODS

Thirty-eight patients with CS (23 in remission, 15 active) and 38 controls sex-, age- and education-level matched underwent a neuropsychological and clinical evaluation, blood and urine tests and 3Tesla brain MRI. WML were analysed with the Scheltens scale. Ten-year cardiovascular risk (10CVR) and vascular age (VA) were calculated according to an algorithm based on the Framingham heart study.

RESULTS

Patients in remission had a higher degree of WML than controls and active patients (P<0.001 and P=0.008 respectively), which did not correlate with cognitive performance in any group. WML severity positively correlated with diastolic blood pressure (r=0.659, P=0.001) and duration of hypertension (r=0.478, P=0.021) in patients in remission. Both patient groups (active and in remission) had higher 10CVR (P=0.030, P=0.041) and VA than controls (P=0.013, P=0.039). Neither the 10CVR nor the VA correlated with WML, although both negatively correlated with cognitive function and brain volume in patients in remission (P<0.05). Total brain volume and grey matter volume in both CS patient groups were reduced compared to controls (total volume: active P=0.006, in remission P=0.012; grey matter: active P=0.001, in remission P=0.003), with no differences in white matter volume between groups.

CONCLUSIONS

Patients in remission of Cushing's syndrome (but not active patients) have more severe white matter lesions than controls, positively correlated with diastolic pressure and duration of hypertension. Ten-year cardiovascular risk and vascular age appear to be negatively correlated with the cognitive function and brain volume in patients in remission of Cushing's syndrome.

Hypothalamic-pituitary-adrenal (HPA) axis and aging

Human aging is associated with increasing frailty and morbidity which can result in significant disability. Dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis may contribute to aging-related diseases like depression, cognitive deficits, and Alzheimer's disease in some older individuals. In addition to neuro-cognitive dysfunction, it has also been associated with declining physical performance possibly due to sarcopenia. This article reviews the pathophysiology of HPA dysfunction with respect to increased basal adrenocorticotropic hormone (ACTH) and cortisol secretion, decreased glucocorticoid (GC) negative feedback at the level of the paraventricular nucleus (PVN) of the hypothalamus, hippocampus (HC), and prefrontal cortex (PFC), and flattening of diurnal pattern of cortisol release. It is possible that the increased cortisol secretion is secondary to peripheral conversion from cortisone. There is a decline in pregnolone secretion and C-19 steroids (DHEA) with aging. There is a small decrease in aldosterone with aging, but a subset of the older population have a genetic predisposition to develop hyperaldosteronism due to the increased ACTH stimulation. The understanding of the HPA axis and aging remains a complex area with conflicting studies leading to controversial interpretations.

MECHANISMS IN ENDOCRINOLOGY: Cushing's syndrome causes irreversible effects on the human brain: a systematic review of structural and functional magnetic resonance imaging studies

BACKGROUND

Cushing's syndrome (CS) is characterized by excessive exposure to cortisol, and is associated with both metabolic and behavioral abnormalities. Symptoms improve substantially after biochemical cure, but may persist during long-term remission. The causes for persistent morbidity are probably multi-factorial, including a profound effect of cortisol excess on the brain, a major target area for glucocorticoids.

OBJECTIVE

To review publications evaluating brain characteristics in patients with CS using magnetic resonance imaging (MRI).

METHODS

Systematic review of literature published in PubMed, Embase, Web of Knowledge, and Cochrane databases.

RESULTS

Nineteen studies using MRI in patients with CS were selected, including studies in patients with active disease, patients in long-term remission, and longitudinal studies, covering a total of 339 unique patients. Patients with active disease showed smaller hippocampal volumes, enlarged ventricles, and cerebral atrophy as well as alterations in neurochemical concentrations and functional activity. After abrogation of cortisol excess, the reversibility of structural and neurochemical alterations was incomplete after long-term remission. MRI findings were related to clinical characteristics (i.e., cortisol levels, duration of exposure to hypercortisolism, current age, age at diagnosis, and triglyceride levels) and behavioral outcome (i.e., cognitive and emotional functioning, mood, and quality of life).

CONCLUSION

Patients with active CS demonstrate brain abnormalities, which only partly recover after biochemical cure, because these still occur even after long-term remission. CS might be considered as a human model of nature that provides a keyhole perspective of the neurotoxic effects of exogenous glucocorticoids on the brain.

Prevention of glucocorticoid induced bone changes with beta-ecdysone

Beta-ecdysone (βEcd) is a phytoecdysteroid found in the dry roots and seeds of the asteraceae and achyranthes plants, and is reported to increase osteogenesis in vitro. Since glucocorticoid (GC) excess is associated with a decrease in bone formation, the purpose of this study was to determine if treatment with βEcd could prevent GC-induced osteoporosis. Two-month-old male Swiss-Webster mice (n=8-10/group) were randomized to either placebo or slow release prednisolone pellets (3.3mg/kg/day) and treated with vehicle control or βEcd (0.5mg/kg/day) for 21days. GC treatment inhibited age-dependent trabecular gain and cortical bone expansion and this was accompanied by a 30-50% lower bone formation rate (BFR) at both the endosteal and periosteal surfaces. Mice treated with only βEcd significantly increased bone formation on the endosteal and periosteal bone surfaces, and increased cortical bone mass were their controls to compare to GC alone. Concurrent treatment of βEcd and GC completely prevented the GC-induced reduction in BFR, trabecular bone volume and partially prevented cortical bone loss. In vitro studies determined that βEcd prevented the GC increase in autophagy of the bone marrow stromal cells as well as in whole bone. In summary, βEcd prevented GC induced changes in bone formation, bone cell viability and bone mass. Additional studies are warranted of βEcd for the treatment of GC induced bone loss.

Neuropsychiatric disorders in Cushing's syndrome

Endogenous Cushing's syndrome (CS), a rare endocrine disorder characterized by cortisol hypersecretion, is associated with psychiatric and neurocognitive disorders. Major depression, mania, anxiety, and neurocognitive impairment are the most important clinical abnormalities. Moreover, patients most often complain of impairment in quality of life, interference with family life, social, and work performance. Surprisingly, after hypercortisolism resolution, despite the improvement of the overall prevalence of psychiatric and neurocognitive disorders, the brain volume loss at least partially persists and it should be noted that some patients may still display depression, anxiety, panic disorders, and neurocognitive impairment. This brief review aimed at describing the prevalence of psychiatric and neurocognitive disorders and their characterization both during the active and remission phases of CS. The last section of this review is dedicated to quality of life, impaired during active CS and only partially resolved after resolution of hypercortisolism.

Small cerebellar cortex volume in patients with active Cushing's syndrome

OBJECTIVE

Cushing's syndrome (CS) is associated with neuropsychological deficits. As the cerebellum plays a key role in neuropsychological functions it may be affected in CS. The aim of this study was to investigate whether patients with CS have a smaller cerebellar volume than healthy controls, and to analyse whether cerebellar volume is associated with neuropsychological performance and clinical parameters.

DESIGN

A cross-sectional study was performed.

METHODS

Thirty-six CS patients (15 with active CS and 21 with CS in remission) and 36 controls matched for age, sex, and education underwent neuropsychological testing, quality of life assessment, clinical evaluation, and magnetic resonance imaging brain scan. Cerebellar volumes (white matter and cortex, bilateral) were calculated using FreeSurfer Software.

RESULTS

Patients with active CS showed smaller bilateral cerebellar cortex volumes than controls (left, P=0.035 and right, P=0.034), as well as a trend toward smaller right cerebellar cortex volumes than patients in remission CS (P=0.051). No differences were observed in the volume of cerebellar white matter between the three groups. Both right and left cerebellar cortex volumes correlated negatively with triglyceride levels (right: r=-0.358, P=0.002 and left: r=-0.317, P=0.005) and age at diagnosis (right: r=-0.433, P=0.008 and left: r=-0.457, P=0.005). Left cerebellar cortex volume also correlated positively with visual memory performance (r=0.245, P=0.038). Right cerebellar cortex volume positively correlated with quality-of-life scores (r=0.468, P=0.004).

CONCLUSIONS

The cerebellar cortex volume is smaller in active CS patients than in controls. This finding is associated with poor visual memory and quality of life and is mostly pronounced in patients with higher triglyceride levels and older age at diagnosis.

Effects of cocaine on the hypothalamic-pituitary-adrenal axis

INTRODUCTION

Cocaine hydrochloride is a psychoactive substance extracted from the leaves of plants called Erythroxylum coca. Cocaine is the second most commonly used drug in the world after cannabis; 20 % of cocaine users will become long-term cocaine-dependent patients. Different routes of administration may be recognized: smokable modality, intranasal and intravenous. Cocaine is a potent stimulant of the sympathetic nervous system and causes structural changes on the brain, heart, lung, liver and kidney. It has long been known that use of cocaine may produce alterations to the endocrine system. Research on behavioral and neuroendocrine effects of cocaine dates back several years ago and has increasingly focused on alterations of the hypothalamic-pituitary-adrenal (HPA) axis, which appears to be the chief target of cocaine effects.

STUDIES

Animal (mainly rats and monkeys) and human studies have clearly shown a close relation between cocaine consumption and overdrive of the HPA axis. Such activation is likely involved, though via a still undefined mechanism, in the behavioral and cardiovascular changes of drug abusers as well as in the reinforcement/relapse phenomena. Further studies of the pathophysiology of cocaine addicts will help to devise new therapeutic strategies for these patients.

Persistent Comorbidities in Cushing’s Syndrome after Endocrine Cure

It was assumed that resolution of hypercortisolism in Cushing syndrome (CS) was followed by normalization of morbidity; however, in the last decade evidence is accumulating that patients with cured CS still have increased morbidity and mortality after the biochemical control of hypercortisolism. Patients with CS have an increased cardiovascular and metabolic risk and persistent accumulation of central fat, with an unfavorable adipokine profile, not only during the active phase of the disease but also long after biochemical remission. Clinical management should be particularly careful in identifying global cardiovascular risk, as a primary goal during the followup of these patients, aimed at improving global vascular morbidity. Moreover bone mass is reduced not only due to the endogenous hypercortisolism but also due to duration and dose of exogenous glucocorticoid (GC) replacement therapy after surgery. Thus, therapy in operated patients with inhibition of the hypothalamic-pituitary-adrenal axis should be reduced to the lowest dose and duration possible. Specific treatments should be considered in patients with decreased bone mass, aimed at reducing the increased fracture incidence. Finally, cognitive and health related quality of life impairments, described in active disease, are still abnormal after endocrine cure. Thus, residual morbidity persists in cured CS, suggesting irreversibility of GC-induced phenomena, typical of chronic hypercortisolism.

Cortisol is an associated-risk factor of brain dysfunction in patients with severe sepsis and septic shock

Objectives. To investigate cortisol levels in brain dysfunction in patients with severe sepsis and septic shock. Methods. In 128 septic and sedated patients, we studied brain dysfunction including delirium and coma by the evaluation of Richmond Agitation Sedation Scale (RASS), the Confusion Method Assessment in the ICU (CAM-ICU) after sedation withdrawal and the measurement of serum S100B biomarker of brain injury. Serum cortisol and S100B were measured within 12 hours after ICU admission and daily over the next four days. Results. Brain dysfunction was observed in 50% (64/128) before but in 84% (107/128) of patients after sedation withdrawal, and was more common in the patients older than 57 years (P = 0.009). Both cortisol (P = 0.007) and S100B levels (P = 0.028) were higher in patients with than patients without brain dysfunction. Cortisol levels were associated with ICU mortality (hazard ratio = 1.17, P = 0.024). Multivariate logistic regression showed that cortisol (odds ratio (OR): 2.34, 95% CI (2.01, 3.22), P = 0.02) and the combination effect of cortisol with age (OR: 1.004, 95% CI (1.002, 1.93), P = 0.038) but not S100B were associated with brain dysfunction. Conclusions. Cortisol was an associated-risk factor of brain dysfunction in patients with severe sepsis and septic shock.

Widespread reductions of white matter integrity in patients with long-term remission of Cushing's disease

BACKGROUND

Hypercortisolism leads to various physical, psychological and cognitive symptoms, which may partly persist after the treatment of Cushing's disease. The aim of the present study was to investigate abnormalities in white matter integrity in patients with long-term remission of Cushing's disease, and their relation with psychological symptoms, cognitive impairment and clinical characteristics.

METHODS

In patients with long-term remission of Cushing's disease (n = 22) and matched healthy controls (n = 22) we examined fractional anisotropy (FA) values of white matter in a region-of-interest (ROI; bilateral cingulate cingulum, bilateral hippocampal cingulum, bilateral uncinate fasciculus and corpus callosum) and the whole brain, using 3 T diffusion tensor imaging (DTI) and a tract-based spatial statistics (TBSS) approach. Psychological and cognitive functioning were assessed with validated questionnaires and clinical severity was assessed using the Cushing's syndrome Severity Index.

RESULTS

The ROI analysis showed FA reductions in all of the hypothesized regions, with the exception of the bilateral hippocampal cingulum, in patients when compared to controls. The exploratory whole brain analysis showed multiple regions with lower FA values throughout the brain. Patients reported more apathy (p = .003) and more depressive symptoms (p < .001), whereas depression symptom severity in the patient group was negatively associated with FA in the left uncinate fasciculus (p < 0.05). Post-hoc analyses showed increased radial and mean diffusivity in the patient group.

CONCLUSION

Patients with a history of endogenous hypercortisolism in present remission show widespread changes of white matter integrity in the brain, with abnormalities in the integrity of the uncinate fasciculus being related to the severity of depressive symptoms, suggesting persistent structural effects of hypercortisolism.

Telomeres and endocrine dysfunction of the adrenal and GH/IGF-1 axes

Telomeres, located at the end of linear chromosomes, are essential to maintain genomic stability. Telomere biology has recently emerged as an important player in the fields of ageing and disease. To maintain telomere length (TL) and reduce its degradation after mitosis, the telomerase enzyme complex is produced. Genetic, epigenetic, hormonal and environmental factors can regulate telomerase function. These include stress hormones such as cortisol and growth factors. The hypothalamic-pituitary-adrenal (HPA) axis has been evaluated in psychiatric diseases where hypercortisolism and oxidative stress are often present. Some researches have linked TL shortening to increases in stress-related cortisol, but others have not. The effects of cortisol on the telomere system are complex and may depend on the intensity and duration of exposure. On the other hand, low levels of IGF-1 are associated with inflammation and ageing-related diseases (ischaemic heart disease, congestive heart failure). Both IGF-1 and TL diminish with age and are positively and strongly correlated with each other. It is not clear whether this positive correlation reflects a single association or a cause-effect relationship. Further research will ideally investigate longitudinal changes in telomeres and both these hormonal axes. To our knowledge, TL dysfunction has not been described in either endogenous hypercortisolism (Cushing's syndrome) or acromegaly where excessive amounts of GH and consequently IGF-1 are produced. This review focuses on the possible relationships between telomere dysfunction and the hypothalamic-pituitary-adrenal (HPA) axis and GH-IGF-1 system.

Neuropsychiatric findings in Cushing syndrome and exogenous glucocorticoid administration

This article reviews the neuropsychiatric presentations elicited by spontaneous hypercortisolism and exogenous supraphysiologic glucocorticoids. Patients with Cushing disease and syndrome develop a depressive syndrome: irritable and depressed mood, decreased libido, disrupted sleep and cognitive decrements. Exogenous short-term glucocorticoid administration may elicit a hypomanic syndrome with mood, sleep and cognitive disruptions. Treatment options are discussed. Brain imaging and neuropsychological studies indicate elevated cortisol and other glucocorticoids are especially deleterious to hippocampus and frontal lobe. The research findings also shed light on neuropsychiatric abnormalities in conditions that have substantial subgroups exhibiting elevated and dysregulated cortisol: aging, major depressive disorder and Alzheimer's disease.

[Telomeres, aging and Cushing's syndrome: are they related?]

Cushing's syndrome is due to excess cortisol secretion and is associated to increased mortality and severe morbidity that are not fully reversible despite biochemical control. The syndrome consists of a set of systemic manifestations similar to those found in aging. Chronic stress, which also causes hyperstimulation of the hypothalamic-pituitary-adrenal axis, has been related to accelerated telomere shortening, oxidative damage, and cell aging. Although premature aging in patients with Cushing's syndrome could be related to environmental factors, the possibility that chronic exposure to hypercortisolism causes telomere shortening, and thus premature aging, cannot be ruled out. This review discusses the available evidence supporting a link between Cushing's syndrome and cell aging.

Clinical consequences of Cushing's syndrome

Recent evidence suggests that correction of hypercortisolism in Cushing's syndrome (CS) may not lead to complete remission of the clinical abnormalities associated with this condition. In particular, elevated cardiovascular risk may persist in "cured" CS patients long-term after eucortisolism has been reached. This is believed to be related with the maintenance of visceral obesity and altered adipokine secretory pattern which perpetuate features of metabolic syndrome, including impaired glucose tolerance, hypertension, dyslipidemia, atherosclerosis and hypercoagulability. Nephrolithiasis and incomplete recovery of bone mineral density have also been described in "cured" CS patients. Moreover, previous exposure to excess cortisol may have irreversible effects on the structures of the central nervous system controlling cognitive function and mood. Thus, sustained deterioration of the cardiovascular system, bone remodelling and cognitive function may be associated with high morbidity and poor quality of life in CS patients in remission for many years. Although mortality in "cured" CS patients may not differ from that in the general population, data beyond 20 years follow-up are very scarce, so further studies evaluating larger cohorts for longer follow-up periods are needed to draw definitive conclusions on longevity. Life-long monitoring is mandatory in CS patients in order to control long term complications of previous cortisol excess and, possibly, normalize life expectancy.

Chronic non-invasive corticosterone administration abolishes the diurnal pattern of tph2 expression

Both hypothalamic-pituitary-adrenal (HPA) axis activity and serotonergic systems are commonly dysregulated in stress-related psychiatric disorders. We describe here a non-invasive rat model for hypercortisolism, as observed in major depression, and its effects on physiology, behavior, and the expression of tph2, the gene encoding tryptophan hydroxylase 2, the rate-limiting enzyme for brain serotonin (5-hydroxytryptamine; 5-HT) synthesis. We delivered corticosterone (40 μg/ml, 100 μg/ml or 400 μg/ml) or vehicle to adrenal-intact adult, male rats via the drinking water for 3 weeks. On days 15, 16, 17 and 18, respectively, the rats' emotionality was assessed in the open-field (OF), social interaction (SI), elevated plus-maze (EPM), and forced swim tests (FST). On day 21, half of the rats in each group were killed 2h into the dark phase of a 12/12 h reversed light/dark cycle; the other half were killed 2h into the light phase. We then measured indices of HPA axis activity, plasma glucose and interleukin-6 (IL-6) availability, and neuronal tph2 expression at each time point. Chronic corticosterone intake was sufficient to cause increased anxiety- and depressive-like behavior in a dose-dependent manner. It also disrupted the diurnal pattern of plasma adrenocorticotropin (ACTH), corticosterone, and glucose concentrations, caused adrenal atrophy, and prevented regular weight gain. No diurnal or treatment-dependent changes were found for plasma concentrations of IL-6. Remarkably, all doses of corticosterone treatment abolished the diurnal variation of tph2 mRNA expression in the brainstem dorsal raphe nucleus (DR) by elevating the gene's expression during the animals' inactive (light) phase. Our data demonstrate that chronic elevation of corticosterone creates a vulnerability to a depression-like syndrome that is associated with increased tph2 expression, similar to that observed in depressed patients.

Advances in the epidemiology, pathogenesis, and management of Cushing's syndrome complications

Cushing's syndrome (CS) is a clinical condition resulting from chronic exposure to glucocorticoid excess. As a consequence, hypercortisolism contributes significantly to the early development of systemic disorders by direct and/or indirect effects. Complications such as obesity, hypertension, diabetes, dyslipidemia, and hypercoagulability cause premature atherosclerosis and increase cardiovascular mortality. Impairment of the skeletal system is a relevant cause of morbidity and disability in these patients especially due to the high prevalence of vertebral fractures. In addition, muscle weakness, emotional lability, depression, and impairment of quality of life are very common. Clinical management of these patients is complex and should be particularly careful in identifying global cardiovascular risks and aim at controlling all complications. Although the primary goal in the prevention and treatment of complications is the correction of hypercortisolism, treatment does not completely eliminate these comorbidities. Given that cardiovascular risk and fracture risk can persist after cure, early detection of each morbidity could prevent the development of irreversible damage. In this review we present the various complications of CS and their pathogenetic mechanisms. We also suggest the clinical management of these patients based on our extensive clinical experience and on the available literature.

Verbal and visual memory performance and hippocampal volumes, measured by 3-Tesla magnetic resonance imaging, in patients with Cushing's syndrome

CONTEXT

Cushing's syndrome (CS) affects cognition and memory.

OBJECTIVE

Our objective was to evaluate memory and hippocampal volumes (HV) on 3-tesla magnetic resonance imaging (3T MRI) in CS patients and controls.

PATIENTS AND METHODS

Thirty-three CS patients (11 active, 22 cured) and 34 controls matched for age, sex, and education underwent Rey Auditory Verbal Learning Test and Rey-Osterrieth Complex Figure memory tests. Gray matter and HV were calculated on 3T MRI, using FreeSurfer image analyses software.

RESULTS

No differences in HV were observed between active and cured CS or controls. Memory performance was worse in CS patients than controls (P < 0.04 in active; P < 0.03 in cured CS) but did not differ among CS groups, which were therefore analyzed together; they performed worse for verbal (P = 0.02) and visual memory (P = 0.04) than controls. In 12 CS patients, memory was below normative cutoff values for verbal (n = 6, cured), visual memory (n = 10, six cured) or both (n = 4); these patients with severe memory impairments showed smaller HV compared with their matched controls (P = 0.02 with verbal impairment; P = 0.03 with visual impairment). They were older (P = 0.04), had shorter education (P = 0.02), and showed a trend toward longer duration of hypercortisolism (P = 0.07) than the remaining CS patients. Total (P = 0.004) and cortical (P = 0.03) brain gray matter volumes were decreased in CS compared with controls, indicating brain atrophy, whereas subcortical gray matter (which includes HV) was reduced only in the 12 patients with severe memory impairment.

CONCLUSION

Verbal and visual memory is worse in CS patients than controls, even after biochemical cure. HV was decreased only in those whose memory scores were below normative cutoff values.

Distinct signature of altered homeostasis in aging rod photoreceptors: implications for retinal diseases

Background

Advanced age contributes to clinical manifestations of many retinopathies and represents a major risk factor for age-related macular degeneration, a leading cause of visual impairment and blindness in the elderly. Rod photoreceptors are especially vulnerable to genetic defects and changes in microenvironment, and are among the first neurons to die in normal aging and in many retinal degenerative diseases. The molecular mechanisms underlying rod photoreceptor vulnerability and potential biomarkers of the aging process in this highly specialized cell type are unknown.

Methodology/Principal Findings

To discover aging-associated adaptations that may influence rod function, we have generated gene expression profiles of purified rod photoreceptors from mouse retina at young adult to early stages of aging (1.5, 5, and 12 month old mice). We identified 375 genes that showed differential expression in rods from 5 and 12 month old mouse retina compared to that of 1.5 month old retina. Quantitative RT-PCR experiments validated expression change for a majority of the 25 genes that were examined. Macroanalysis of differentially expressed genes using gene class testing and protein interaction networks revealed overrepresentation of cellular pathways that are potentially photoreceptor-specific (angiogenesis and lipid/retinoid metabolism), in addition to age-related pathways previously described in several tissue types (oxidative phosphorylation, stress and immune response).

Conclusions/Significance

Our study suggests a progressive shift in cellular homeostasis that may underlie aging-associated functional decline in rod photoreceptors and contribute to a more permissive state for pathological processes involved in retinal diseases.

Subtle cognitive impairments in patients with long-term cure of Cushing's disease

CONTEXT AND OBJECTIVE

Active Cushing's disease is associated with cognitive impairments. We hypothesized that previous hypercortisolism in patients with Cushing's disease results in irreversible impairments in cognitive functioning. Therefore, our aim was to assess cognitive functioning after long-term cure of Cushing's disease.

DESIGN

Cognitive assessment consisted of 11 tests, which evaluated global cognitive functioning, memory, and executive functioning.

PATIENTS AND CONTROL SUBJECTS

We included 74 patients cured of Cushing's disease and 74 controls matched for age, gender, and education. Furthermore, we included 54 patients previously treated for nonfunctioning pituitary macroadenomas (NFMA) and 54 controls matched for age, gender, and education.

RESULTS

Compared with NFMA patients, patients cured from Cushing's disease had lower scores on the Mini Mental State Examination (P = 0.001), and on the memory quotient of the Wechsler Memory Scale (P = 0.050). Furthermore, patients cured from Cushing's disease tended to recall fewer words on the imprinting (P = 0.013), immediate recall (P = 0.012), and delayed recall (P = 0.003) trials of the Verbal Learning Test of Rey. On the Rey Complex Figure Test, patients cured from Cushing's disease had lower scores on both trials (P = 0.002 and P = 0.007) compared with NFMA patients. Patients cured from Cushing's disease also made fewer correct substitutions on the Letter-Digit Substitution Test (P = 0.039) and came up with fewer correct patterns on the Figure Fluency Test (P = 0.003) compared with treated NFMA patients.

CONCLUSIONS

Cognitive function, reflecting memory and executive functions, is impaired in patients despite long-term cure of Cushing's disease. These observations indicate irreversible effects of previous hypercortisolism on cognitive function and, thus, on the central nervous system. These observations may also be of relevance for patients treated with high-dose exogenous glucocorticoids.