Prevalence, diagnosis and outcomes of treatment for primary aldosteronism

Metabolic phenotypes and fatty acid profiles associated with histopathology of primary aldosteronism

Primary aldosteronism (PA) caused by aldosterone hypersecretion is treated by adrenalectomy or medications. Histopathologic examination of resected adrenals reveals diverse histopathologic features. This study aimed to investigate the potential association of peripheral and adrenal tissue metabolic profiles with the histopathologic features of PA. The retrospective study included 105 surgically treated and 43 medically treated patients with PA. Adrenal specimens were categorized according to the HISTALDO (HISTopathology of primary ALDOsteronism) consensus. Peripheral and adrenal tissue metabolic profiles were assessed, including adiposity, adipokines and fatty acid abundances. The distinct fatty acid, arachidonic acid, was further functionally characterized. Surgically treated patients with classical histopathologic findings (n = 71) displayed lower body mass indexes, a lower prevalence of obesity, smaller waist circumference and visceral adipose tissue areas, and lower leptin concentrations compared with operated patients with the nonclassical histopathology (n = 34). No such differences were identified between the nonclassical histopathology group and medically treated group. Distinct concentrations of 18 out of 35 peripheral venous fatty acids, including arachidonic acid, were identified among the 3 groups. Further, accumulation of arachidonic acid was demonstrated in 4 aldosterone-producing adenomas compared with paired adjacent cortex possibly linked with suppressed peroxisomal beta-oxidation. Stimulation of human adrenocortical cells with arachidonic acid or peroxisomal beta-oxidation inhibitor caused 3.8-fold (P = 0.0050) and 1.7-fold (P = 0.0328) amplification of CYP11B2 expression, respectively, which were ablated by BAPTA-AM or KN93, and induced oxidative stress and apoptosis. Our findings show metabolic heterogeneity related to histopathology and support a role for arachidonic acid in PA pathophysiology.

A New Disease Severity Score for Measuring Treatment Response to Adrenalectomy in Patients With Primary Aldosteronism

OBJECTIVE

Cure after adrenalectomy for primary aldosteronism has been reported in only 15% to 40% of patients, with no disease severity score available to measure response objectively. Furthermore, the criteria used to define cure are outdated. This study aims to determine the rate of cure based on the current definition of normal blood pressure and develop a disease severity score to measure clinical improvement after adrenalectomy for primary aldosteronism.

METHODS

This was a retrospective single-center study that included patients who underwent adrenalectomy for primary aldosteronism between 2000 and 2023. Blood pressure, a defined daily dose of antihypertensives, and potassium supplementation were incorporated into a new Primary Aldosteronism Disease Severity Score (PADSS), which was calculated with preoperative and 6-month postoperative parameters.

RESULTS

The study included 201 patients. Adrenalectomy was guided by adrenal venous sampling in 86.1% of patients. The cure rate per the new definition of normal blood pressure was 7.5% (n = 15). The median PADSS was 16.3 (13.6-19.9) preoperatively and decreased to 10 (4.5-13.3) postoperatively. An improvement of the PADSS was observed in 90% (n = 180) of patients at 6 months of adrenalectomy. The median rate of improvement in PADSS was 33.3% (13.8% to 56.6%).

CONCLUSIONS

Although complete cure rates are low after adrenalectomy in primary aldosteronism, especially based on the new definition of normal blood pressure, a clinical improvement is seen in the vast majority of patients postoperatively. The newly introduced PADSS can be used to assess the clinical benefit achieved with adrenalectomy.

NT-proBNP levels in patients with primary hyperaldosteronism and autonomous cortisol cosecretion

CONTEXT

Patients with primary aldosteronism (PA) have higher cardiac comorbidities including more pronounced left ventricular hypertrophy than patients with essential hypertension.

OBJECTIVE

Autonomous cortisol cosecretion (ACS) is a common subtype in PA associated with a worse metabolic profile.

HYPOTHESIS

Autonomous cortisol cosecretion may affect myocardial parameters and result in a worse cardiac outcome compared to patients with PA and without ACS.

METHODS

Three hundred and sixty-seven patients with PA undergoing 1 mg dexamethasone suppression test (DST) and echocardiography at baseline from 2 centers of the German Conn's Registry were included. Follow-up for up to 3.8 years was available in 192 patients.

RESULTS

Patients with PA and ACS had higher NT-proBNP levels at baseline compared to patients with PA without ACS (114 vs 75.6 pg/mL, P = .02), but showed no difference in echocardiography values. NT-proBNP levels showed a significant positive correlation (r = 0.141, P = .011) with cortisol levels after DST at baseline. In response to therapy of PA, NT-proBNP levels decreased, but remained significantly higher in patients with ACS compared to patients without ACS. At follow-up, left ventricle end-diastolic dimension (LVEDD) decreased significantly only in patients without ACS. Left atrial diameter (LAD) decreased significantly in patients without ACS and in female patients with ACS but not in male patients. Left ventricular mass index (LVMI) significantly improved in female patients without ACS but remained unchanged in female patients with ACS as well as in male patients at follow-up.

CONCLUSIONS

In patients with PA, concomitant ACS is associated with a worse cardiac profile and only partial recovery even years after initiation of targeted PA therapy.

Screening parameters for diagnosing primary aldosteronism in patients with moderate to severe obstructive sleep apnea hypopnea syndrome and resistant hypertension

Background

Patients with obstructive sleep apnea hypopnea syndrome (OSAHS) combined with resistant hypertension (RH) have a high risk of developing primary aldosteronism (PA). This study investigated the aldosterone-renin ratio (ARR), plasma aldosterone concentration (PAC), and plasma renin activity (PRA) to determine the optimal cutoff values for PA diagnosis in patients with OSAHS combined with RH.

Methods

Patients diagnosed with moderate and severe OSAHS combined with RH were recruited from the inpatient clinic of the Department of Endocrinology at Ji'an Central Hospital between October 2020 and April 2023. The included patients were divided into PA and no-PA groups. Diagnostic accuracy measures were calculated for each group, and receiver operating characteristic (ROC) curves were generated.

Results

A total of 241 patients were included, of which 103 had positive ARR screening results in the diagnostic accuracy analysis and 66 were diagnosed with PA. PAC and ARR showed moderate predictive capacity for PA, with area under the curve (AUC) values of 0.66 [95% confidence interval (CI): 0.55-0.77] and 0.72 (95% CI: 0.63-0.82), respectively, while PRA exhibited a limited predictive capacity (AUC = 0.51, 95% CI: 0.40-0.63). Using 45 as the optimal cutoff value for ARR, the sensitivity was 86% and the specificity was 52%. The optimal cutoff value for PAC was 17, with a sensitivity of 78% and a specificity of 55%. Notably, in patients with severe OSAHS, ARR at screening demonstrated significant predictive value for PA, with an AUC of 0.84 (95% CI: 0.72-0.96), a sensitivity of 85%, and a specificity of 76%. Conversely, in patients with moderate OSAHS, only ARR demonstrated significant predictive value for PA diagnosis, while PAC did not demonstrate notable diagnostic value.

Conclusion

ARR and PAC are initial screening tools for PA, facilitating early detection, particularly in low-resource settings. In patients with OSAHS and RH, the ARR and PAC thresholds for PA diagnosis may require more stringent adjustment.

A novel clinical-imaging nomogram for predicting primary aldosteronism in patients with hypertension

This study aimed to develop and validate the accuracy of a clinical-imaging index nomogram in predicting primary aldosteronism (PA) in patients with hypertension. This case-control study enrolled 404 hypertension patients in the First Affiliated Hospital of Nanjing Medical University, China, from April 2017 to September 2021. The patients were randomly divided into the training set (n = 283, 70%) and the validation set (n = 121, 30%). Univariate and multivariate logistic regression analyses were performed to identify independent predictors of PA, which were then used construct a nomogram. The receiver operating characteristic (ROC) curve and calibration plot were drawn to assess the predictive value. The accuracies of our nomogram and other known prediction models were compared using decision curve analyses (DCA). Four significant variables (history of hypokalemia [OR = 2.684, 95% CI: 1.281-5.623, P < 0.001], typical imaging feature [OR = 2.316, 95% CI: 1.166-4.601, P = 0.003], 24 h urine potassium [OR = 0.956, 95% CI: 0.932-0.980, P < 0.001], plasma renin activity [PRA] [OR = 1.423, 95% CI: 1.161-1.744, P < 0.001]) in the multivariate logistic regression analysis were sifted out, and used to build the nomogram. The predictive nomogram yielded an AUC of 0.890 (95% CI, 0.853-0.927) in the training set and 0.860 (95% CI, 0.793-0.927) in the validation set. Predicted and actual probability of PA matched well in the nomogram. Moreover, the DCA showed that the nomogram gained a net benefit in clinical practice in predicting PA when the threshold value was set between 0.1 and 1.0. Our four-variable nomogram was accurate in predicting PA patients and might be introduced into clinical management.

Laparoscopic sleeve gastrectomy followed by laparoscopic adrenalectomy for patients with obesity and primary aldosteronism: Report of two patients

INTRODUCTION AND IMPORTANCE

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. Surgical treatment of unilateral PA usually resolves excessive aldosterone secretion. Obesity is an independent factor for postoperative persistent hypertension for patients with unilateral PA. Laparoscopic sleeve gastrectomy has become popular due to its efficacy in resolving obesity. A specific strategy might to be needed for patients with unilateral PA and obesity.

CASE PRESENTATION

Two males with PA and obesity (Body Mass Index: BMIs of 35.9 and 39.0, respectively) were referred for evaluation. Both patients had hypertension caused by PA and obesity. We performed laparoscopic sleeve gastrectomy (LSG) prior to adrenalectomy to avoid persistent postoperative hypertension and perioperative obesity related comorbidities. LSG could lead to decreasing of BMIs to 27.7 and 32.1. Comorbidities associated with obesity were also resolved in both patients. Laparoscopic adrenalectomy was then safely performed in these two patients with PA.

CLINICAL DISCUSSIONS

Patients with PA developing resistant hypertension were estimated to be 20 % of those who underwent adrenalectomy. Decreased BMI can be an independent preoperative determinant for successful outcome after adrenalectomy regarding hypertension. We need to review with special care the preoperative BMI and the nature of hypertension before performing surgery on patients with unilateral PA.

CONCLUSIONS

A successful strategy was used to treat two obese patients with unilateral PA who underwent laparoscopic adrenalectomy after LSG to minimize complications associated with obesity-related comorbidities.

Can expiratory or inspiratory contrast-enhanced computed tomography be more efficient for fast-track cannulation of the right adrenal vein in adrenal venous sampling?

PURPOSE

This study compares the usefulness of expiratory arterial phase (EAP)-contrast-enhanced computed tomography (CT) (CECT) with that of inspiratory arterial phase (IAP)-CECT in adrenal venous sampling (AVS).

METHODS

Sixty-four patients who underwent AVS and CECT at the authors' hospital between April 2013 and June 2019 were included in this study. The patients were classified into the following two groups: EAP (32 patients) and IAP (32 patients) groups. The single arterial phase images were obtained at 40 seconds in the IAP group. The double arterial phase images were obtained at 40 seconds in the early arterial phase and 55 seconds in the late arterial phase in the EAP group. The authors then compared the right adrenal vein (RAV) visualization rate on the CECT, the difference between the CECT images and adrenal venograms in the localization of the RAV orifice, the cannulation time to the RAV, and the volume of contrast agent administered intraoperatively between the two groups.

RESULTS

The rates of the RAV visualization in the EAP group were 84.4% in the early arterial phase, 93.8% in the late arterial phase, and 100% in the combined early and late arterial phases. The rate of the RAV visualization in the IAP group was 96.9%. There was no significant difference between the two groups in terms of the rate of the RAV visualization. However, there was a small difference in the location of the RAV orifice between the CECT images and adrenal venograms in the EAP group as compared with the IAP group (P < 0.001). The median time to the RAV catheterization was significantly shorter in the EAP group (27.5 minutes) than in the IAP group (35.5 minutes; P = 0.035). The rates of the RAV visualization in the EAP group were not significant between the early arterial phase, late arterial phase, and combined early and late arterial phases (P = 0.066). However, the mean volume CT dose index in the combined early and late arterial phases was significantly higher than in the early and late arterial phases (P < 0.001).

CONCLUSION

The EAP-CECT is more useful for increasing the speed of the RAV cannulation due to the small difference in the localization of the RAV orifice compared to IAP-CECT. However, since EAP-CECT has double contrast arterial phases and increased radiation exposure compared to IAP-CECT, only the late arterial phase may be acceptable to reduce radiation exposure.

Prevalence of High Aldosterone-Renin Ratio in Patients With Hypertension in Basrah

BACKGROUND AND AIM

Aldosterone-renin ratio (ARR) is an important screening tool for the assessment of primary aldosteronism as a cause of secondary hypertension. This study aimed to measure the prevalence of patients with elevated ARR among samples of Iraqi patients with hypertension.

METHODS

A retrospective study was conducted at Faiha Specialized Diabetes, Endocrine and Metabolism Center (FDEMC) in Basrah during the period of February 2020 to November 2021. We evaluated the records of patients with hypertension whom were screened for endocrine cause, and an ARR cut-off equal or more than 5.7 was considered elevated.

RESULTS

Of the total 150 patients enrolled, 39 (26%) of them had an elevated ARR. No statistically significant association for the elevated ARR with age, gender, BMI, duration of hypertension, systolic and diastolic blood pressure, pulse rate, and presence or absence of diabetes mellitus or lipid profile.

CONCLUSION

High frequency of elevated ARR was seen in 26% of patients with hypertension. More studies need to be conducted in the future taking larger samples.

Anatomical and functional remodeling of left ventricle in patients with primary aldosteronism and concomitant albuminuria

Background

Primary aldosteronism (PA) is the leading cause of secondary hypertension globally and is associated with adverse cardiovascular outcomes. However, the cardiac impact of concomitant albuminuria remains unknown.

Objective

To compare anatomical and functional remodeling of left ventricle (LV) in PA patients with or without albuminuria.

Design

Prospective cohort study.

Methods

The cohort was separated into two arms according to the presence or absence of albuminuria (>30 mg/g of morning spot urine). Propensity score matching with age, sex, systolic blood pressure, and diabetes mellitus was performed. Multivariate analysis was conducted with adjustments for age, sex, body mass index, systolic blood pressure, duration of hypertension, smoking, diabetes mellitus, number of antihypertensive agents, and aldosterone level. A local-linear model with bandwidth of 2.07 was used to study correlations.

Results

A total of 519 individuals with PA were enrolled in the study, of whom 152 had albuminuria. After matching, the albuminuria group had a higher creatinine level, at baseline. With regard to LV remodeling, albuminuria was independently associated with a significantly higher interventricular septum (1.22 > 1.17 cm, p = 0.030), LV posterior wall thickness (1.16 > 1.10 cm, p = 0.011), LV mass index (125 > 116 g/m², p = 0.023), and medial E/e' ratio (13.61 > 12.30, p = 0.032), and a lower medial early diastolic peak velocity (5.70 < 6.36 cm/s, p = 0.016). Multivariate analysis further revealed that albuminuria was an independent risk factor for elevated LV mass index (p < 0.001) and medial E/e' ratio (p = 0.010). Non-parametric kernel regression also demonstrated that the level of albuminuria was positively correlated with LV mass index. The remodeling of LV mass and diastolic function under the presence of albuminuria distinctly improved after PA treatment.

Conclusion

The presence of concomitant albuminuria in patients with PA was associated with pronounced LV hypertrophy and compromised LV diastolic function. These alterations were reversible after treatment for PA.

Plain language summary

Cardiac Impact of Primary Aldosteronism and Albuminuria Primary aldosteronism and albuminuria has been, respectively, demonstrated to bring about left ventricular remodeling, but the aggregative effect was unknown. We constructed a prospective single-center cohort study in Taiwan. We proposed the presence of concomitant albuminuria was associated with left ventricular hypertrophy and compromised diastolic function. Intriguingly, management of primary aldosteronism was able to restore these alterations. Our study delineated the cardiorenal crosstalk in the setting of secondary hypertension and the role of albuminuria for left ventricular remodeling. Future interrogations toward the underlying pathophysiology as well as therapeutics will facilitate the improvement of holistic care for such population.

CT-based radiomics nomogram for differentiation of adrenal hyperplasia from lipid-poor adenoma: an exploratory study

BACKGROUND

To establish and verify a radiomics nomogram for differentiating isolated micronodular adrenal hyperplasia (iMAD) from lipid-poor adenoma (LPA) based on computed tomography (CT)-extracted radiomic features.

METHODS

A total of 148 patients with iMAD or LPA were divided into three cohorts: a training cohort (n = 72; 37 iMAD and 35 LPA), a validation cohort (n = 36; 22 iMAD and 14 LPA), and an external validation cohort (n = 40; 20 iMAD and 20 LPA). Radiomics features were extracted from contrast-enhanced and non-contrast CT images. The least absolute shrinkage and selection operator (LASSO) method was applied to develop a triphasic radiomics model and unenhanced radiomics model using reproducible radiomics features. A clinical model was constructed using certain laboratory variables and CT findings. Radiomics nomogram was established by selected radiomics signature and clinical factors. Nomogram performance was assessed by calibration curve, the areas under receiver operating characteristic curves (AUC), and decision curve analysis (DCA).

RESULTS

Eleven and eight extracted features were finally selected to construct an unenhanced radiomics model and a triphasic radiomics model, respectively. There was no significant difference in AUC between the two models in the external validation cohort (0.838 vs. 0.843, p = 0.949). The radiomics nomogram inclusive of the unenhanced model, maximum diameter, and aldosterone showed the AUC of 0.951, 0.938, and 0.893 for the training, validation, and external validation cohorts, respectively. The nomogram showed good calibration, and the DCA demonstrated the superiority of the nomogram compared with the clinical factors model alone in terms of clinical usefulness.

CONCLUSIONS

A radiomics nomogram based on unenhanced CT images and clinical variables showed favorable performance for distinguishing iMAD from LPA. In addition, an efficient unenhanced model can help avoid extra contrast-enhanced scanning and radiation risk.

Cardiovascular and metabolic characters of KCNJ5 somatic mutations in primary aldosteronism

BACKGROUND

Primary aldosteronism (PA) is the leading cause of curable endocrine hypertension, which is associated with a higher risk of cardiovascular and metabolic insults compared to essential hypertension. Aldosterone-producing adenoma (APA) is a major cause of PA, which can be treated with adrenalectomy. Somatic mutations are the main pathogenesis of aldosterone overproduction in APA, of which KCNJ5 somatic mutations are most common, especially in Asian countries. This article aimed to review the literature on the impacts of KCNJ5 somatic mutations on systemic organ damage.

EVIDENCE ACQUISITION

PubMed literature research using keywords combination, including "aldosterone-producing adenoma," "somatic mutations," "KCNJ5," "organ damage," "cardiovascular," "diastolic function," "metabolic syndrome," "autonomous cortisol secretion," etc.

RESULTS

APA patients with KCNJ5 somatic mutations are generally younger, female, have higher aldosterone levels, lower potassium levels, larger tumor size, and higher hypertension cure rate after adrenalectomy. This review focuses on the cardiovascular and metabolic aspects of KCNJ5 somatic mutations in APA patients, including left ventricular remodeling and diastolic function, abdominal aortic thickness and calcification, arterial stiffness, metabolic syndrome, abdominal adipose tissue, and correlation with autonomous cortisol secretion. Furthermore, we discuss modalities to differentiate the types of mutations before surgery.

CONCLUSION

KCNJ5 somatic mutations in patients with APA had higher left ventricular mass (LVM), more impaired diastolic function, thicker aortic wall, lower incidence of metabolic syndrome, and possibly a lower incidence of concurrent autonomous cortisol secretion, but better improvement in LVM, diastolic function, arterial stiffness, and aortic wall thickness after adrenalectomy compared to patients without KCNJ5 mutations.

Meta-analysis of blood parameters related to lipid and glucose metabolism between two subtypes of primary aldosteronism

It remains unclear whether metabolic profiles differ within the subtypes of primary aldosteronism (PA). This meta-analysis aimed to compare the blood parameters related to lipid and glucose metabolism at baseline between unilateral PA and bilateral PA. A search was performed using PubMed, Web of Science, and Sciencedirect databases, supplemented by hand-searching of related references. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated for each parameter. Twenty-one studies involving 4197 patients with PA were included. Compared with bilateral PA groups, unilateral PA groups demonstrated significantly lower low-density lipoprotein cholesterol (LDL-C, SMD: -.14 mmol/L, 95% CI: -.20, -.07), total cholesterol (TC, SMD: -.16 mmol/L, 95% CI: -.23, -.09), triglyceride (TG, SMD: -.22 mmol/L, 95% CI: -.29, -.16), fasting blood glucose (FBG, SMD: -.11 mmol/L, 95% CI: -.18, -.04), hemoglobin A1c (HbA1c, SMD: -.21%, 95% CI: -.30, -.13), and homeostasis model assessment-insulin resistance (HOMA-IR, SMD: -.40, 95% CI: -.58, -.23). No significant difference was found in high-density lipoprotein cholesterol (HDL-C) level between the two groups (SMD: .40 mmol/L, 95% CI: -.02, .11). To sum up, comparison of several blood metabolic parameters between the two subtypes suggested that the bilateral PA may associate with a higher prevalence of impaired glucose and lipid metabolism than unilateral PA; however, results should be treated with caution. Additional well-designed studies are needed to prove the present results and better elucidate the link between metabolic abnormalities and etiologies of each PA subtype.

Comparison of Echocardiographic Changes Between Surgery and Medication Treatment in Patients With Primary Aldosteronism

Background

Primary aldosteronism can cause cardiac dysfunction, including left ventricular hypertrophy, left ventricular diastolic dysfunction, and left atrial enlargement. A few studies have compared the cardioprotective effects between surgery and medication for primary aldosteronism, although most have not adjusted for baseline disease status. In this study, we investigated the difference in cardiovascular outcomes between surgery and medication treatment for primary aldosteronism after adjusting for baseline clinical characteristics, including aldosterone level and pretreatment echocardiographic information.

Methods and Results

We retrospectively analyzed 220 patients diagnosed with primary aldosteronism who underwent adrenalectomy (n=144) or medication treatment (n=76) between 2009 and 2019. Echocardiographic changes were evaluated pretreatment and 1 year posttreatment. The surgery group had lower potassium, lower plasma renin activity, and higher plasma aldosterone concentration than the medication group, indicating a severe primary aldosteronism phenotype in the former. The decrease in left ventricular mass index after treatment was significantly greater in the surgery group than in the medication group (P=0.047). However, this relationship was not noted after multivariable regression analysis (standard β=−0.08, P=0.17). Additionally, decreased parameter values related to left ventricular diastolic dysfunction and left atrial enlargement were not different between the groups. Pretreatment echocardiographic values were most associated with changes in all echocardiographic parameters. The findings were consistent in the propensity score‐matched analysis.

Conclusions

This study's findings suggest that there is no difference in cardioprotective efficacy between surgical and medication treatment under similar disease severity; however, it should be considered that several study participants with severe hyperaldosteronism were managed surgically.

Differences in Glycemic Abnormalities Between Primary Aldosteronism and Essential Hypertension: A Systematic Review and Meta-Analysis

Background

The relationship of glycemic abnormalities between primary aldosteronism (PA) patients and essential hypertension (EH) patients is still debatable. This meta-analysis aimed to explore differences in the prevalence of glycemic abnormalities and levels of abnormal glucose metabolism in PA and EH patients.

Methods

A search was performed using PubMed, Scopus, Cochrane and Web of Science databases from their inception through January 2022. Inclusion criteria for this study were 1) observational studies which contained specific data of interest, 2) studies including data which compared adult PA and EH patients and 3) studies which used appropriate methods to diagnose PA. Risk ratio (RR) or standardized mean difference (SMD) with a 95% confidence interval (95% CI) was calculated.

Results

Twenty-six studies involving 53,186 patients were included in the meta-analysis. Patients with PA demonstrated significantly higher overall incidence of glycemic abnormalities than patients with EH [RR 1.54; 95% CI (1.20,1.98)]. Risk of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in PA patients were higher than in EH patients [RR 1.27; 95%CI (1.08, 1.49) and RR 2.99; 95%CI (1.74, 5.16), respectively]. There was no statistically significant difference of risk between these groups for impaired fasting glucose (IFG) [RR 1.70; 95%CI (0.55, 5.26)]. Moderate heterogeneity was observed in overall glycemic abnormalities outcomes. A high level of heterogeneity was observed for IFG, while the level was low for DM and IGT.

Conclusions

PA patients have a higher risk of glycemic abnormalities than in EH patients. Further study should be conducted to investigate underlying mechanisms of glycemic abnormalities in PA.

Systematic Review Registration

www.inplasy.com, INPLASY, identifier 202220004.

High Prevalence of Autonomous Aldosterone Production in Hypertension: How to Identify and Treat It

PURPOSE OF REVIEW

Primary aldosteronism (PA) affects millions of individuals worldwide. When unrecognized, PA leads to cardiovascular and renal complications via mechanisms independent from those mediated by hypertension. In this review, we emphasize the importance of PA screening in at-risk populations, and we provide options for customized PA therapy, with consideration for a variety of clinical care settings.

RECENT FINDINGS

Compelling evidence puts PA at the forefront of secondary hypertension etiologies. Cardiovascular and renal damage likely begins in early stages of renin-independent aldosterone excess. PA must be considered not only in patients with resistant hypertension or hypokalemia, but also when hypertension is associated with obstructive sleep apnea or atrial fibrillation, or in those with early-onset hypertension. Screening with plasma aldosterone and renin is widely accessible, and targeted PA therapy can successfully circumvent the excess cardiorenal risk relative to equivalent primary hypertension. Identifying and treating PA in early stages provide opportunities for personalized hypertension therapy in a large number of patients. Additionally, early targeted therapy of PA is essential for pivoting the care of such patients from reactive to preventive of cardiovascular and renal morbidity and mortality.

[Diagnosis and therapy of primary aldosteronism: new aspects]

Primary aldosteronism represents the most frequent cause of endocrine hypertension. It is associated with a higher morbidity and mortality compared to essential hypertension. Early identification of the affected patients is crucial, as the adequate therapy leads to an excellent long-term prognosis, especially after unilateral adrenalectomy. Diagnosis consists of three steps: diagnosis, confirmation test and subtype differentiation. The 2 most frequent causes of primary aldosteronism are aldosterone producing adenoma, which can be cured by surgery, and idiopathic bilateral adrenal hyperplasia, which is treated with mineralocorticoid receptor antagonists.Screening by aldosterone-to-renin ratio is recommended in designed risk populations. As the aldosterone-to-renin ratio displays a limited sensitivity and specificity, confirmatory testing is recommended in most patients with positive screening test. Prediction scores allow to skip confirmatory testing under certain circumstances. Adrenal vein sampling still represents the gold standard in subtype differentiation of primary aldosteronism. Steroid profiling could possibly make dispensable adrenal vein sampling in patients with bilateral hyperplasia. Different studies investigate the potential of functional imaging for differential diagnosis of primary aldosteronism.

Novel chemiluminescent immunoassay to measure plasma aldosterone and plasma active renin concentrations for the diagnosis of primary aldosteronism

Determination of plasma aldosterone concentrations (PAC) and plasma active renin concentrations (ARC) is essential for the diagnosis of primary aldosteronism (PA). In Japan, although PAC and ARC are measured by radioimmunoassay and immunoradiometric assay, respectively, non-radioisotopic methods with better detection sensitivity, measurement accuracy, and technical simplicity are needed. We developed two-site sandwich chemiluminescent enzyme immunoassays (CLEIAs) to measure both PAC and ARC using monoclonal antibodies immobilized onto ferrite particles. The results of both assays are obtained simultaneously from a single plasma sample within 30 min using a fully automated system. The novel CLEIAs were validated using plasma samples from patients with PA (n = 52) and essential hypertension (n = 23). The PAC determined by the CLEIA was significantly correlated with that measured by liquid chromatography/mass spectrometry or conventional radioimmunoassay. The ARC determined by the CLEIA was significantly correlated with that measured by immunoradiometric assay. The limits of detection of the CLEIAs for PAC and ARC were 0.1 ng/dl and 0.04 pg/ml, respectively, which were better than those of conventional methods (PAC: 2.5 ng/dl; ARC: 5 pg/ml). The PAC and PAC/ARC ratio (ARR) were significantly higher, and the ARC significantly lower, in patients with PA than in those with essential hypertension. An ARR cut-off of 1.31 ng/dl per pg/ml showed a sensitivity of 96.2% and specificity of 78.3% for PA screening. The newly developed CLEIAs for measuring PAC and ARC could provide a clinically powerful alternative to conventional methods used for hypertension screening in clinical practice.

Diagnostic value of aldosterone to renin ratio calculated by plasma renin activity or plasma renin concentration in primary aldosteronism

Background:

Since the diagnostic value of aldosterone to renin ratio (ARR) calculated by plasma renin concentration (PRC) or plasma renin activity (PRA) is still inconclusive, we conducted a meta-analysis by systematically reviewing relevant literature to explore the difference in the diagnostic efficacy of ARR calculated by PRC or PRA, so as to provide guidance for clinical diagnosis.

Methods:

We searched PubMed, Embase, and Cochrane Library from the establishment of the database to March 2021. We included studies that report the true positive, false positive, true negative, and false negative values for the diagnosis of primary aldosteronism, and we excluded duplicate publications, research without full text, incomplete information, or inability to conduct data extraction, animal experiments, reviews, and systematic reviews. STATA 15.1 was used to analyze the data.

Results:

The pooled results showed that ARR (plasma aldosterone concentration [PAC]/PRC) had a sensitivity of 0.82 (95% confidence interval [CI]: 0.78–0.86), a specificity of 0.94 (95% CI: 0.92–0.95), a positive-likelihood ratio (LR) of 12.77 (95% CI: 7.04–23.73), a negative LR of 0.11 (95% CI: 0.07–0.17), and symmetric area under the curve (SAUC) of 0.982, respectively. Furthermore, the diagnostic odds ratio (DOR) of ARR (PAC/PRC) was 180.21. Additionally, the pooled results showed that ARR (PAC/PRA) had a sensitivity of 0.91 (95% CI: 0.86–0.95), a specificity of 0.91 (95% CI: 0.90–0.93), a positive LR of 7.30 (95% CI: 2.99–17.99), a negative LR of 0.10 (95% CI: 0.04–0.26), and SAUC of 0.976, respectively. The DOR of ARR (PAC/PRA) was 155.52. Additionally, we conducted a subgroup analysis for the different thresholds (<35 or ≥35) of PAC/PRC. The results showed that the DOR of the cut-off ≥35 groups was higher than the cut-off <35 groups (DOR = 340.15, 95% CI: 38.32–3019.66; DOR = 116.40, 95% CI = 23.28–581.92).

Conclusions:

The research results suggest that the determination of ARR (PAC/PRC) and ARR (PAC/PRA) was all effective screening tools for PA. The diagnostic accuracy and diagnostic value of ARR (PAC/PRC) are higher than ARR (PAC/PRA). In addition, within a certain range, the higher the threshold, the better the diagnostic value.

Prevalence of Primary Aldosteronism Across the Stages of Hypertension Based on a New Combined Overnight Test

Primary aldosteronism (PA) is the most common endocrine cause of arterial hypertension. Despite the increasing incidence of hypertension worldwide, the true prevalence of PA in hypertension was only recently recognized. The objective of the work was to estimate the prevalence of PA in patients at different stages of hypertension based on a newly developed screening-diagnostic overnight test. This is a prospective study with hypertensive patients (n=265) at stage I (n=100), II (n=88), and III (n=77) of hypertension. A group of 103 patients with essential hypertension without PA was used as controls. PA diagnosis was based on a combined screening-diagnostic overnight test, the Dexamethasone-Captopril-Valsartan Test (DCVT) that evaluates aldosterone secretion after pharmaceutical blockade of angiotensin-II and adrenocorticotropic hormone. DCVT was performed in all participants independently of the basal aldosterone to renin ratio (ARR). The calculated upper normal limits for post-DCVT aldosterone levels [3 ng/dl (85 pmol/l)] and post-DCVT ARR [0.32 ng/dl/μU/ml (9 pmol/IU)] from controls, were applied together to establish PA diagnosis. Using these criteria PA was confirmed in 80 of 265 (30%) hypertensives. The prevalence of PA was: 21% (21/100) in stage I, 33% (29/88) in stage II, and 39% (30/77) in stage III. Serum K⁺ levels were negatively correlated and urinary K⁺ was positively correlated in PA patients with post-DCVT ARR (r=-0.349, p <0.01, and r=0.27, p <0.05 respectively). In conclusion, DCVT revealed that PA is a highly prevalent cause of hypertension. DCVT could be employed as a diagnostic tool in all subjects with arterial hypertension of unknown cause.

Primary Aldosteronism: a Continuum from Normotension to Hypertension

PURPOSE OF REVIEW

Primary aldosteronism (PA) is the most common cause of secondary hypertension. Emerging evidence suggests that PA is associated with cardiovascular, metabolic, and renal complications, that likely develop insidiously, due to prolonged inappropriate mineralocorticoid receptor activation. In this review, we discuss the expanding clinical and pathological spectrum of PA.

RECENT FINDINGS

Clinical and molecular studies conducted over the recent years reveal that PA traverses a series of contiguous stages. Pre-clinical, but hormonally overt PA has been identified in patients with normal blood pressure, and such patients harbor an increased risk of developing hypertension. Similarly, genetic and histopathological advancements have exposed a spectrum of PA pathology that corresponds to a continuum that spans from pre-clinical stages to florid PA. PA evolves from pre-hypertensive stages to resistant hypertension, along with serious cardiovascular and renal consequences. Early recognition of PA and targeted therapy will be essential for cardiovascular morbidity and mortality prevention in a large number of patients.

DNA Methylation of the Angiotensinogen Gene, AGT, and the Aldosterone Synthase Gene, CYP11B2 in Cardiovascular Diseases

Angiotensinogen (AGT) and aldosterone play key roles in the regulation of blood pressure and are implicated in the pathogenesis of cardiovascular diseases. DNA methylation typically acts to repress gene transcription. The aldosterone synthase gene CYP11B2 is regulated by angiotensin II and potassium. DNA methylation negatively regulates AGT and CYP11B2 expression and dynamically changes in response to continuous promoter stimulation of each gene. High salt intake and excess circulating aldosterone cause DNA demethylation around the CCAAT-enhancer-binding-protein (CEBP) sites of the ATG promoter region, thereby converting the phenotype of AGT expression from an inactive to an active state in visceral adipose tissue and heart. A close association exists between low DNA methylation at CEBP-binding sites and increased AGT expression in salt-sensitive hypertensive rats. Salt-dependent hypertension may be partially affected by increased cardiac AGT expression. CpG dinucleotides in the CYP11B2 promoter are hypomethylated in aldosterone-producing adenomas. Methylation of recognition sequences of transcription factors, including CREB1, NGFIB (NR4A1), and NURR1 (NR4A2) diminish their DNA-binding activity. The methylated CpG-binding protein MECP2 interacts directly with the methylated CYP11B2 promoter. Low salt intake and angiotensin II infusion lead to upregulation of CYP11B2 expression and DNA hypomethylation in the adrenal gland. Treatment with the angiotensin II type 1 receptor antagonist decreases CYP11B2 expression and leads to DNA hypermethylation. A close association between low DNA methylation and increased CYP11B2 expression are seen in the hearts of patients with hypertrophic cardiomyopathy. These results indicate that epigenetic regulation of both AGT and CYP11B2 contribute to the pathogenesis of cardiovascular diseases.

Outcomes of Adrenalectomy and the Aldosteronoma Resolution Score in the Black and Hispanic Population

Background

Outcomes after adrenalectomy in patients with primary aldosteronism (PA) are variable. The aldosteronoma resolution score (ARS) uses preoperative variables to calculate a score that identifies those patients that are more likely to have resolution of hypertension after adrenalectomy. We aim to determine the efficacy of adrenalectomy and whether the ARS accurately predicts clinical success in a Black and Hispanic population.

Methods

We reviewed patients who underwent adrenalectomy for PA from 2004 to 2018 at two academic centers treating primarily Hispanic and Black patients. Postoperative outcomes were evaluated based on the primary aldosteronism surgical outcome consensus criterion. Retrospectively, the accuracy of ARS was determined by a receiver operating characteristic curve and the area under the curve (AUC).

Results

Forty-three Hispanic and 10 Black patients underwent adrenalectomy for PA. Twenty-two patients (41.5%) had complete clinical success. Variables associated with complete clinical success in the univariate analysis were female gender (p = 0.026), younger age (p = 0.001), lower preoperative aldosterone (p = 0.035), lower preoperative systolic blood pressure (p = 0.001), fewer number of preoperative antihypertensive medications (p = 0.007) and a higher ARS (p = 0.003). On multivariate analysis, only fewer number of preoperative antihypertensive medications was independently associated with complete clinical success (p = 0.026). The AUC of the ARS was 0.746.

Conclusion

The rate of clinical success from adrenalectomy is good for Hispanic and Black patients with PA. Our analysis shows that the ARS is an accurate test of clinical success in Hispanic and Black patients. The ARS may be utilized preoperatively to frame expectations after adrenalectomy in these populations.

The Role of Aldosterone in OSA and OSA-Related Hypertension

Obstructive sleep apnea (OSA) is regarded as an independent risk factor for hypertension. The possible mechanism includes oxidative stress, endothelial injury, sympathetic excitement, renin-angiotensin-aldosterone system activation, etc. Clinical studies have found that there is a high coexistence of OSA and primary aldosteronism in patients with hypertension and that elevated aldosterone levels are independently associated with OSA severity in resistant hypertension. The underlying mechanism is that aldosterone excess can exacerbate OSA through increasing overnight fluid shift and affecting the mass and function of upper airway muscles during the sleep period. Thus, a bidirectional influence between OSA and aldosterone exists and contributes to hypertension in OSA patients, especially resistant hypertension.

Functional Characteristic and Significance of Aldosterone-Producing Cell Clusters in Primary Aldosteronism and Age-Related Hypertension

Primary aldosteronism (PA) is one of the most frequent curable forms of secondary hypertension. It can be caused by the overproduction of aldosterone in one or both adrenal glands. The most common subtypes of PA are unilateral aldosterone over-production due to aldosterone-producing adenomas (APA) or bilateral aldosterone over-production due to bilateral hyperaldosteronism (BHA). Utilizing the immunohistochemical (IHC) detection of aldosterone synthase (CYP11B2) has allowed the identification of aldosterone-producing cell clusters (APCCs) with unique focal localization positive for CYP11B2 expression in the subcapsular portion of the human adult adrenal cortex. The presence of CYP11B2 supports that synthesis of aldosterone can occur in these cell clusters and therefore might contribute to hyperaldosteronism. However, the significance of the steroidogenic properties of APCCs especially in regards to PA remains unclear. Herein, we review the available evidence on the presence of APCCs in normal adrenals and adrenal tissues adjacent to APAs, their aldosterone-stimulating somatic gene mutations, and their accumulation during the ageing process; raising the possibility that APCCs may play a role in the development of PA and age-related hypertension.

Prevalence, Subtype Classification, and Outcomes of Treatment of Primary Aldosteronism: A Prospective Study in China

OBJECTIVE

To investigate the prevalence of primary aldosteronism (PA) among participants with hypertension, evaluate the concordance of PA classification between adrenal computed tomography and adrenal venous sampling, and compare the outcomes of surgery and medication for unilateral PA.

METHODS

A prospective study was conducted among all inpatients with hypertension (n = 7594) at the National Center for Cardiovascular Diseases, China, from May 2016 to April 2018.

RESULTS

Of the 7594 participants, 8.12% (n = 617) with plasma aldosterone-renin ratio ≥3.7 were possible PA cases. Three hundred sixty-seven cases with plasma aldosterone-renin ratio ≥3.7 and plasma aldosterone concentration ≥10 ng/dL were confirmed using the recumbent saline infusion test (69.20%, 182 of 263) or the captopril challenge test (66.5%, 69 of 104, P > .05). The prevalence of PA was 3.31% (n = 251). Of the 251 patients with PA, all of them had multiple comorbidities, and 49.40% (n = 124) had spontaneous hypokalemia. The concordance of PA classification between adrenal computed tomography and adrenal venous sampling was only 47.11%. The patients' blood pressure declined to normal ranges in the adrenalectomy (85.71%, 30 of 35) and spironolactone (63.04%; 29 of 46) groups (P < .05). Furthermore, hypokalemia was normalized in the adrenalectomy (100.00%; 26 of 26) and spironolactone (94.74%; 18 of 19) groups.

CONCLUSION

It is necessary to incorporate PA screening into routine practice for those with hypertension in the Chinese population. This will assist in ensuring that the best therapeutic schedule based on PA subtypes is devised. Additionally, as a result, it may contribute to restoring the blood pressure levels and reducing the prevalence of comorbidities in these patients with PA.

Application of adrenal maximum standardized uptake value to 131I-6β-iodomethyl-19-norcholesterol SPECT/CT for characterizing unilateral hyperfunctioning adrenocortical masses

PURPOSE

To evaluate the maximum standardized uptake value (SUVmax) by ¹³¹I-6β-iodomethyl-19-norcholesterol (NP-59) single-photon emission computed tomography (SPECT)/computed tomography (CT) for characterizing unilateral hyperfunctioning adrenocortical masses.

METHODS

Ten patients underwent NP-59 SPECT/CT to evaluate the following unilateral adrenocortical hyperfuncting masses: three with Cushing's syndrome (CS), three with subclinical CS, and four with primary aldosteronism (PA). Visual and quantitative or semiquantitative analyses (noncontrast CT HU [Hounsfield units], lesion SUVmax, contralateral SUVmax, and SUVmax ratio [lesion SUVmax/contralateral adrenal SUVmax]) were performed. The Mann-Whitney U test or Chi-squared test was used appropriately to assess differences between quantitative variables or compare categorical data. Diagnostic performance was evaluated by receiver operating characteristic (ROC) curve analysis.

RESULTS

All adrenal tumors were diagnosed as cortical adenomas. On visual analysis, unilateral uptake was noted in three patients with CS and one patient with subclinical CS, whereas bilateral uptake was noted in four patients with PA and two patients with subclinical CS (p = 0.046). No significant difference was observed in CT HU (p = 0.055). The lesion SUVmax and SUVmax ratio were significantly higher and the contralateral SUVmax was significantly lower in six patients with CS than in four patients with PA (each, p < 0.05). The area under the ROC curve and accuracy for differentiating between CS and PA were, respectively, 0.92 and 90.0 % for the lesion SUVmax, 1.00 and 100 % for the contralateral SUVmax, and 0.92 and 90.0 % for the SUVmax ratio.

CONCLUSIONS

Quantitative or semiquantitative analysis using the adrenal SUVmax in adrenocortical NP-59 SPECT/CT has potential for characterizing unilateral hyperfunctioning adrenocortical masses.

The Potential Role of Aldosterone-Producing Cell Clusters in Adrenal Disease

Primary aldosteronism (PA) is the most common cause of secondary hypertension. The hallmark of PA is adrenal production of aldosterone under suppressed renin conditions. PA subtypes include adrenal unilateral and bilateral hyperaldosteronism. Considerable progress has been made in defining the role for somatic gene mutations in aldosterone-producing adenomas (APA) as the primary cause of unilateral PA. This includes the use of next-generation sequencing (NGS) to define recurrent somatic mutations in APA that disrupt calcium signaling, increase aldosterone synthase (CYP11B2) expression, and aldosterone production. The use of CYP11B2 immunohistochemistry on adrenal glands from normal subjects, patients with unilateral and bilateral PA has allowed the identification of CYP11B2-positive cell foci, termed aldosterone-producing cell clusters (APCC). APCC lie beneath the adrenal capsule and like APA, many APCC harbor somatic gene mutations known to increase aldosterone production. These findings suggest that APCC may play a role in pathologic progression of PA. Herein, we provide an update on recent research directed at characterizing APCC and also discuss the unanswered questions related to the role of APCC in PA.

Progress in Primary Aldosteronism 2019: New Players on the Block?

Primary aldosteronism (PA) is characterized by hypertension caused by inappropriately high adrenal aldosterone secretion, consecutively low plasma renin, and an elevated aldosterone to renin ratio. It is nowadays the universally accepted main cause of endocrine hypertension. According to the most recent epidemiological data, PA is present in 5.8% of unselected hypertensives in primary care, 6-12% of hypertensives treated in hypertension centers, and up to 30% in subjects with resistant hypertension 1. Despite this high prevalence, a recent survey demonstrated that screening for PA is not universally followed. Renin and aldosterone measurements, the basis for PA screening, are currently performed by only 7% of general practitioners in Italy and 8% in Germany 2. Accordingly, the prevalence of PA was low with 1% among hypertensives in Italy and 2% in Germany. In a retrospective cohort study of 4660 patients with resistant hypertension in California the screening rate for PA was 2.1% 3. Based on these data, it is clear that we still miss the majority of PA cases, despite advances in diagnosis and therapy.