Circadian blood pressure profile in patients with Cushing's syndrome before and after treatment

Diagnosis and management of hypertension in patients with Cushing's syndrome: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension

Endogenous/exogenous Cushing's syndrome is characterized by a cluster of systemic manifestations of hypercortisolism, which cause increased cardiovascular risk. Its biological basis is glucocorticoid excess, acting on various pathogenic processes inducing cardiovascular damage. Hypertension is a common feature in Cushing's syndrome and may persist after normalizing hormone excess and discontinuing steroid therapy. In endogenous Cushing's syndrome, the earlier the diagnosis the sooner management can be employed to offset the deleterious effects of excess cortisol. Such management includes combined treatments directed against the underlying cause and tailored antihypertensive drugs aimed at controlling the consequences of glucocorticoid excess. Experts on endocrine hypertension and members of the Working Group on Endocrine Hypertension of the European Society of Hypertension (ESH) prepared this Consensus document, which summarizes the current knowledge in epidemiology, genetics, diagnosis, and treatment of hypertension in Cushing's syndrome.

Impact of cortisol on blood pressure and hypertension-mediated organ damage in hypertensive patients

OBJECTIVES

Patients with overt and subclinical Cushing's syndrome frequently develop hypertension, metabolism disorders, and atherosclerotic lesions. The aim of the present study was to test the association between cortisol and blood pressure (BP), organ damage, and metabolic parameters in hypertensive patients without hypercortisolism.

METHODS

After exclusion of patients treated with corticosteroids or with Cushing's syndrome, the cohort included 623 hypertensive patients (mean ± SD age 50.3 ± 15.4 years, 50.9% men, median 24-h BP 146/88 mmHg) with an extended work-up (lipid profile, hypertension-mediated organ damage). Cortisol secretion was assessed by plasma cortisol at 0800 and 1600 h, and by 24-h urinary free cortisol (24 h UFC) normalized if required to urine creatinine (UFC/U creat).

RESULTS

Plasma cortisol at 1600 h, 24 h-UFC, and UFC/U creat were significantly and positively correlated with daytime, night-time, and 24-h SBP; plasma cortisol at 0800 h was not associated with BP. The strongest correlations were observed in the subgroup of aged more than 50 years (correlation coefficients between 0.23 and 0.28). These correlations remained after adjustment on plasma aldosterone. Metabolic parameters were weakly associated with cortisol. Arterial stiffness (central pulse pressure and pulse wave velocity), plasma NT-proBNP, and microalbuminuria were significantly correlated with 24 h UFC, UFC/U creat, and plasma cortisol at 1600 h.

CONCLUSION

Cortisol influences weakly the level of BP independently from plasma aldosterone in hypertensive patients, particularly in older patients, and that there was weak association with HMOD. It may, therefore, be of interest to test specific treatments targeting cortisol excess in selected hypertensive patients.

Remission of hypertension after surgical cure of Cushing's syndrome

CONTEXT

Hypertension associated with Cushing's syndrome (CS) increases cardiovascular risk. The time-course of improvement after cure is unclear.

OBJECTIVE

To describe the time-course and predictors of blood pressure (BP) normalization during one year after surgical cure of CS.

DESIGN

Retrospective chart review of 75 hypertensive adults cured of CS (72 with ACTH-dependent CS; 3 with adrenal adenoma). Hypertension was defined as current use of antihypertensives, a systolic BP >130 mm Hg, or diastolic BP >80 mm Hg.

MAIN OUTCOME MEASURE(S)

Remission of hypertension: BP ≤130/80 mm Hg and no antihypertensive medications. Improvement in hypertension: BP >130/80 mm Hg and decreased number or dose of medications, or blood pressure ≤130/80 with continued use of medications at constant dose.

RESULTS

At postoperative discharge, 17 (23%, P < .001), 51 (68%, P < .001) and 7 (9%) patients had remission, improvement in hypertension or no change. Twenty-nine had no follow-up. Others achieved remission at 3 (n = 5), 6 (n = 6), or 12-months (n = 5). At the last evaluation, 33/75 (44%) had remission, 36/75 (48%) had improved hypertension and 6 were unchanged. Patients with improvement discontinued a median of one medication (P < .001). At 12-months, 27/42 (64%) patients had normal BP (P < .002). Longer estimated duration of CS (P = .0106), younger age (P = .0022), and lower baseline body mass index (P = .0413) predicted hypertension remission.

CONCLUSIONS

About 80% of CS patients experienced BP normalization or improvement within 10 days of cure, but about half failed to normalize BP by one year. BP should be monitored after cure, and antihypertensive medications adjusted to avoid unwanted cardiovascular effects.

Hypertension and Cardiovascular Mortality in Patients with Cushing Syndrome

Patients with Cushing syndrome have an increased mortality rate, primarily due to increased cardiovascular death, which is driven by hypertension, diabetes, obesity, and dyslipidemia. These should be evaluated before and after active hypercortisolism, and each should be treated specifically. Antihypertensives may be chosen based on probable pathophysiology. Thus, inhibitors of the renin-angiotensinogen system are recommended. Mineralocorticoid antagonists are helpful in hypokalemic patients. Other agents are often needed to normalize blood pressure. If medical treatment of Cushing syndrome is chosen, the goal should be to normalize cortisol (or its clinical action); if this is not achieved, it is more difficult to treat comorbidities.

Steroid withdrawal improves blood pressure control and nocturnal dipping in pediatric renal transplant recipients: analysis of a prospective, randomized, controlled trial

BACKGROUND

Variable effects of steroid minimization strategies on blood pressure in pediatric renal transplant recipients have been reported, but data on the effect of steroid withdrawal on ambulatory blood pressure and circadian blood pressure rhythm have not been published so far.

METHODS

In a prospective, randomized, multicenter study on steroid withdrawal in pediatric renal transplant recipients (n = 42) on cyclosporine, mycophenolate mofetil, and methylprednisolone, we performed a substudy in 28 patients, aged 11.2 ± 3.8 years, for whom ambulatory blood pressure monitoring (ABPM) data were available.

RESULTS

In the steroid-withdrawal group, the percentage of patients with arterial hypertension, defined as systolic and/or diastolic blood pressure values recorded by ABPM > 1.64 SDS and/or antihypertensive medication, at month 15 was significantly lower (35.7%, p = 0.002) than in controls (92.9%). The need of antihypertensive medication dropped significantly by 61.2% (p < 0.000 vs. control), while in controls, it even rose by 69.3%. One year after steroid withdrawal, no patient exhibited hypertensive blood pressure values above the 95th percentile, compared to 35.7% at baseline (p = 0.014) and to 14.3% of control (p = 0.142). The beneficial impact of steroid withdrawal was especially pronounced for nocturnal blood pressure, leading to a recovered circadian rhythm in 71.4% of patients vs. 14.3% at baseline (p = 0.002), while the percentage of controls with an abnormal circadian rhythm (35.7%) did not change.

CONCLUSIONS

Steroid withdrawal in pediatric renal transplant recipients with well-preserved allograft function is associated with less arterial hypertension recorded by ABPM and recovery of circadian blood pressure rhythm by restoration of nocturnal blood pressure dipping.

A Cushing's syndrome patient's severe insomnia and morning blood pressure surge both improved after her left adrenal tumor resection

Underlying mechanisms of the elevated risks of hypertension and cardiovascular disease (CVD) in Cushing's syndrome (CS) are unclear. We treated an adult woman with CS because of a cortisol-secreting adrenal tumor. After tumor resection, the 24-h blood pressure (BP) level improved from 156/91 to 131/84 mmHg; the morning BP surprisingly improved from 174/98 to 127/93 mmHg, although we reduced her antihypertensive medication. Her sleep quality (by the Pittsburgh Sleep Quality Index) improved from 7 to 2 points. Disturbed circadian BP rhythm is often observed in CS, but was reported only as altered nocturnal BP fall. This is the first report showing the disappearance of the morning BP surge evaluated by ambulatory BP monitoring with postsurgery sleep quality improvement. Poor-quality sleep, followed by exaggerated morning BP surge may thus be a cause of CS-related cardiovascular events. Sleep quality and BP circadian rhythm evaluations may clarify hypertension and high CVD risk in CS.

Left ventricular geometry and 24-h blood pressure profile in Cushing's syndrome

Cushing's syndrome (CS) is associated with cardiovascular disease. The impact of the hemodynamic load on left ventricular mass (LVM) in patients with CS is not well known. In fact, the effects of 24-h blood pressure (BP) load and BP circadian rhythm on cardiac structure and function have not been studied. Aim of the present study has thus been to assess the presence of cardiac remodeling in patients with newly diagnosed CS, combining evaluation of cardiac remodeling and assessment of BP burden derived by 24-h ambulatory blood pressure monitoring (ABPM). 25 patients (4 M, 21 F) with CS underwent echocardiography in order to assess cardiac morphology and geometry (relative wall thickness-RWT). As controls, 25 subjects similar for demographic characteristics and 24-h BP were used. CS Patients were similar to controls by age, sex, mean 24-h BP, and body mass index. There was a significant increase in left ventricular mass (LVM; 44.4 ± 14.7 vs. 36.9 ± 10 g/m^2.7, p = 0.03) and a significant increase in RWT (0.46 ± 0.07 vs. 0.41 ± 0.08, p = 0.02) in CS patients compared to controls. The prevalence of CS patients with pressure non-dipping profile was greater than that of controls (56 vs. 16 %, p < 0.05), with no significant association with LVM or geometry. 24-h urinary cortisol was not associated with LVM (r = 0.1, p = 0.5) or RWT (r = 0.02, p = 0.89) in the CS group. In conclusion, LVM and the concentric pattern of the left ventricle are relatively independent from 24-h BP load and profile (dipping/non-dipping) in CS patients.

The hypertension of Cushing's syndrome: controversies in the pathophysiology and focus on cardiovascular complications

Cushing's syndrome is associated with increased mortality, mainly due to cardiovascular complications, which are sustained by the common development of systemic arterial hypertension and metabolic syndrome, which partially persist after the disease remission. Cardiovascular diseases and hypertension associated with endogenous hypercortisolism reveal underexplored peculiarities. The use of exogenous corticosteroids also impacts on hypertension and cardiovascular system, especially after prolonged treatment. The mechanisms involved in the development of hypertension differ, whether glucocorticoid excess is acute or chronic, and the source endogenous or exogenous, introducing inconsistencies among published studies. The pleiotropic effects of glucocorticoids and the overlap of the several regulatory mechanisms controlling blood pressure suggest that a rigorous comparison of in-vivo and in-vitro studies is necessary to draw reliable conclusions. This review, developed during the first ‘Altogether to Beat Cushing's syndrome’ workshop held in Capri in 2012, evaluates the most important peculiarities of hypertension associated with CS, with a particular focus on its pathophysiology. A critical appraisal of most significant animal and human studies is compared with a systematic review of the few available clinical trials. A special attention is dedicated to the description of the clinical features and cardiovascular damage secondary to glucocorticoid excess. On the basis of the consensus reached during the workshop, a pathophysiology-oriented therapeutic algorithm has been developed and it could serve as a first attempt to rationalize the treatment of hypertension in Cushing's syndrome.

cAMP signaling in cortisol-producing adrenal adenoma

The cAMP signaling pathway is one of the major players in the regulation of growth and hormonal secretion in adrenocortical cells. Although its role in the pathogenesis of adrenocortical hyperplasia associated with Cushing's syndrome has been clarified, a clear involvement of the cAMP signaling pathway and of one of its major downstream effectors, the protein kinase A (PKA), in sporadic adrenocortical adenomas remained elusive until recently. During the last year, a report by our group and three additional independent groups showed that somatic mutations of PRKACA, the gene coding for the catalytic subunit α of PKA, are a common genetic alteration in patients with Cushing's syndrome due to adrenal adenomas, occurring in 35-65% of the patients. In vitro studies revealed that those mutations are able to disrupt the association between catalytic and regulatory subunits of PKA, leading to a cAMP-independent activity of the enzyme. Despite somatic PRKACA mutations being a common finding in patients with clinically manifest Cushing's syndrome, the pathogenesis of adrenocortical adenomas associated with subclinical hypercortisolism seems to rely on a different molecular background. In this review, the role of cAMP/PKA signaling in the regulation of adrenocortical cell function and its alterations in cortisol-producing adrenocortical adenomas will be summarized, with particular focus on recent developments.

Alterations in diurnal rhythmicity in patients treated for nonfunctioning pituitary macroadenoma: a controlled study and literature review

OBJECTIVE

Patients treated for nonfunctioning pituitary macroadenomas (NFMAs) have fatigue and alterations in sleep characteristics and sleep-wake rhythmicity frequently. As NFMAs often compress the optic chiasm, these complaints might be related to dysfunction of the adjacent suprachiasmatic nucleus (SCN). We aimed to explore whether indirect indices of SCN functioning are altered in the long term after surgery for NFMAs.

METHODS

We studied 17 NFMA patients in long-term remission after transsphenoidal surgery, receiving adequate and stable hormone replacement for hypopituitarism, and 17 control subjects matched for age, gender, and BMI. Indirect indices of SCN function were assessed from 24-h ambulatory recordings of skin and core body temperatures, blood pressure, and salivary melatonin levels. Altered melatonin secretion was defined as an absence of evening rise, considerable irregularity, or daytime values >3 pg/ml. We additionally studied eight patients treated for craniopharyngioma.

RESULTS

Distal-proximal skin temperature gradient did not differ between NFMAs and control subjects, but proximal skin temperature was decreased during daytime (P=0.006). Core body temperature and non-dipping of blood pressure did not differ, whereas melatonin secretion was often altered in NFMAs (OR 5.3, 95% CI 0.9-30.6). One or more abnormal parameters (≥2.0 SDS of control subjects) were observed during nighttime in 12 NFMA patients and during daytime in seven NFMA patients. Similar patterns were observed in craniopharyngioma patients.

CONCLUSION

Heterogeneous patterns of altered diurnal rhythmicity in skin temperature and melatonin secretion parameters were observed in the majority of patients treated for NFMAs. On a group level, both NFMA and craniopharyngioma patients showed a lower daytime proximal skin temperature than control subjects, but other group averages were not significantly different. The observations suggest altered function of central (or peripheral) clock machinery, possibly by disturbed entrainment or damage of the hypothalamic SCN by the suprasellar macroadenoma or its treatment.

Neutrophil to lymphocyte and platelet to lymphocyte ratio in patients with dipper versus non-dipper hypertension

BACKGROUND

Neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) are associated with worse outcome in various diseases. Non-dipping blood pressure pattern is associated with higher cardiovascular mortality. The aim of this study was to explore the association between NLR and PLR in patients with dipper versus non-dipper hypertension.

METHODS

The study included 166 patients with hypertension. Eighty-three patients (40 male, mean age: 49.1 ± 10.5 years) had dipper hypertension, while 83 patients (41 male, mean age: 52.3 ± 12.7 years) had non-dipper hypertension.

RESULTS

Baseline demographic characteristics were similar in both groups. Patients with non-dipper hypertension had significantly higher NLR compared to dipper hypertension (2.3 ± 0.9 versus 1.8 ± 0.5, p < 0.001). Patients with non-dipper hypertension had significantly higher PLR compared to dipper hypertension (117.7 ± 35.2 versus 100.9 ± 30.5, p = 0.001). In univariate analysis, hyperlipidemia, smoking, presence of diabetes, PLR more than 107 and NLR more than 1.89 were among predictors of dipper and non-dipper status. In logistic regression analyses, only hyperlipidemia (odds ratio: 2.96, CI: 1.22-7.13) and PLR more than 107 (odds ratio: 2.62, CI: 1.13-6.06) were independent predictors of dipper and non-dipper status. A PLR of 107 or higher predicted non-dipper status with a sensitivity of 66.3% and specificity of 68.7%.

CONCLUSION

We demonstrated that patients with non-dipper hypertension had significantly higher NLR and PLR compared to dipper hypertension, which has not been reported previously. Moreover PLR more than 107 but not NLR was independent predictor of non-dipper status.

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.

Clinical relevance of cardiac structure and function abnormalities in patients with Cushing's syndrome before and after cure

OBJECTIVES

  Sustained hypercortisolism impacts cardiac function, and, indeed, cardiac disease is one of the major determinants of mortality in patients with Cushing's syndrome. The aim of this study was to assess the clinical relevance of cardiac structure and function alterations by echocardiography in patients with active Cushing's syndrome and after disease remission.

STUDY DESIGN

  Seventy-one patients (61 women, 10 men) with Cushing's syndrome and 70 age-, sex- and blood pressure-matched controls were enrolled. Echocardiography was performed in 49 patients with active disease and at several time points after remission in 44 patients (median follow-up 46.4 months), and prevalence of abnormal left ventricular mass measurements and systolic and diastolic functions indices was compared between patients with active disease, after remission and controls. Twenty-two patients were evaluated both before and after remission.

RESULTS

  Up to 70% of patients with active Cushing's syndrome presented abnormal left ventricular mass parameters; 42% presented concentric hypertrophy and 23% concentric remodelling. Major indices of systolic and diastolic functions, i.e. ejection fraction and E/A ratio, respectively, were normal. Upon remission of hypercortisolism, left ventricular mass parameters ameliorated considerably, although abnormal values were still more frequent than in controls. Both cortisol excess and hypertension contribute to cardiac mass alterations and increase the prevalence of target organ damage.

CONCLUSIONS

  Cushing's syndrome is associated with an increased risk for abnormalities of cardiac mass, which ameliorates, but does not fully disappear after remission. Systolic and diastolic functions are largely within the normal range in these patients.

Knockout of the vascular endothelial glucocorticoid receptor abrogates dexamethasone-induced hypertension

BACKGROUND

Glucocorticoid-mediated hypertension is incompletely understood. Recent studies have suggested the primary mechanism of this form of hypertension may be through the effects of glucocorticoids on vascular tissues and not to excess sodium and water re-absorption as traditionally believed.

OBJECTIVE

The goal of this study was to better understand the role of the vasculature in the generation and maintenance of glucocorticoid-mediated hypertension.

METHODS

We created a mouse model with a tissue-specific knockout of the glucocorticoid receptor in the vascular endothelium.

RESULTS

We show that these mice are relatively resistant to dexamethasone-induced hypertension. After 1 week of dexamethasone treatment, control animals have a mean blood pressure (BP) increase of 13.1 mmHg, whereas knockout animals have only a 2.7 mmHg increase (P < 0.001). Interestingly, the knockout mice have slightly elevated baseline BP compared with the controls (112.2 ± 2.5 vs. 104.6 ± 1.2 mmHg, P = 0.04), a finding which is not entirely explained by our data. Furthermore, we demonstrate that the knockout resistance arterioles have a decreased contractile response to dexamethasone with only 6.6% contraction in knockout vessels compared with 13.4% contraction in control vessels (P = 0.034). Finally, we show that in contrast to control animals, the knockout animals are able to recover a significant portion of their normal circadian BP rhythm, suggesting that the vascular endothelial glucocorticoid receptor may function as a peripheral circadian clock.

CONCLUSION

Our study highlights the importance of the vascular endothelial glucocorticoid receptor in several fundamental physiologic processes, namely BP homeostasis and circadian rhythm.

Cushing's syndrome: all variants, detection, and treatment

Diagnosis of Cushing's syndrome involves a step-wise approach and establishing the cause can be challenging. Several pathogenic mechanisms have been proposed for glucocorticoid-induced hypertension, including a functional mineralocorticoid excess state, upregulation of the renin angiotensin system, and deleterious effects of cortisol on the vasculature. Surgical excision of the cause of excess glucocorticoids remains the optimal treatment. Antiglucocorticoid and antihypertensive agents and steroidogenesis inhibitors can be used as adjunctive treatment modalities in preparation for surgery and in cases where surgery is contraindicated or has not led to cure.

Increased arterial rigidity in children affected by Cushing's syndrome after successful surgical cure

BACKGROUND

Complications, such as secondary hypertension, probably related to the loss of arterial elasticity, frequently arise in Cushing's syndrome, and may persist even beyond cure. This study aimed at demonstrating that arterial compliance, evaluated by automated recording of the QKd interval, was lower in children after a successful surgery for Cushing's syndrome than in a control group of healthy subjects.

METHODS

In all, 23 young girls aged between 11 and 18 years who had undergone a surgical cure for Cushing syndrome - 18 with a pituitary adenoma, three with a primary adrenal disease, and two suffering from ectopic adrenocorticotrope hormone secretion - were enrolled. Arterial stiffness was measured by the standardised non-invasive QKd 100-60 method. A 24-hour ambulatory blood pressure monitoring and a transthoracic echocardiography were also performed.

RESULTS

The children operated for Cushing's syndrome showed disadvantageous differences in 24-hour ambulatory blood pressure monitoring and in QKD 100-60 value, with p less than 0.01, compared with the control group.

CONCLUSIONS

In spite of its successful surgical cure, Cushing's syndrome results in a significantly decreased arterial distensibility when compared with the control group, which might explain these differences in blood pressure levels. It underlines a significantly higher cardiovascular risk, notwithstanding both the normalisation of cortisol secretion and the very early age of the patients.

Causes and mechanisms of nondipping hypertension

Growing evidence indicates that nondippers have worsened cardiovascular outcomes than dippers. Ambulatory blood pressure monitoring with a lack of nocturnal BP fall (nondipping) have also been shown to be more closely associated with target organ damage and worsened cardiovascular outcome than in patients with essential hypertension with dipping pattern. The underlying pathogenetic mechanisms potentially linking nondipping with cardiovascular disease are not fully understood. There are multiple possible underlying pathophysiologic mechanisms in the impaired BP decline during the night. Extrinsic and intrinsic factors including abnormal neurohormonal regulation, lack of physical activity, nutritional factors such as increased dietary sodium intake, and smoking of tobacco have been implicated for blunted circadian rhythm of BP. Certain diseases such as diabetes and chronic renal diseases also affect the circadian BP rhythm. Currently, the clinical importance of nondipping is known well; however, the relationship between certain disease states and nondipping has not been fully explained yet. This paper will attempt to address to clarify the underlying basis for nondipping and the specific associations with various disease states.

A critical role for vascular smooth muscle in acute glucocorticoid-induced hypertension

Although glucocorticoid (GC)-induced hypertension has commonly been attributed to promiscuous activation of the mineralocorticoid receptor by cortisol, thereby promoting excess reabsorption of sodium and water, numerous lines of evidence indicate that this is not the only or perhaps even the primary mechanism. GC induce a number of effects on vascular smooth muscle (VSM) in vitro that may be pertinent to hypertension, but their contribution in vivo is unknown. To address this question, a mouse model with a tissue-specific knockout (KO) of the GC receptor in the VSM was created and characterized. Similar to control mice, KO mice exhibited normal baseline BP and, interestingly, showed normal circadian variation in BP. When dexamethasone was administered, however, the acute hypertensive response was markedly attenuated in KO mice, and there was a trend toward a decreased chronic hypertensive response. These data suggest that the GC receptor in VSM plays a critical role in the acute hypertensive response to GC in vivo.