Primary aldosteronism: a common cause of resistant hypertension

Commensal microbiota regulate aldosterone

The gut microbiome regulates many important host physiological processes associated with cardiovascular health and disease; however, the impact of the gut microbiome on aldosterone is unclear. Investigating whether gut microbiota regulate aldosterone can offer novel insights into how the microbiome affects blood pressure. In this study, we aimed to determine whether gut microbiota regulate host aldosterone. We used enzyme-linked immunosorbent assays (ELISAs) to assess plasma aldosterone and plasma renin activity (PRA) in female and male mice in which gut microbiota are intact, suppressed, or absent. In addition, we examined urinary aldosterone. Our findings demonstrated that when the gut microbiota is suppressed following antibiotic treatment, there is an increase in plasma and urinary aldosterone in both female and male mice. In contrast, an increase in PRA is seen only in males. We also found that when gut microbiota are absent (germ-free mice), plasma aldosterone is significantly increased compared with conventional animals (in both females and males), but PRA is not. Understanding how gut microbiota influence aldosterone levels could provide valuable insights into the development and treatment of hypertension and/or primary aldosteronism. This knowledge may open new avenues for therapeutic interventions, such as probiotics or dietary modifications to help regulate blood pressure via microbiota-based changes to aldosterone.NEW & NOTEWORTHY We explore the role of the gut microbiome in regulating aldosterone, a hormone closely linked to blood pressure and cardiovascular disease. Despite the recognized importance of the gut microbiome in host physiology, the relationship with circulating aldosterone remains largely unexplored. We demonstrate that suppression of gut microbiota leads to increased levels of plasma and urinary aldosterone. These findings underscore the potential of the gut microbiota to influence aldosterone regulation, suggesting new possibilities for treating hypertension.

Correlation between plasma aldosterone concentration and bone mineral density in middle-aged and elderly hypertensive patients: potential impact on osteoporosis and future fracture risk

Background

Previous studies have suggested that aldosterone may play a major role in calcium-phosphorus homeostasis and bone metabolism. However, the relationship between plasma aldosterone concentrations (PAC) and bone mineral density (BMD) in middle-aged and elderly hypertensive patients remains unclear. Therefore, this study sought to investigate the relationship between PAC levels and BMD and explore PAC's potential impact on osteoporosis and future fracture risk in hypertensive patients.

Methods

Our study included a total of 1430 participants. Associations are tested using multiple linear and logistic regression models. Nonlinearity was investigated using the restricted cubic spline (RCS). We also performed mediating analyses to assess mediating factors mediating the relationship between PAC and osteoporosis.

Results

The multiple linear regression showed a negative correlation between PAC and BMD and was generally positively associated with FRAX scores. Meanwhile, logistic regression analyses indicated that osteoporosis was highly correlated with PAC levels. In addition, a clear non-linear dose-response relationship was also shown in the constructed RCS model. Finally, mediation analyses showed that serum potassium played an important role in the development of osteoporosis.

Conclusion

This study demonstrates that elevated PAC levels are strongly associated with decreased BMD, increased prevalence of osteoporosis, and the risk of future fractures in middle-aged and elderly hypertensive patients. Further studies are needed to confirm this relationship and reveal its underlying mechanisms.

Characteristics and Predictors of Apparent Treatment-Resistant Hypertension in Real-World Populations Using Electronic Health Record-Based Data

BACKGROUND

Apparent treatment-resistant hypertension (aTRH) is defined as uncontrolled blood pressure (BP) despite using ≥3 antihypertensive classes or controlled BP while using ≥4 antihypertensive classes. Patients with aTRH have a higher risk for adverse cardiovascular outcomes compared with patients with controlled hypertension (HTN). Although there have been prior reports on the prevalence, characteristics, and predictors of aTRH, these have been broadly derived from smaller datasets, randomized controlled trials, or closed healthcare systems.

METHODS

We extracted patients with HTN defined by ICD-9 and ICD-10 codes during 1/1/2015-12/31/2018, from 2 large electronic health record databases: the OneFlorida Data Trust (n = 223,384) and Research Action for Health Network (REACHnet) (n = 175,229). We applied our previously validated aTRH and stable controlled HTN computable phenotype algorithms and performed univariate and multivariate analyses to identify the prevalence, characteristics, and predictors of aTRH in these populations.

RESULTS

The prevalence of aTRH among patients with HTN in OneFlorida (16.7%) and REACHnet (11.3%) was similar to prior reports. Both populations had a significantly higher proportion of Black patients with aTRH compared with those with stable controlled HTN. aTRH in both populations shared similar significant predictors, including Black race, diabetes, heart failure, chronic kidney disease, cardiomegaly, and higher body mass index. In both populations, aTRH was significantly associated with similar comorbidities, when compared with stable controlled HTN.

CONCLUSIONS

In 2 large, diverse real-world populations, we observed similar comorbidities and predictors of aTRH as prior studies. In the future, these results may be used to improve healthcare professionals' understanding of aTRH predictors and associated comorbidities.

Adrenal Vein Sampling in the Management of Primary Aldosteronism: The Added Value of Intraprocedural Cortisol Assessment

Introduction

Primary aldosteronism is the most common cause of secondary hypertension. Adrenal vein sampling is the gold standard for subtyping primary aldosteronism. However, this procedure is technically challenging and often has a low success rate. Our center is one of the very few performing this technique in our country with an increasing experience.

Objective

The aim of this study was to evaluate the role of the cortisol intraprocedural assay in improving the performance of adrenal vein sampling.

Design

We enrolled all of the patients with primary aldosteronism that underwent adrenal vein sampling from February 2016 to April 2023. The cortisol intraprocedural assay was introduced in October 2021.

Methods

We enrolled a total of 50 adrenal vein samplings performed on 43 patients with the diagnosis of primary aldosteronism. In this sample, 19 patients and 24 patients underwent adrenal vein sampling before and after intraprocedural cortisol measurement, respectively. The procedure was repeated in seven patients (one before and six after intraprocedural cortisol measurement), given the unsuccess of the first exam. Selectivity of the adrenal vein sampling was assumed if the serum cortisol concentration from the adrenal vein was at least five times higher than that of the inferior vena cava. Lateralization was assumed if the aldosterone to cortisol ratio of one adrenal vein was at least four times the aldosterone to cortisol ratio of the contralateral side.

Results

The mean age of the patients that underwent adrenal vein sampling (N = 43) was 55.2 ± 8.9 years, and 53.5% (n = 23) were female. The mean interval between the diagnosis of hypertension and the diagnosis of primary aldosteronism was 9.8 years (±9.9). At diagnosis, 62.8% of the patients (n = 27) had hypokalemia (mean value of 3 mmol/L (±0.34)), 88.4% (n = 38) had adrenal abnormalities on preprocedural CT scan, and 67.4% (n = 29) described as unilateral nodules. There were no statistically significant differences in the patients' baseline characteristics between the two groups (before and after intraprocedural cortisol measurement). Before intraprocedural cortisol measurement, adrenal vein sampling selectivity was achieved in 35% (n = 7) patients. Selectivity increased to 100% (30/30) after intraprocedural cortisol measurement (p < 0.001). With the exception of one patient who refused it, all patients with lateralized disease underwent unilateral adrenalectomy with normalization of the aldosterone to renin ratio postoperatively.

Conclusions

The lack of effective alternatives in subtyping primary aldosteronism highlights the need to improve the success rate of adrenal vein sampling. In this study, intraprocedural cortisol measurement allowed a selectivity of 100%. Its addition to this procedure protocol should be considered, especially in centers with a low success rate.

Future treatments in hypertension: Can we meet the unmet needs of patients?

The prevalence of arterial hypertension is approximately 47% in the United States and 55% in Europe. Multiple different medical therapies are used to treat hypertension including diuretics, beta blockers, calcium channel blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors, alpha blockers, central acting alpha receptor agonists, neprilysin inhibitors and vasodilators. However, despite the numerous number of medications, the prevalence of hypertension is on the rise, a considerable proportion of the hypertensive population is resistant to these therapeutic modalities and a definitive cure is not possible with the current treatment approaches. Therefore, there is a need for novel therapeutic strategies to provide better treatment and control of hypertension. In this review, our aim is to describe the latest developments in the treatment of hypertension including novel medication classes, gene therapies and RNA-based modalities.

A flexible symbolic regression method for constructing interpretable clinical prediction models

Machine learning (ML) models trained for triggering clinical decision support (CDS) are typically either accurate or interpretable but not both. Scaling CDS to the panoply of clinical use cases while mitigating risks to patients will require many ML models be intuitively interpretable for clinicians. To this end, we adapted a symbolic regression method, coined the feature engineering automation tool (FEAT), to train concise and accurate models from high-dimensional electronic health record (EHR) data. We first present an in-depth application of FEAT to classify hypertension, hypertension with unexplained hypokalemia, and apparent treatment-resistant hypertension (aTRH) using EHR data for 1200 subjects receiving longitudinal care in a large healthcare system. FEAT models trained to predict phenotypes adjudicated by chart review had equivalent or higher discriminative performance (p < 0.001) and were at least three times smaller (p < 1 × 10^-6) than other potentially interpretable models. For aTRH, FEAT generated a six-feature, highly discriminative (positive predictive value = 0.70, sensitivity = 0.62), and clinically intuitive model. To assess the generalizability of the approach, we tested FEAT on 25 benchmark clinical phenotyping tasks using the MIMIC-III critical care database. Under comparable dimensionality constraints, FEAT's models exhibited higher area under the receiver-operating curve scores than penalized linear models across tasks (p < 6 × 10^-6). In summary, FEAT can train EHR prediction models that are both intuitively interpretable and accurate, which should facilitate safe and effective scaling of ML-triggered CDS to the panoply of potential clinical use cases and healthcare practices.

Characteristics and Predictors of Apparent Treatment Resistant Hypertension in Real-World Populations Using Electronic Health Record-Based Data

Background

Apparent treatment-resistant hypertension (aTRH) is defined as uncontrolled blood pressure (BP) despite using ≥3 antihypertensive classes or controlled BP while using ≥4 antihypertensive classes. Patients with aTRH have a higher risk for adverse cardiovascular outcomes compared to patients with controlled hypertension. Although there have been prior reports on the prevalence, characteristics, and predictors of aTRH, these have been broadly derived from smaller datasets, randomized controlled trials, or closed healthcare systems.

Methods

We extracted patients with hypertension defined by ICD 9 and 10 codes during 1/1/2015-12/31/2018, from two large electronic health record databases: the OneFlorida Data Trust (n=223,384) and Research Action for Health Network (REACHnet) (n=175,229). We applied our previously validated aTRH and stable controlled hypertension (HTN) computable phenotype algorithms and performed univariate and multivariate analyses to identify the prevalence, characteristics, and predictors of aTRH in these real-world populations.

Results

The prevalence of aTRH in OneFlorida (16.7%) and REACHnet (11.3%) was similar to prior reports. Both populations had a significantly higher proportion of black patients with aTRH compared to those with stable controlled HTN. aTRH in both populations shared similar significant predictors, including black race, diabetes, heart failure, chronic kidney disease, cardiomegaly, and higher body mass index. In both populations, aTRH was significantly associated with similar comorbidities, when compared with stable controlled HTN.

Conclusion

In two large, diverse real-world populations, we observed similar comorbidities and predictors of aTRH as prior studies. In the future, these results may be used to improve healthcare professionals' understanding of aTRH predictors and associated comorbidities.

Clinical Perspective

What Is New?: Prior studies of apparent treatment resistant hypertension have focused on cohorts from smaller datasets, randomized controlled trials, or closed healthcare systems.We used validated computable phenotype algorithms for apparent treatment resistant hypertension and stable controlled hypertension to identify the prevalence, characteristics, and predictors of apparent treatment resistant hypertension in two large, diverse real-world populations.What Are the Clinical Implications?: Large, diverse real-world populations showed a similar prevalence of aTRH, 16.7% in OneFlorida and 11.3% in REACHnet, compared to those observed from other cohorts.Patients classified as apparent treatment resistant hypertension were significantly older and had a higher prevalence of comorbid conditions such as diabetes, dyslipidemia, coronary artery disease, heart failure with preserved ejection fraction, and chronic kidney disease stages 1-3.Within diverse, real-world populations, the strongest predictors for apparent treatment resistant hypertension were black race, higher body mass index, heart failure, chronic kidney disease, and diabetes.

Online prediction model for primary aldosteronism in patients with hypertension in Chinese population: A two-center retrospective study

BACKGROUND

The prevalence of primary aldosteronism (PA) varies from 5% to 20% in patients with hypertension but is largely underdiagnosed. Expanding screening for PA to all patients with hypertension to improve diagnostic efficiency is needed. A novel and portable prediction tool that can expand screening for PA is highly desirable.

METHODS

Clinical characteristics and laboratory data of 1,314 patients with hypertension were collected for modeling and randomly divided into a training cohort (919 of 1,314, 70%) and an internal validation cohort (395 of 1,314, 30%). Additionally, an external dataset (n = 285) was used for model validation. Machine learning algorithms were applied to develop a discriminant model. Sensitivity, specificity, and accuracy were used to evaluate the performance of the model.

RESULTS

Seven independent risk factors for predicting PA were identified, including age, sex, hypokalemia, serum sodium, serum sodium-to-potassium ratio, anion gap, and alkaline urine. The prediction model showed sufficient predictive accuracy, with area under the curve (AUC) values of 0.839 (95% CI: 0.81-0.87), 0.814 (95% CI: 0.77-0.86), and 0.839 (95% CI: 0.79-0.89) in the training set, internal validation, and external validation set, respectively. The calibration curves exhibited good agreement between the predictive risk of the model and the actual risk. An online prediction model was developed to make the model more portable to use.

CONCLUSION

The online prediction model we constructed using conventional clinical characteristics and laboratory tests is portable and reliable. This allowed it to be widely used not only in the hospital but also in community health service centers and may help to improve the diagnostic efficiency of PA.

[Clinical value of captopril test in noninvasive diagnosis of aldosterone-producing adenoma]

OBJECTIVE

To analyze the clinical characteristics of aldosterone-producing adenoma (APA) subtypes in primary aldosteronism (PA) and the application value of captopril challenge test (CCT) in adenomas. And to find out the clinically specific non-invasive index for identifying APA subtypes from PA.

METHODS

The clinical data of hospitalized patients with hypertension were retrospectively collected. All the patients were conducted with the CCT and 90 patients with PA were confirmed. Among them, 34 patients were confirmed to have APA by surgery. The clinical indicators of the two groups of patients including plasma aldosterone concentration (PAC), aldosterone inhibition rate (%), and aldosterone to renin ratio (ARR) before and after the CCT were compared, the receiver operating characteristic (ROC) curves for the relevant indicators before and after the CCT drawn, and the areas under the curve (AUC) compared. The ROC curves were used to analyze the efficiency of the different CCT diagnostic criteria for diagnosing APA.

RESULTS

Compared with the PA group, the duration of hypertension was shorter, the incidence of hypokalemia was higher, and the average serum potassium level was lower when APA was diagnosed. There were no significant differences in blood pressure level, gender, serum sodium and body mass index between the two groups. Compared with PA population, APA group had higher PAC and ARR whether before or after the CCT, but lower plasma renin concentration (PRC). In APA patients, the mean degree of PAC declined after CCT was approximately 5.7%, but 5% with that of PA. As for diagnosing, ARR before or after CCT had diagnostic value for APA, in which the ARR cut-off point was 7.12, which yielded a sensitivity and specificity of 35.85% and 77.78%. The cut-off point of ARR after CCT was 4.23, with a sensitivity of 71.43% and specificity of 62.22%. For the diagnosis, the ARR before and after CCT were of no significant difference. However, the diagnostic specificity of ARR>7.12 combined with hypokalemia was up to 80%.

CONCLUSION

ARR before or after CCT have clinical value for the diagnosis of APA from PA, when combined with hypokalemia yielded high specificity.

Developing an ultra-performance liquid chromatography-tandem mass spectrometry for detecting aldosterone in human plasma

BACKGROUND

Accurately measuring plasma aldosterone concentration is difficult but meaningful for primary aldosteronism (PA) diagnosis.

METHODS

In this study, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for plasma aldosterone detection, evaluated its performance according to guidelines issued by CLSI, including detection limit, linearity, precision, and compared it with chemiluminescence immunoassay. Then, a reference range of plasma aldosterone in young people was established by using this method.

RESULTS

The lower limit of quantitation (LOQ) was 10 pg/ml. The mean recovery rates of analyte added to serum were 100.07-102.05% in different concentrations. The linearity range was 20-2000 pg/ml. Inter-assay CVs were 2.20-3.97% at aldosterone concentrations of 65.66-854.75 pg/ml. The regression equation of UPLC-MS/MS (x) and chemiluminescence immunoassay (y) was y = 1.002x + 65.854 (r = 0.9456, n = 237). The reference range of plasma aldosterone detected by UPLC-MS/MS was 11.30-363.82 pg/ml in young people in South China, and there was no statistically significant difference in plasma aldosterone concentration between two genders.

CONCLUSION

In conclusion, UPLC-MS/MS can rapidly and accurately detect plasma aldosterone and is appropriate for clinical application.

Aldosterone-producing adenoma-harbouring KCNJ5 mutations is associated with lower prevalence of metabolic disorders and abdominal obesity

OBJECTIVE

Aldosterone overproduction and lipid metabolic disturbances between idiopathic hyperaldosteronism (IHA) and unilateral aldosterone-producing adenoma (APA) have been inconsistently linked in patients with primary aldosteronism. Moreover, KCNJ5 mutations are prevalent among APAs and enhance aldosterone synthesis in adrenal cortex. We aimed to investigate the prevalence of metabolic syndrome (MetS) in each primary aldosteronism subtype and observe the role of KCNJ5 mutations among APAs on the distribution of abdominal adipose tissues quantified using computed tomography (CT), including their changes postadrenalectomy.

DESIGN AND METHODS

We retrospectively collected 244 and 177 patients with IHA and APA at baseline. Patients with APA had undergone adrenalectomy, and gene sequencing revealed the absence (n = 75) and presence (n = 102) of KCNJ5 mutations. We also recruited 31 patients with APA who had undergone CT-scan 1-year postadrenalectomy.

RESULTS

The patients with APA harbouring KCNJ5 mutations had significantly lower prevalence of MetS and smaller distribution in waist circumference, subcutaneous adipose tissue (SAT), and visceral adipose tissue (VAT) than the other groups. Logistic regression analysis indicated that the VAT area correlated significantly with KCNJ5 mutations among the APAs. Only participants with KCNJ5 mutations had significant increases in triglycerides, cholesterol, SAT, and VAT after 1-year postadrenalectomy.

CONCLUSION

This study is the first to demonstrate that MetS and abdominal obesity were less prevalent in the patients with APA harbouring KCNJ5 mutations compared with the IHA group and the non-KCNJ5-mutated APA group. Increasing prevalence of dyslipidaemia and abdominal obesity was observed in patients with KCNJ5 mutations 1-year postadrenalectomy.

Outcomes of a Specialized Clinic on Rates of Investigation and Treatment of Primary Aldosteronism

Importance

Primary aldosteronism (PA) is one of the most common causes of secondary hypertension but remains largely unrecognized and untreated.

Objective

To understand the outcomes of a specialized clinic on rates of evaluation and treatment of PA in the context of secondary factors.

Design, Setting, and Participants

This population-based cohort study was conducted in Alberta, Canada, using linked administrative data between April 1, 2012, and July 31, 2019, on adults identified as having hypertension.

Main Outcomes and Measures

We evaluated each step of the diagnostic and care pathway for PA to determine the proportion of people with hypertension who received screening, subtyping, and targeted treatment for PA. Variations in diagnosis and treatment were examined according to individual-level, clinician-level, and system-level characteristics.

Results

Of the 1.1 million adults with hypertension, 7941 people (0.7%) were screened for PA. Among those who were screened, 1703 (21.4%) had positive test results consistent with possible PA, and 1005 (59.0%) of these were further investigated to distinguish between unilateral and bilateral forms of PA. Only 731 individuals (42.9%) with a positive screen result received disease-targeted treatment. Geographic zones and clinician specialty were the strongest determinants of screening, subtyping, and treatment of PA, with the highest rates corresponding to the location of the provincial endocrine hypertension program.

Conclusions and Relevance

In this cohort, less than 1% of patients expected to have PA were ever formally diagnosed and treated. These findings suggest that a system-level approach to assist with investigation and treatment of PA may be highly effective in closing care gaps and improving clinical outcomes.

Aldosterone, Inflammation, Immune System, and Hypertension

Aldosterone is a mineralocorticoid hormone that controls body fluid and electrolyte balance. Excess aldosterone is associated with cardiovascular and metabolic diseases. Inflammation plays a critical role on vascular damage promoted by aldosterone and aggravates vascular abnormalities, including endothelial dysfunction, vascular remodeling, fibrosis and oxidative stress, and other manifestations of end-organ damage that are associated with hypertension, other forms of cardiovascular disease, and diabetes mellitus and the metabolic syndrome. Over the past few years, many studies have consistently shown that aldosterone activates cells of the innate and adaptive immune systems. Macrophages and T cells accumulate in the kidneys, heart, and vasculature in response to aldosterone, and infiltration of immune cells contributes to end-organ damage in cardiovascular and metabolic diseases. Aldosterone activates various subsets of innate immune cells such as dendritic cells and monocytes/macrophages, as well as adaptive immune cells such as T lymphocytes, and, by activation of mineralocorticoid receptors stimulates proinflammatory transcription factors and the production of adhesion molecules and inflammatory cytokines and chemokines. This review will briefly highlight some of the studies on the involvement of aldosterone in activation of innate and adaptive immune cells and its impact on the cardiovascular system. Since aldosterone plays a key role in many cardiovascular and metabolic diseases, these data will open up promising perspectives for the identification of novel biomarkers and therapeutic targets for prevention and treatment of diseases associated with increased levels of aldosterone, such as arterial hypertension, obesity, the metabolic syndrome, and heart failure.

Surgical Outcomes of Aldosterone-Producing Adenoma on the Basis of the Histopathological Findings

INTRODUCTION

Previous studies on the surgical outcomes of aldosterone-producing adenoma (APA) patients were mainly based on the histopathological diagnosis of HE staining or adrenal venous sampling (AVS) instead of the functional pathology. The aim of the present study was to evaluate the surgical outcomes of APA patients based on the functional pathological diagnosis of APA according to HISTALDO (histopathology of primary aldosteronism) consensus.

METHODS

Clinical data of 137 patients with suspected APA were analyzed retrospectively. All patients had hypertension and spontaneous hypokalemia. In all patients, CT showed a unilateral solitary hypodense adrenal lesion, and a contralateral adrenal gland of normal morphology. Tumors were removed and immunostained for CYP11B2, and their pathology were identified based on HISTALDO consensus. Patients were followed up 6 to 24 months after operation.

RESULTS

Among 137 cases of presumptive APA diagnosed by CT, 130 (95%) cases were pathologically diagnosed with classical pathology, including 123 APA(90%) and 7 aldosterone-producing nodule (APN) (5%). 7 cases (5%) had non-functioning adenoma (NFA) with aldosterone-producing micronodule (APM) or multiple aldosterone-producing micronodule (MAPM) in the surrounding adrenal tissue. In all 137 patients, hypertension was complete or partial clinical success postoperatively. Complete clinical success was achieved in 73 (53%), and partial clinical success was achieved in 64 (47%) cases. Serum potassium level recovered to normal in all. In 123 patients with APA, complete clinical success was reached in 67 (54%), and partial clinical success was reached in 56 (46%) cases. Gender, duration of hypertension and the highest SBP were significant independent predictors for cure of APA after surgery. A multiple logistic regression model integrating the three predictors was constructed to predict the outcome, which achieved a sensitivity of 72.4% and a specificity of 73.1%.

CONCLUSION

The specificity of CT in the diagnosis of APA and APN patients with hypokalemia was 95%. All patients achieved complete or partial clinical success after surgery. Gender, duration of hypertension and the highest SBP were independent predictors for the postoperative cure of APA.

Feasibility of a Clinical Decision Support Tool to Manage Resistant Hypertension: Team-HTN, a Single-arm Pilot Study

INTRODUCTION

Based on defining criteria, hypertension (HTN) affects 31% to 46% of the adult U.S. population and almost 20% of service members. Resistant HTN (rHTN) consumes significant resources, carries substantial morbidity and mortality risk and costs over $350 billion dollars annually. For multiple reasons, only 48.3% of people with HTN are controlled, e.g., undiagnosed secondary HTN, therapeutic or diagnostic inertia, and patient adherence. Our purpose was to determine the feasibility of a web-based clinical decision support tool (CDST) using a renin-aldosterone system (RAS) classification matrix and drug sequencing algorithm to assist providers with the diagnosis and management of uncontrolled HTN (rHTN). Outcomes were blood pressure (BP) rates of control, provider management time, and end-user satisfaction.

METHODS

This two-phase, prospective, non-randomized, single-arm, six-month pilot study was conducted in primary care clinics at a tertiary military medical center. Patients with uncontrolled HTN and primary care providers were recruited. Phase 1 patients checked their BP twice daily (AM and PM), three times weekly using a standardized arm cuff. Patients with rHTN were enrolled in phase 2. Phase 2 patients were managed virtually by providers using the CDST, the RAS classification matrix, and the drug sequencing algorithm which incorporated age, ethnicity, comorbidities, and renin/aldosterone levels. Medications were adjusted every 10 days until BP was at target, using virtual visits.

RESULTS

In total, 54 patients and 16 providers were consented. One transplant patient was disqualified, 29 met phase 2 criteria for rHTN, and 6 providers completed the study. In phase 1, 45% (n = 24) of patients were identified as having apparent uncontrolled HTN using peak diurnal blood pressure (pdBP) home readings. In phase 2 (n = 29), previously undetected RAS abnormalities were identified in 69% (n = 20) of patients. Blood pressure control rates improved from 0% to 23%, 47%, and 58% at 2, 4, and 6 months, respectively. Provider management time was reduced by 17%. Using home pdBP readings identified masked HTN in almost 20% of patients that would have been missed by a single daily AM or PM home BP measurement. Feasibility and satisfaction trends were favorable.

CONCLUSIONS

Despite significant morbidity, mortality, and existing guidelines, over half of hypertensive patients are uncontrolled. Our results suggest that this CDST used with pdBP monitoring is a feasible option to facilitate improved rates of control in rHTN, aid in overcoming therapeutic/diagnostic inertia, improve identification of secondary HTN, and potentially, access. Further research with this tool in a larger population is recommended.

Comparison of three different chemiluminescence assays and a rapid liquid chromatography tandem mass spectrometry method for measuring serum aldosterone

Background This study aimed to quantify and compare serum aldosterone (sALD) levels through three different chemiluminescence immunoassays (CLIAs) and liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Methods Serum samples from 221 patients with suspected primary aldosteronism (PA) were retrospectively included in this study conducted at the Peking Union Medical College Hospital from June to August in 2017. sALD levels were determined using the LC-MS/MS method and three different CLIA systems, viz., DiaSorin® XL, iSYS and Auto Lumo A2000. Pooled fresh serum samples were used for recalibration. Passing-Bablok regression analysis, correlation matrix, and Bland-Altman plots were used to evaluate the concurrence among ALD levels determined using the three CLIAs. Results Within-laboratory precision of the four assays ranged from 2.1% to 9.4%, except the coefficient variation (CV) of one of the CLIAs, which exceeded 20.0% for samples with low sALD levels. sALD levels determined using LC-MS/MS were significantly lower than those determined using the other three CLIAs (p < 0.0001). Spearman's correlation coefficient of the four assays ranged from 0.745 to 0.950 (p < 0.0001). The Bland-Altman plot showed that the average bias (%) for the three CLIAs and LC-MS/MS ranged from -69.3 to -49.2. After recalibration, this correlation did not improve among the assays. However, the bias and bias percentage at the medical decision level improved between LC-MS/MS and DiaSorin® XL/iSYS. Conclusions Significant inconsistencies between the results of CLIAs and LC-MS/MS indicate that different sALD measures cannot be used interchangeably.

High Efficiency and Problems of Chemiluminescence Assay-Detected Aldosterone-To-Renin Ratio in Practical Primary Aldosteronism Screening

Primary aldosteronism is a main cause of secondary hypertension which can be effectively treated. The screening test for primary aldosteronism is benefit for minimizing damage to the patient. In the previous retrospective study, we obtained the optimal cutoff value of aldosterone-to-renin ratio detected by chemiluminescence assay, a newly developing method, and prompted its high efficiency in primary aldosteronism screening in upright position. In this study, we want to evaluate its efficiency in practical work. We used this ratio to continuously screen 238 patients, and 58 patients were finally diagnosed with primary aldosteronism. We found it had 86.13% accuracy rate in the upright position compared with the final clinical diagnosis. False negative and positive rates were 13.79% and 13.89%. Diagnostic sensitivity and specificity were 86.21% and 86.11%, which are slightly different from results in our previous study. False negative rate can be improved by combining the aldosterone-to-renin ratio with aldosterone concentration. We also found impaired glucose tolerance may be a reason for high false positive rate. Besides, chemiluminescence assay may be interfered in aldosterone detection. Although it has some shortcomings, chemiluminescence assay-detected aldosterone-to-renin ratio is a highly effective index for screening primary aldosteronism in practice.

Unilateral Disease Is Common in Patients With Primary Aldosteronism Without Adrenal Nodules

BACKGROUND

Patients with primary aldosteronism (PA) without apparent adrenal nodularity have not been well characterised in the literature. The aim of this study was to assess for unilateral aldosterone hypersecretion among patients with primary aldosteronism with normal-appearing adrenals using adrenal vein sampling (AVS).

METHODS

In this cross-sectional study performed at a Canadian tertiary care centre, we reviewed all consecutive PA patients lacking a definitive adrenal nodule who were referred for AVS in the work-up of PA between January 2006 and May 2018. AVS indications included an elevated aldosterone-to-renin ratio and high-probability features of PA.

RESULTS

In total, 174 patients were included (mean age, 52.0 years; 62.6% male), and 70 (40.2%) had unilateral aldosterone hypersecretion. There was a positive linear association between higher age categories (by decade) and lateralisation (P = 0.03). For every decade of age, there was a 30% higher odds of lateralisation (odds ratio, 1.03 per year; 95% confidence interval, 1.00-1.05). The frequency of lateralisation was higher in males compared with females (47.7% vs 27.7%), with a 2-fold greater odds of unilateral disease (odds ratio, 2.38; 95% confidence interval, 1.23-4.61). Traditional biomarkers of lateralisation among patients with adrenal nodules (eg, serum potassium and aldosterone-to-renin ratio levels) were not predictive of lateralisation in this population.

CONCLUSIONS

Many patients with PA who lack definitive adrenal nodules have lateralising disease. Efforts to optimise referrals for AVS may be prioritised by focusing on patients most likely to have unilateral disease, especially males and older adults.

The Quality of Clinical Practice Guidelines and Consensuses on the Management of Primary Aldosteronism: A Critical Appraisal

Background: Several guidelines and expert consensuses have been developed for management of primary aldosteronism (PA). It is important to understand the detailed recommendations and quality of these guidelines to help physicians make informed and reliable decision.

Methods: PubMed, EMBASE, and three websites were searched for practice guidelines or consensuses of PA from inception to January 24, 2019. We summarized the major recommendations on the management of PA from these guidelines and consensuses. The Appraisal of Guidelines for Research and Evaluation II was used to assess quality of the included guidelines and consensuses.

Results: We identified three clinical practice guidelines and three consensus statements. Most of the recommendations on the diagnosis and treatment of PA from these guidelines and consensuses were consistent. Some minor conflicts were recorded for patient's screen and confirmation test. All included guideline documents have a good quality (score, >70%) on the scope and purpose (mean score, 81.02%) and clarity of presentation of the recommendations (mean score, 86.88%). However, the reporting for the stakeholder involvement (mean score, 54.32%) and applicability (mean score, 47.92%) were insufficient. There was an insufficient rigorousness in most of the guideline documents (mean score, 45.56%) on the development process. The Endocrine Society practice guideline 2016 ranked highest in quality (score, 81.13%).

Conclusions: Existing guideline documents provided valuable recommendations on the management of PA, but further efforts are needed to improve the methodological quality. The Endocrine Society practice guideline 2016 was recommended for use.

Associations between primary aldosteronism and diabetes, poor bone health, and sleep apnea-what do we know so far?

Primary aldosteronism (PA), the most common cause of secondary hypertension, is a well-recognized condition that can lead to cardiovascular and renal complications. PA is frequently left undiagnosed and untreated, leading to aldosterone-specific morbidity and mortality. In this review we highlight the evidence linking PA with other conditions such as (i) diabetes mellitus, (ii) obstructive sleep apnea, and (iii) bone health, along with clinical implications and proposed underlying mechanisms.

Endothelin: 30 Years From Discovery to Therapy

Discovered in 1987 as a potent endothelial cell-derived vasoconstrictor peptide, endothelin-1 (ET-1), the predominant member of the endothelin peptide family, is now recognized as a multifunctional peptide with cytokine-like activity contributing to almost all aspects of physiology and cell function. More than 30 000 scientific articles on endothelin were published over the past 3 decades, leading to the development and subsequent regulatory approval of a new class of therapeutics-the endothelin receptor antagonists (ERAs). This article reviews the history of the discovery of endothelin and its role in genetics, physiology, and disease. Here, we summarize the main clinical trials using ERAs and discuss the role of endothelin in cardiovascular diseases such as arterial hypertension, preecclampsia, coronary atherosclerosis, myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) caused by spontaneous coronary artery dissection (SCAD), Takotsubo syndrome, and heart failure. We also discuss how endothelins contributes to diabetic kidney disease and focal segmental glomerulosclerosis, pulmonary arterial hypertension, as well as cancer, immune disorders, and allograft rejection (which all involve ET_A autoantibodies), and neurological diseases. The application of ERAs, dual endothelin receptor/angiotensin receptor antagonists (DARAs), selective ET_B agonists, novel biologics such as receptor-targeting antibodies, or immunization against ET_A receptors holds the potential to slow the progression or even reverse chronic noncommunicable diseases. Future clinical studies will show whether targeting endothelin receptors can prevent or reduce disability from disease and improve clinical outcome, quality of life, and survival in patients.

Application of strict criteria in adrenal venous sampling increases the proportion of missed patients with unilateral disease who benefit from surgery for primary aldosteronism

OBJECTIVES

Adrenal vein sampling (AVS) is intended to confirm unilateral forms of primary aldosteronism, which are amenable to surgical cure. Excessively strict AVS criteria to define lateralization may result in many patients incorrectly categorized as bilateral primary aldosteronism and opportunity for surgical cure missed.

METHODS

Retrospective review of an AVS-primary aldosteronism database in which surgical cases are verified by standardized outcomes. Having used 'less strict' AVS criteria for lateralization, we examined the distribution of AVS lateralization indices in our confirmed unilateral primary aldosteronism cases both with and without cosyntropin stimulation. The proportion of proven unilateral cases that would have been missed with stricter AVS interpretation criteria was calculated. Particular focus was given to the proportion of missed cases according to use of international guidelines. False-positive lateralization with 'less strict' interpretation was also calculated.

RESULTS

Of 80 surgical primary aldosteronism cases, 10-23% would have been missed with AVS lateralization indices of 3 : 1 to 5 : 1, with or without cosyntropin. If strict selectivity indices (for confirmation of catheterization) were combined with strict lateralization indices, up to 70% of unilateral primary aldosteronism cases could have been missed. Use of Endocrine Society AVS guidelines would have missed 21-43% of proven unilateral cases. 'Less strict' AVS interpretation yielded one case (1.2%) of false lateralization.

CONCLUSION

Excessively strict AVS interpretation criteria will result in a high rate of missed unilateral primary aldosteronism with subsequent loss of opportunity for intervention. Use of more lenient lateralization criteria will improve the detection rate of unilateral primary aldosteronism with very low false-positive rate.

Discordance Between Imaging and Adrenal Vein Sampling in Primary Aldosteronism Irrespective of Interpretation Criteria

BACKGROUND

Subtyping of primary aldosteronism (PA) using imaging and adrenal vein sampling (AVS) may yield discordant results, causing confusion in management. Interpretation criteria for AVS lateralization may affect discordance rates.

METHODS

We identified consecutive patients with PA who underwent AVS at a quaternary care center between January 2006 and May 2018. Patient demographics, laboratory results, diagnostic imaging, and AVS results were retrieved. Adrenal cross-sectional imaging was compared with AVS findings. The presence of lateralization was defined using varying thresholds for the lateralization index (LI) from >2:1 to >5:1. Discordance was defined by a unilateral lesion on imaging with contralateral or nonlateralization on AVS.

RESULTS

A total of 342 patients were included; 68.7% had hypokalemia. With cross-sectional imaging, 191 (55.6%) patients had unilateral lesions, 47 (13.7%) had bilateral lesions, and 104 (30.4%) had normal imaging. Overall discordance rates were high, ranging from 22% to 28% for LI thresholds of >2:1 and >5:1, respectively. Discordance between imaging and AVS was positively correlated with LI threshold stringency (P < 0.001). Patients with normal or bilateral lesions on imaging frequently lateralized on AVS. Lateralization, when present, was approximately equal between left and right sides, irrespective of the LI threshold.

CONCLUSIONS

Discrepancies between imaging and AVS were common, even among patients with nonspecific imaging. Discordance was greatest with the strictest AVS interpretation criteria. Even under the most lenient thresholds, apparent discordance between imaging and AVS exceeded 20% and may limit the ability to make surgical decisions. Reliance on imaging alone for detecting lateralization may be misleading.

Vascular Mineralocorticoid Receptor: Evolutionary Mediator of Wound Healing Turned Harmful by Our Modern Lifestyle

The mineralocorticoid receptor (MR) is indispensable for survival through its critical role in maintaining blood pressure in response to sodium scarcity or bleeding. Activation of MR by aldosterone in the kidney controls water and electrolyte homeostasis. This review summarizes recent advances in our understanding of MR function, specifically in vascular endothelial and smooth muscle cells. The evolving roles for vascular MR are summarized in the areas of (i) vascular tone regulation, (ii) thrombosis, (iii) inflammation, and (iv) vascular remodeling/fibrosis. Synthesis of the data supports the concept that vascular MR does not contribute substantially to basal homeostasis but rather, MR is poised to be activated when the vasculature is damaged to coordinate blood pressure maintenance and wound healing. Specifically, MR activation in the vascular wall promotes vasoconstriction, inflammation, and exuberant vascular remodeling with fibrosis. A teleological model is proposed in which these functions of vascular MR may have provided a critical evolutionary survival advantage in the face of mechanical vascular injury with bleeding. However, modern lifestyle is characterized by physical inactivity and high fat/high sodium diet resulting in diffuse vascular damage. Under these modern conditions, diffuse, persistent and unregulated activation of vascular MR contributes to post-reproductive cardiovascular disease in growing populations with hypertension, obesity, and advanced age.

Progress in the Management of Primary Aldosteronism

Primary aldosteronism (PA) is now considered as one of leading causes of secondary hypertension, accounting for 5-10% of all hypertensive patients and more strikingly 20% of those with resistant hypertension. Importantly, those with the unilateral disease could be surgically cured when diagnosed appropriately. On the other hand, only a very limited portion of those suspected to have PA has been screened, diagnosed, or treated to date. With current advancement in medical technologies and genetic research, expanding knowledge of PA has been accumulated and recent achievements have also been documented in the care of those with PA. This review is aimed to have focused description on updated topics of the following; importance of PA screening both in the general and specialized settings and careful interpretation of screening data, recent achievements in hormone assays and sampling methods and their clinical relevance, and expanding knowledge on PA genetics. Improvement in workup processes and novel treatment options, as well as better understanding of the PA pathogenesis based on genetic research, might be expected to result in increased cure and better care of the patients.