The aging-liked alterations in Cushing's disease: A neurite orientation dispersion and density imaging (NODDI) study

Analysis of brain structural covariance network in Cushing disease

Background

Cushing disease (CD) is a rare clinical neuroendocrine disease. CD is characterized by abnormal hypercortisolism induced by a pituitary adenoma with the secretion of adrenocorticotropic hormone. Individuals with CD usually exhibit atrophy of gray matter volume. However, little is known about the alterations in topographical organization of individuals with CD. This study aimed to investigate the structural covariance networks of individuals with CD based on the gray matter volume using graph theory analysis.

Methods

High-resolution T1-weighted images of 61 individuals with CD and 53 healthy controls were obtained. Gray matter volume was estimated and the structural covariance network was analyzed using graph theory. Network properties such as hubs of all participants were calculated based on degree centrality.

Results

No significant differences were observed between individuals with CD and healthy controls in terms of age, gender, and education level. The small-world features were conserved in individuals with CD but were higher than those in healthy controls. The individuals with CD showed higher global efficiency and modularity, suggesting higher integration and segregation as compared to healthy controls. The hub nodes of the individuals with CD were Short insular gyri (G_insular_short_L), Anterior part of the cingulate gyrus and sulcus (G_and_S_cingul-Ant_R), and Superior frontal gyrus (G_front_sup_R).

Conclusions

Significant differences in the structural covariance network of patients with CD were found based on graph theory. These findings might help understanding the pathogenesis of individuals with CD and provide insight into the pathogenesis of this CD.

Long-Term Consequences of Cushing Syndrome: A Systematic Literature Review

It is held that the condition of endogenous chronic hypersecretion of cortisol (Cushing syndrome, CS), causes several comorbidities, including cardiovascular and metabolic disorders, musculoskeletal alterations, as well as cognitive and mood impairment. Therefore, CS has an adverse impact on the quality of life and life expectancy of affected patients. What remains unclear is whether disease remission may induce a normalization of the associated comorbid conditions. In order to retrieve updated information on this issue, we conducted a systematic search using the Pubmed and Embase databases to identify scientific papers published from January 1, 2000, to December 31, 2022. The initial search identified 1907 potentially eligible records. Papers were screened for eligibility and a total of 79 were included and classified by the main topic (cardiometabolic risk, thromboembolic disease, bone impairment, muscle damage, mood disturbances and quality of life, cognitive impairment, and mortality). Although the limited patient numbers in many studies preclude definitive conclusions, most recent evidence supports the persistence of increased morbidity and mortality even after long-term remission. It is conceivable that the degree of normalization of the associated comorbid conditions depends on individual factors and characteristics of the conditions. These findings highlight the need for early recognition and effective management of patients with CS, which should include active treatment of the related comorbid conditions. In addition, it is important to maintain a surveillance strategy in all patients with CS, even many years after disease remission, and to actively pursue specific treatment of comorbid conditions beyond cortisol normalization.

Irreversible Alterations of Susceptibility in Cushing's Disease: A Longitudinal QSM Study

OBJECTIVES

Chronic exposure to hypercortisolism is associated with accelerated aging and neurodegenerative diseases, while Cushing's disease (CD) is the most common form of endogenous hypercortisolism exposure. This study aimed to assess longitudinal susceptibility changes in CD using quantitative susceptibility mapping (QSM) before and after resolution of hypercortisolism.

METHODS

In this study, twenty-four CD patients and 24 healthy controls underwent magnetic resonance imaging with QSM. All CD patients underwent MRI scans before and after the curative operation.

RESULTS

After resolution of hypercortisolism, irreversibly altered susceptibility values were found in the anterior cingulate cortex, frontal lobe, caudate and red nucleus. These alterations were significantly correlated with the changes in gray matter/white matter volumes and clinical features. Additionally, decrease susceptibility was found in several regions in CD patients.

CONCLUSION

Chronic exposure to hypercortisolism may be related to susceptibility alterations and significantly correlated with altered brain volumes and clinical features. in CD patients. The decrease of susceptibility might suggest the involvement of the calcium deregulation in these alterations.

Structural and functional brain alterations in Cushing's disease: A narrative review

Neurocognitive and psychiatric symptoms are non-negligible in Cushing's disease and are accompanied by structural and functional alterations of the brain. In this review, we have summarized multimodal neuroimaging and neurophysiological studies to highlight the current and historical understandings of the structural and functional brain alterations in Cushing's disease. Specifically, structural studies showed atrophy of the gray matter, loss of white matter integrity, and demyelination in widespread brain regions. Functional imaging studies have identified three major functional brain connectome networks influenced by hypercortisolemia: the limbic network, the default mode network, and the executive control network. After endocrinological remission, atrophy of gray matter regions and the compromised functional network activities were partially reversible, and the widespread white matter integrity alterations cannot recover in years. In conclusion, Cushing's disease patients display structural and functional brain connectomic alterations, which provides insights into the neurocognitive and psychiatric symptoms observed in this disease.