Hypercortisolism is associated with increased coronary arterial atherosclerosis: analysis of noninvasive coronary angiography using multidetector computerized tomography

Cortisol as a marker for increased mortality in patients with incidental adrenocortical adenomas

CONTEXT

Incidental benign adrenocortical adenomas, adrenal incidentalomas are found in 4.5% of abdominal computed tomography scans, with the incidence increasing to 10% in patients older than 70 years of age. These incidentalomas frequently show evidence of excess cortisol secretion but without overt Cushing's syndrome. The mortality rate is increased in Cushing's syndrome.

OBJECTIVE

This study sought to investigate whether patients with adrenal incidentalomas have an increased mortality.

DESIGN

This was a retrospective, longitudinal cohort study.

SETTING

The study was carried out in an Endocrine Investigation Unit in a University Teaching Hospital.

PATIENTS

Two hundred seventy-two consecutive patients with an incidental adrenal mass underwent a dedicated diagnostic protocol, which included dexamethasone testing for hypercortisolism between 2005 and 2013. Overall survival was assessed in 206 patients with a benign, adrenocortical adenoma.

MAIN OUTCOME MEASURES

Survival analysis was carried out by using Kaplan-Meier curves and the effect of dexamethasone cortisol estimated by Cox-regression analysis. Cause-specific mortality was ascertained from death certificates and compared with local and national data.

RESULTS

Eighteen of 206 patients died and the mean time (SD) from diagnosis to death was 3.2 (1.7) years. Seventeen of 18 patients who died had a post dexamethasone cortisol >1.8 μg/dL and there was a significant decrease in survival rate with increasing dexamethasone cortisol levels (P = .001). Compared with the <1.8 μg/dL group, the hazard ratio (95% confidence interval) for the 1.8-5 μg/dL group was 12.0 (1.6-92.6) whereas that of the >5 μg/dL group was 22.0 (2.6-188.3). Fifty percent and 33% of deaths were secondary to circulatory or respiratory/infective causes, respectively.

CONCLUSIONS

PATIENTS with adrenal incidentalomas and a post-dexamethasone serum cortisol >1.8 μg/dL have increased mortality, mainly related to cardiovascular disease and infection.

Cardiac structure and function in Cushing's syndrome: a cardiac magnetic resonance imaging study

BACKGROUND

Patients with Cushing's syndrome have left ventricular (LV) hypertrophy and dysfunction on echocardiography, but echo-based measurements may have limited accuracy in obese patients. No data are available on right ventricular (RV) and left atrial (LA) size and function in these patients.

OBJECTIVES

The objective of the study was to evaluate LV, RV, and LA structure and function in patients with Cushing's syndrome by means of cardiac magnetic resonance, currently the reference modality in assessment of cardiac geometry and function.

METHODS

Eighteen patients with active Cushing's syndrome and 18 volunteers matched for age, sex, and body mass index were studied by cardiac magnetic resonance. The imaging was repeated in the patients 6 months (range 2-12 mo) after the treatment of hypercortisolism.

RESULTS

Compared with controls, patients with Cushing's syndrome had lower LV, RV, and LA ejection fractions (P < .001 for all) and increased end-diastolic LV segmental thickness (P < .001). Treatment of hypercortisolism was associated with an improvement in ventricular and atrial systolic performance, as reflected by a 15% increase in the LV ejection fraction (P = .029), a 45% increase in the LA ejection fraction (P < .001), and an 11% increase in the RV ejection fraction (P = NS). After treatment, the LV mass index and end-diastolic LV mass to volume ratio decreased by 17% (P < .001) and 10% (P = .002), respectively. None of the patients had late gadolinium myocardial enhancement.

CONCLUSION

Cushing's syndrome is associated with subclinical biventricular and LA systolic dysfunctions that are reversible after treatment. Despite skeletal muscle atrophy, Cushing's syndrome patients have an increased LV mass, reversible upon correction of hypercortisolism.

Impairment of Arterial Compliance in Cushing's Syndrome

Arterial stiffness may be useful for stratifying cardiovascular risk in individuals suffering from a number of pathologies, such as hypertension, diabetes, obesity, dyslipidaemia and coronary artery disease. Cushing's syndrome is underpinned by a complex metabolic syndrome, which is potentially implicated in the onset of blood vessel alterations and the increase in arterial wall stiffness. The aim of this paper was to perform a review about the most important studies conducted in order to evaluate the arterial distensibility profile of subjects affected by Cushing's syndrome. Increased arterial stiffness may persist even after successful cure of this disease. It is therefore of fundamental importance to identify the presence of early vascular alterations in these patients, in order to commence their treatment and thus attempt to prevent the subsequent onset of adverse cardiovascular events.

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.

Cardio-metabolic consequences of glucocorticoid replacement: relevance of ultradian signalling

Chronic exposure to elevated glucocorticoid levels is associated with obesity, insulin resistance, impaired glucose tolerance, hypertension and dyslipidaemia, manifest classically in Cushing's syndrome and with high-dose glucocorticoid therapy. However, cardiovascular events are also reportedly higher in patients with primary and secondary hypoadrenalism receiving 'replacement' glucocorticoid doses. This has been attributed to an inability to mimic accurately the diurnal rhythm of cortisol with current oral replacement therapy and subsequent glucocorticoid excess. Although development of delayed release oral preparations has sought to overcome this problem, there has been little attention on the ultradian rhythm of glucocorticoids and its relevance for replacement therapy and associated cardio-metabolic comorbidity. Endogenous glucocorticoids are released in a pulsatile manner, and this ultradian rhythm is important in maintaining homeostatic control through glucocorticoid-receptor (GR)-dependent transcription regulation that rapidly responds to circulating hormone levels. Constant glucocorticoid exposure can result in continuous transcription, aberrant mRNA accumulation and abnormal protein levels. GR regulation of transcription programmes is highly cell and tissue specific, binding to distinct genomic loci in different cellular contexts. GR also interacts with a large cohort of DNA-binding factors with cell-specific interactions. The relevance of kinetic patterns of GR-dependent gene expression in vivo is not yet fully elucidated. However, given that GR gene variants are associated with cardiovascular disease, it is possible that ultradian delivery of glucocorticoid replacement may become important, at least in selected patients.

Correlations of vascular architecture and angiogenesis with pituitary adenoma histotype

Vascular endothelial growth factor (VEGF) is a potent angiogenic factor in solid tumors. However, its role in angiogenesis in pituitary adenoma is controversial. Angiogenesis in solid tumors including pituitary adenoma is commonly evaluated by microvascular density (MVD). Here, we evaluated MVD and the role of VEGF in vascular architecture in 51 pituitary adenomas (24 nonfunctioning, 13 prolactin-secreting, 10 growth hormone-secreting, 3 adrenocorticotropic hormone-secreting, and 1 thyroid-stimulating hormone-secreting). Paraffin sections were stained with CD34 and VEGF. MVD and vascular architecture parameters (vessel area, diameter, perimeter, and roundness) were evaluated in CD34-stained sections. Immunohistochemistry showed 27/51 tumors (53%) were VEGF-positive. There were no significant differences in MVD, any vascular parameter, or adenoma volume between VEGF-positive and VEGF-negative tumors. VEGF mRNA expression was significantly higher in VEGF-positive tumors. There were no significant correlations between VEGF mRNA expression and MVD or vascular parameters. However, vessel diameter and perimeter were significantly larger in prolactin-secreting than nonfunctioning and growth hormone-secreting macroadenomas. The difference in vessel diameter was observed among both VEGF-positive and all adenomas (micro- and macroadenoma). Thus, VEGF may have limited roles in the development of vascular architecture and tumor angiogenesis in pituitary adenomas, but the differences in vessel architecture by histotype (i.e., larger vessel diameter and perimeter in prolactin-secreting adenomas) suggest the hormonal regulation of vessel architecture rather than angiogenesis.