The estimation of selected endogenous anticoagulation system parameters in patients with subclinical Cushing's syndrome

Daytime plasma cortisol and cortisol response to dexamethasone suppression are associated with a prothrombotic state in hypertension

Background and aims

A prothrombotic state was demonstrated in patients with Cushing's syndrome and is involved in the development and progression of cardiovascular and renal damage in hypertensive patients. This study was designed to examine the relationships between cortisol secretion and the hemostatic and fibrinolytic systems in hypertension.

Methods

In 149 middle-aged, nondiabetic, essential hypertensive patients free of cardiovascular and renal complications, we measured hemostatic markers that express the spontaneous activation of the coagulation and fibrinolytic systems and assessed daily cortisol levels (8 AM, 3 PM, 12 AM; area under the curve, AUC-cortisol) together with the cortisol response to dexamethasone overnight suppression (DST-cortisol).

Results

Plasma levels of D-dimer (D-dim), prothrombin fragment 1 + 2 (F1 + 2), and von Willebrand factor (vWF) were progressively and significantly higher across tertiles of AUC-cortisol and DST-cortisol, whereas no differences were observed in fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor-1, antithrombin III, protein C, and protein S. D-dim, F1 + 2, and vWF were significantly and directly correlated with age and both AUC-cortisol and DST-cortisol. Multivariate regression analysis showed that both AUC-cortisol and DST-cortisol were related to plasma D-dim, F1 + 2, and vWF independently of age, body mass index, blood pressure, and renal function.

Conclusion

Greater daily cortisol profile and cortisol response to overnight suppression are independently associated with a prothrombotic state in hypertensive patients and might contribute to the development of organ damage and higher risk of cardiovascular complications.

Pathophysiology of Mild Hypercortisolism: From the Bench to the Bedside

Mild hypercortisolism is defined as biochemical evidence of abnormal cortisol secretion without the classical detectable manifestations of overt Cushing’s syndrome and, above all, lacking catabolic characteristics such as central muscle weakness, adipose tissue redistribution, skin fragility and unusual infections. Mild hypercortisolism is frequently discovered in patients with adrenal incidentalomas, with a prevalence ranging between 5 and 50%. This high variability is mainly due to the different criteria used for defining this condition. This subtle cortisol excess has also been described in patients with incidentally discovered pituitary tumors with an estimated prevalence of 5%. To date, the mechanisms responsible for the pathogenesis of mild hypercortisolism of pituitary origin are still not well clarified. At variance, recent advances have been made in understanding the genetic background of bilateral and unilateral adrenal adenomas causing mild hypercortisolism. Some recent data suggest that the clinical effects of glucocorticoid (GC) exposure on peripheral tissues are determined not only by the amount of the adrenal GC production but also by the peripheral GC metabolism and by the GC sensitivity. Indeed, in subjects with normal cortisol secretion, the combined estimate of cortisol secretion, cortisone-to-cortisol peripheral activation by the 11 beta-hydroxysteroid dehydrogenase enzyme and GC receptor sensitizing variants have been suggested to be associated with the presence of hypertension, diabetes and bone fragility, which are three well-known consequences of hypercortisolism. This review focuses on the pathophysiologic mechanism underlying both the different sources of mild hypercortisolism and their clinical consequences (bone fragility, arterial hypertension, subclinical atherosclerosis, cardiovascular remodeling, dyslipidemia, glucose metabolism impairment, visceral adiposity, infections, muscle damage, mood disorders and coagulation).

Effect of Glucocorticoid Administration in Intravenous Pulses on Selected Parameters of the Coagulation System

BACKGROUND

Changes of the coagulation system are promoted by serious infectious or noninfectious diseases, surgical procedures, and exogenous substances, including drugs. This study aimed to assess the effect of methylprednisolone pulses on selected parameters of the coagulation system.

METHODS

The study group consisted of patients suffering from multiple sclerosis, thyroid orbitopathy, or sudden sensorineural hearing loss. 48 patients and 20 healthy volunteers were examined. The hemostatic parameters: activity of coagulation factors (VIII, IX, and XI), antithrombin activity, protein C and S activity, and concentration of soluble tissue factor were analyzed at baseline and after 3 g and 5 g of methylprednisolone administration.

RESULTS

A statistically significant increase was noted in the activity of all the studied plasma coagulation factors, plasma coagulation inhibitors (except protein S activity), and the concentration of soluble tissue factor after methylprednisolone administration.

CONCLUSION

The glucocorticoids administered in the intravenous pulses of methylprednisolone shift the balance toward thromboembolic complications.

Frequently asked questions and answers (if any) in patients with adrenal incidentaloma

PURPOSE

Adrenal incidentalomas (AIs) are incidentally discovered adrenal masses, during an imaging study undertaken for other reasons than the suspicion of adrenal disease. Their management is not a minor concern for patients and health-care related costs, since their increasing prevalence in the aging population. The exclusion of malignancy is the first question to attempt, then a careful evaluation of adrenal hormones is suggested. Surgery should be considered in case of overt secretion (primary aldosteronism, adrenal Cushing's Syndrome or pheochromocytoma), however the management of subclinical secretion is still a matter of debate.

METHODS

The aim of the present narrative review is to offer a practical guidance regarding the management of AI, by providing evidence-based answers to frequently asked questions.

CONCLUSION

The clinical experience is of utmost importance: a personalized diagnostic-therapeutic approach, based upon multidisciplinary discussion, is suggested.

Hypercoagulability in Cushing's syndrome: From arterial to venous disease

Cushing's syndrome (CS) is associated with multisystemic complications; the hematological system is not spared. Alteration in hemostatic parameters and in vivo endothelial dysfunction lead to increased thrombotic events. Arterial and venous thrombotic events carry significant morbidity and mortality. Death from cardiovascular and pulmonary embolism account for more than 50% of mortality. Surgery is a critical period; close to 50% of events occur in the 1-2 months after intervention. The evaluation and risk stratification of patients with CS is key to prevent events, balancing the risk-benefit of anticoagulation in this population. This current review will focus on up-to-date data on epidemiology, pathophysiology and management of hypercoagulability in CS.

Cardiovascular complications of mild autonomous cortisol secretion

Adrenal incidentalomas (AI) may be associated with a mild autonomous cortisol secretion (MACS) in up to one third of cases. There is growing evidence that MACS patients actually present increased risk of cardiovascular disease and higher mortality rate, driven by increased prevalence of known cardiovascular risk factors, as well as accelerated cardiovascular remodelling. Adrenalectomy seems to have cardiometabolic beneficial effects in MACS patients but their management is still a debated topic due to the lack of high-quality studies. Several studies suggested that so called "non-functioning" AI may be actually "functioning" with an associated increased cardiovascular risk. Although the individual cortisol sensitivity and peripheral activation have been recently suggested to play a role in influencing the cardiovascular risk even in apparently eucortisolemic patients, to date the degree of cortisol secretion, as mirrored by the cortisol levels after dexamethasone suppression test remains the best predictor of an increased cardiovascular risk in AI patients. However, whether or not the currently used cut-off set at 50 nmol/L for cortisol levels after dexamethasone suppression could be considered completely reliable in ruling out hypercortisolism remains unclear.

Cardiovascular mortality in patients with subclinical Cushing

Patients with adrenal incidentaloma (AI) and subclinical hypercortisolism (SH) show a high prevalence of cardiovascular risk factors and an increased prevalence and incidence of cardiovascular events. Furthermore, some recent data suggest that in these patients, the cardiovascular mortality is also increased. Unfortunately, to date, the diagnosis of SH is still a matter of debate, and, therefore, it is still not possible to address the treatment of choice (i.e. surgical or conservative approach) in many AI patients. Overall, the available data show that in AI patients with established SH the surgical removal of the adrenal mass causing SH can lead to the improvement of hypertension and diabetes, but in many patients with possible SH the effect of surgery is still largely unknown. Finally, no data are available on the effect of the recovery from SH on the cardiovascular events. Therefore, randomized studies are needed to investigate the possibility of predicting the usefulness of surgery by using the available indexes of cortisol secretion in the individual AI patient. Finally, the development of safe and well-tolerated drugs aimed to control cortisol secretion will be among the goals of the future research.

Hypercoagulability and Risk of Venous Thromboembolic Events in Endogenous Cushing's Syndrome: A Systematic Meta-Analysis

Background: Hypercortisolism has been implicated in the development of venous thromboembolic events (VTE). We aimed to characterize VTE risk in endogenous Cushing's syndrome (CS) patients, compare that risk to other pathologies, and determine if there are any associated coagulation factor changes. Methods: Medline and Scopus search for "hypercortisolism" and "thromboembolic disease" from January 1980 to April 2017 to include studies that reported VTE rates and/or coagulation profile of CS patients. A systematic review and meta-analysis were performed. Results: Forty-eight studies met inclusion criteria. There were 7,142 CS patients, average age was 42 years and 77.7% female. Odds ratio of spontaneous VTE in CS is 17.82 (95%CI 15.24-20.85, p < 0.00001) when comparing to a healthy population. For CS patients undergoing surgery, the odds ratio (both with / without anticoagulation) of spontaneous VTE is 0.26 (95%CI 0.07-0.11, p < 0.00001)/0.34 (0.19-0.36, p < 0.00001) when compared to patients undergoing hip fracture surgery who were not treated with anticoagulants. Coagulation profiles in patients with CS showed statistically significant differences compared to controls, as reflected by increases in von Willebrand factor (180.11 vs. 112.53 IU/dL, p < 0.01), as well as decreases in activated partial thromboplastin time (aPTT; 26.91 vs. 30.65, p < 0.001) and increases in factor VIII (169 vs. 137 IU/dL, p < 0.05). Conclusion: CS is associated with significantly increased VTE odds vs. general population, but lower than in patients undergoing major orthopedic surgery. Although exact timing, type, and dose of anticoagulation medication remains to be established, clinicians might consider monitoring vWF, PTT, and factor VIII when evaluating CS patients and balance advantages of thromboprophylaxis with risk of bleeding.

Hypercoagulability in patients with Cushing disease detected by thrombin generation assay is associated with increased levels of neutrophil extracellular trap-related factors

Patients with Cushing disease (CD) are at increased risk of venous thromboembolism (VTE). It was surmised, but not conclusively shown that the risk is related to plasma hypercoagulability secondary to the glucocorticoids effect. This study is aimed at detecting hypercoagulability in patients with CD. Case-control study of 48 CD patients and controls enrolled at two Italian clinics for whom we assessed the thrombin-forming-potential in the presence of optimal activation of protein C obtained by adding into the assay system its main endothelial activator, thrombomodulin. These experimental conditions mimic more closely than any other test the in vivo situation. We observed enhanced thrombin-generation in CD patients, as shown by the modification of thrombin-generation parameters [i.e., shortened lag-time and time-to-peak, increased thrombin peak and endogenous thrombin potential (ETP)]. Moreover, the ETP ratio (with/without thrombomodulin), recognized as an index of hypercoagulability, was increased in patients as compared to controls. We attempted to explain such hypercoagulability by measuring both procoagulant and anticoagulant factors, and some other non-coagulation parameters (i.e., neutrophil extracellular traps (NET), recently associated with the VTE risk and/or increased hypercoagulability. We showed that the hypercoagulability in patients with CD is associated with increased levels of factor VIII and NET-related variables. We detected plasma hypercoagulability in patients with CD and found experimental explanation for its occurrence. Whether this hypercoagulability can entirely explain the occurrence of VTE in patients with CD should be investigated by ad-hoc clinical trials. However, until these studies will be available the evidence supports the concept that patients with CD are candidates for antithrombotic prophylaxis.

Mechanisms in endocrinology: The spectrum of haemostatic abnormalities in glucocorticoid excess and defect

Glucocorticoids (GCs) target several components of the integrated system that preserves vascular integrity and free blood flow. Cohort studies on Cushing's syndrome (CS) have revealed increased thromboembolism, but the pathogenesis remains unclear. Lessons from epidemiological data and post-treatment normalisation time suggest a bimodal action with a rapid and reversible effect on coagulation factors and an indirect sustained effect on the vessel wall. The redundancy of the steps that are potentially involved requires a systematic comparison of data from patients with endogenous or exogenous hypercortisolism in the context of either inflammatory or non-inflammatory disorders. A predominant alteration in the intrinsic pathway that includes a remarkable rise in factor VIII and von Willebrand factor (vWF) levels and a reduction in activated partial thromboplastin time appears in the majority of studies on endogenous CS. There may also be a rise in platelets, thromboxane B2, thrombin-antithrombin complexes and fibrinogen (FBG) levels and, above all, impaired fibrinolytic capacity. The increased activation of coagulation inhibitors seems to be compensatory in order to counteract disseminated coagulation, but there remains a net change towards an increased risk of venous thromboembolism (VTE). Conversely, GC administered in the presence of inflammation lowers vWF and FBG, but fibrinolytic activity is also reduced. As a result, the overall risk of VTE is increased in long-term users. Finally, no studies have assessed haemostatic abnormalities in patients with Addison's disease, although these may present as a consequence of bilateral adrenal haemorrhage, especially in the presence of antiphospholipid antibodies or anticoagulant treatments. The present review aimed to provide a comprehensive overview of the complex alterations produced by GCs in order to develop better screening and prevention strategies against bleeding and thrombosis.

Perioperative thromboprophylaxis in Cushing's disease: What we did and what we are doing?

PURPOSE

Cushing's disease (CD) is associated with an increased risk of thrombotic events, particularly after surgery. No guidelines are available on the management of patients with CD undergoing pituitary transsphenoidal surgery (TSS). We aimed to compare the effectiveness of different prophylactic procedures on the prevention of thrombotic events after surgery in CD.

METHODS

We retrospectively collected data on 78 consecutive patients who underwent TSS for CD between 2001 and 2012 at Padova's Neurosurgical Unit, recording their hemostatic, hormonal and anthropometric parameters. Patients were divided into two groups according to their perioperative management. Group A (34 patients) received fractionated heparin for a maximum of 14 days after surgery. Patients in group B (44 patients) were given no early glucocorticoid replacement therapy, and treated with subcutaneous enoxaparin 4,000-8,000 U/daily (depending on their weight) for 30 days plus graduated elastic stockings until mobilization, and early ambulation.

RESULTS

The whole cohort of patients had clotting and anticoagulant factors significantly higher than the normal range. The two groups were comparable for age, BMI, ACTH, urinary free cortisol levels, outcome of surgery, and main clotting parameters. The surgical procedure did not change during the study period. Three venous thrombotic events [venous thromboembolic events (VTE), 2 associated with pulmonary embolism] were recorded in group A, none in group B (p = 0.079). No hemorrhagic events were reported.

CONCLUSIONS

Provoked thrombotic events pose a major problem in the management of CD patients after surgery, regardless of the procedure's outcome. The prophylactic regimen proposed in this paper afforded an efficacy prophylaxis against postoperative VTE in patients with CD. Due to the rarity of CD, a multicenter study on a larger sample of cases would be warranted in order to collect more thrombotic events.

Activity of selected coagulation factors in overt and subclinical hypercortisolism

It is universally acknowledged that glucocorticoids are hormones that exert a significant effect on hemostasis. The aim of this study was to analyze the activities of coagulation factors VIII, von Willebrand (vW), IX, X, and XI, in patients with overt and subclinical hypercortisolism, as well as to examine possible associations between activities of these factors and the degree of hypercortisolism. Thirty endogenous hypercortisolemic patients were included in the study. Twelve of them were diagnosed with overt Cushing's syndrome (OCS), and eighteen with subclinical Cushing's syndrome (SCS). Healthy, age- and sex-matched volunteers comprised the control group. Activities of coagulation factors VIII, IX, X, and XI were examined using a coagulometric method, and von Willebrand factor (vWF) using an immunoturbidimetric method. Mean activities of examined coagulation factors were significantly higher in OCS patients in comparison to healthy controls. SCS patients had significantly higher mean vWF activities versus controls; and a clear trend toward higher mean activities of other factors in SCS patients versus controls was recorded (but no significant differences). Furthermore, statistically significant positive correlations were found between activities of factor IX and: morning serum cortisol concentrations, 24-hour urinary cortisol excretion values, cortisol concentrations in the overnight suppression test with 1 mg of dexamethasone. Activities of factors X and XI positively correlated with cortisol levels in the overnight suppression test. In endogenous hypercortisolemic patients the coagulation pathway is hyperactivated as indicated by increased activities of coagulation factors. These disorders are evident among patients with overt hypercortisolism.

D-dimer as a significant marker of deep vein thrombosis in patients with subclinical or overt Cushing's syndrome

Venous thromboembolism (VTE) is frequently associated with hypercortisolemia. This retrospective single-center study aimed to clarify the significance of plasma D-dimer levels for VTE screening in patients with subclinical or overt Cushing's syndrome (soCS). A total of 72 consecutive treatment-naïve patients with soCS diagnosed at Kobe University Hospital between 2002 and 2014 were enrolled. Patients with both lower extremity ultrasound and D-dimer measurement data (n = 19) were recruited in study 1 and divided into 2 groups, a deep vein thrombosis (DVT) (-) group (n = 12) and DVT (+) group (n = 7) for a comparison of the associated factors. The age and D-dimer levels were higher in the DVT (+) group than in the DVT (-) group (p = 0.04 and 0.02, respectively). A receiver operating characteristic analysis found that D-dimer level ≥2.6 μg/mL correlated with the presence of DVT (sensitivity, 100%; specificity, 91.7%). Next, patients with D-dimer measurement data (n = 36) were recruited in study 2 and divided into 2 groups according to D-dimer level: D-dimer (-), <1 μg/mL group (n = 23) and D-dimer (+), ≥1 μg/mL group (n = 13); the groups were compared with respect to various VTE-related risk factors. A logistic regression analysis revealed that elevated cortisol level after low-dose dexamethasone suppression was a significant risk factor for D-dimer elevation (OR = 1.21, p = 0.02). In conclusion, these data demonstrate that a D-dimer level ≥2.6 μg/mL is an indicator of DVT in treatment naïve patients with soCS and suggests that relatively high autonomous cortisol secretion may be associated with thrombus formation.

Homocysteine and alpha-1 antitrypsin concentration in patients with subclinical hypercortisolemia

PURPOSE

Glucocorticoids have particularly strong impact on the thromboembolic complications. A factor which increases the risk of thrombosis is hyperhomocysteinemia, observed in patients with hypercortisolemia. Proinflammatory factors also affect the haemostatic balance. There has been an extensive research which estimates hemostatic system in patients with Cushing's syndrome. Undoubtedly, much fewer publications are available on thromboembolic complications in patients with Subclinical Cushing's Syndrome (SCS). The purpose of this study was to estimate of homocysteine (HCY) and alpha-1 antitrypsin (α1ATp) concentrations in patients with SCS.

MATERIALS AND METHODS

We studied 35 patients (56.0 ± 15.0 years) with SCS and 33 healthy volunteers (53.3 ± 17.7 years). In all subjects the analysis of HCY and α1ATp concentration in serum was determined with an immunonephelometric method. P-values below 0.05 were considered statistically significant.

RESULTS

A comparison of HCY and α1ATp mean concentrations in patients with SCS and healthy representatives indicated statistically higher values of both analysed parameters in the sera of patients than in the healthy controls (p values were 0.018 and 0.008, respectively). In the patients with SCS a negative correlation between α1ATp and cortisol concentration in overnight dexamethasone test was found (p=0.017, R=-0.40). We did not reveal any statistically significant correlation between the concentrations of HCY and α1ATp, and coagulation parameters such as INR, APTT, fibrinogen concentration in patients with SCS.

CONCLUSIONS

On the basis of the obtained results, a slight increase in the concentration of homocysteine and α1ATp is observed in patients with SCS, which may influence vascular complications.