Serum Aldosterone Concentration, Blood Pressure, and Coronary Artery Calcium: The Multi-Ethnic Study of Atherosclerosis

Primary Aldosteronism and Risk of Cardiovascular Outcomes: Genome-Wide Association and Mendelian Randomization Study

BACKGROUND

Observational studies have reported associations between primary aldosteronism (PA) and cardiovascular outcomes, including coronary artery diseases (CAD), congestive heart failure (CHF), and stroke. However, establishing causality remains a challenge due to the lack of randomized controlled trial data on this topic. We thus aimed to investigate the causal relationship between PA and the risk of developing CAD, CHF, and stroke.

METHODS AND RESULTS

Cross-ancestry meta-analysis of genome-wide association studies combining East Asian and European ancestry (1560 PA cases and 742 139 controls) was conducted to identify single-nucleotide variants that are associated with PA. Then, using the identified genetic variants as instrumental variables, we conducted the 2-sample Mendelian randomization analysis to investigate the causal relationship between PA and incident CAD, CHF, and stroke among both East Asian and European ancestry. Summary association results were extracted from large genome-wide association studies consortia. Our cross-ancestry meta-analysis of East Asian and European populations identified 7 genetic loci significantly associated with the risk of PA, for which the genes nearest to the lead variants were CASZ1, WNT2B, HOTTIP, LSP1, TBX3, RXFP2, and NDP. Among the East Asian population, the pooled odds ratio estimates using these 7 genetic instruments of PA were 1.07 (95% CI, 1.03-1.11) for CAD, 1.10 (95% CI, 1.01-1.20) for CHF, and 1.13 (95% CI, 1.09-1.18) for stroke. The results were consistent among the European population.

CONCLUSIONS

Our 2-sample Mendelian randomization study revealed that PA had increased risks of CAD, CHF, and stroke. These findings highlight that early and active screening of PA is critical to prevent future cardiovascular events.

Aldosterone is Associated With New-onset Cerebrovascular Events in Patients With Hypertension and White Matter Lesions: A Cohort Study

OBJECTIVE

White matter lesions (WMLs) increase the risk of stroke, stroke recurrence, and death. Higher plasma aldosterone concentration (PAC) increases the risk of stroke, acute myocardial infarction, and hypertension. The objective is to evaluate the relationship between PAC and cerebrovascular events in patients with hypertension and WMLs.

METHODS

We conducted a retrospective cohort study that included 1041 participants hospitalized. The outcome was new-onset cerebrovascular events including intracerebral hemorrhage and stroke. A Cox regression model was used to evaluate the relationship between baseline PAC and the risk of cerebrovascular events.

RESULTS

The mean age of participants was 60.9 ± 10.2 years and 565 (53.4%) were males. The median follow-up duration was 42 months (interquartile range: 25-67), and 92 patients experienced new-onset cerebrovascular events. In a multivariate-adjusted model, with PAC as a continuous variable, higher PAC increased the risk of cerebrovascular events; patient risk increased per 1 (hazard ratio [HR: 1.03], 95% confidence interval [CI]: 1.01-1.06, P < .01), per 5 (HR: 1.17, 95% CI: 1.06-1.31, P < .01), and per 10 ng/dL (HR: 1.41, 95%: 1.14-1.75, P < .01) increase in PAC. When PAC was expressed as a categorical variable (quartile: Q1-Q4), patients in Q4 (HR: 2.12, 95% CI: 1.18-3.79, P < .05) exhibited an increased risk of cerebrovascular events compared to Q1. Restrictive spline regression showed a linear association between PAC and the risk of new-onset cerebrovascular events after adjusting for all possible variables.

CONCLUSIONS

Our study identified a linear association between PAC and the risk of new-onset cerebrovascular events in patients with hypertension and WMLs.

Cardiovascular Outcomes of KCNJ5 Mutated Aldosterone-Producing Adenoma: A Systematic Review

BACKGROUND

While clinical features of KCNJ5-mutated aldosterone-producing adenoma (APA) have been reported, evidence of its clinical outcomes is lacking. We aimed to synthesize available literature about the associations between KCNJ5 mutation with cardiovascular and metabolic outcomes among patients with APA.

METHODS

In this systematic review of observational studies, MEDLINE and Embase were searched through August 2022. Two independent authors screened the search results and extracted data from eligible observational studies investigating cardiovascular or metabolic outcomes between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs. Risk of Bias In Non-randomized Studies of Interventions was used to assess the quality of the included studies.

RESULTS

A total of 573 titles/abstracts were screened and after the expert opinion of the literature, full text was read in 20 titles/abstracts, of which 12 studies were included. Across 3 studies comparing the baseline or change in the cardiac function between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs, all studies reported the association between impaired cardiac functions and KCNJ5 mutation status. Among 6 studies evaluating the cure of hypertension after surgery, all studies showed that KCNJ5 mutation was significantly associated with the cure of hypertension. In quality assessment, 7 studies were at serious risk of bias, while the remaining studies were at moderate risk of bias.

CONCLUSIONS

This systematic review provided evidence of the significant association between KCNJ5 mutation and unfavorable cardiovascular outcomes in patients with primary aldosteronism. Further research is needed to improve the quality of evidence on this topic and elucidate the underlying mechanisms of the potential burden of KCNJ5 mutation.

Recent progress in unraveling cardiovascular complications associated with primary aldosteronism: a succinct review

This comprehensive review offers a thorough exploration of recent advancements in our understanding of the intricate cardiovascular complications associated with Primary Aldosteronism (PA). PA encompasses a spectrum of conditions characterized by hypertension and excessive production of aldosterone operating independently of the renin-angiotensin system. Given its association with an elevated risk of cardiovascular and cerebrovascular complications, as well as a higher incidence of metabolic syndrome in comparison to individuals with essential hypertension (EH), an accurate diagnosis of PA is of paramount importance. This review delves into the intricate interplay between PA and cardiovascular health and focuses on the key pathophysiological mechanisms contributing to adverse cardiac outcomes. The impact of different treatment modalities on cardiovascular health is also examined, offering insights into potential therapeutic approaches. By highlighting the significance of recognizing PA as a significant contributor to cardiovascular morbidity, this review emphasizes the need for improved screening, early diagnosis, and tailored management strategies to both enhance patient care and mitigate the burden of cardiovascular diseases. The findings presented herein underscore the growing importance of PA in the context of cardiovascular medicine and emphasize the potential for translating these insights into targeted interventions to improve patient outcomes.

Adverse Effects of Aldosterone: Beyond Blood Pressure

Aldosterone is a steroid hormone that primarily acts through activation of the mineralocorticoid receptor (MR), a nuclear receptor responsible for downstream genomic regulation. Classically, activation of the MR in the renal tubular epithelium is responsible for sodium retention and volume expansion, raising systemic blood pressure. However, activation of the MR across a wide distribution of tissue types has been implicated in multiple adverse consequences for cardiovascular, cerebrovascular, renal, and metabolic disease, independent of blood pressure alone. Primary aldosteronism, heart failure, and chronic kidney disease are states of excessive aldosterone production and MR activity where targeting MR activation has had clinical benefits out of proportion to blood pressure lowering. The growing list of established and emerging therapies that target aldosterone and MR activation may provide new opportunities to improve clinical outcomes and enhance cardiovascular and renal health.

Unilateral Primary Aldosteronism: Long-Term Disease Recurrence After Adrenalectomy

BACKGROUND

Primary aldosteronism (PA) is frequently caused by a unilateral aldosterone-producing adenoma with a PA-driver mutation. Unilateral adrenalectomy has a high probability of short-term biochemical remission, but long-term postsurgical outcomes are relatively undefined. Our objective was to investigate the incidence of long-term recurrence of PA in individuals with postsurgical short-term biochemical remission.

METHODS

Adrenalectomized patients for unilateral PA were included from a single referral center. Histopathology and outcomes were assessed according to international histopathology of unilateral primary aldosteronism and PASO (Primary Aldosteronism Surgical Outcome) consensuses. Genotyping was performed using CYP11B2 (aldosterone synthase)-guided sequencing.

RESULTS

Classical adrenal histopathology, exemplified by a solitary aldosterone-producing adenoma, was observed in 78% of 90 adrenals, compared with 22% with nonclassical histopathology. The classical group displayed higher aldosterone-to-renin ratios (P=0.013) and lower contralateral ratios (P=0.008). Outcome assessments at both short (12 months [7; 12]) and long (89 months [48; 124]) terms were available for 57 patients. At short-term assessment, 53 (93%) displayed complete biochemical success (43 classical and 10 nonclassical), but long-term assessment demonstrated biochemical PA recurrence in 12 (23%) with an overrepresentation of the nonclassical histopathology (6 [60%] of 10 nonclassical histopathology versus 6 [14%] of 43 classical histopathology; P=0.005). PA-driver mutations were identified in 97% of 64 aldosterone-producing adenomas; there was no association of the aldosterone-producing adenoma genotype with PA recurrence.

CONCLUSIONS

A substantial proportion of individuals display postsurgical biochemical recurrence of PA, which is related to the histopathology of the resected adrenal gland. These findings emphasize the role of histopathology and the requirement for continued outcome assessment in the management of surgically treated patients for PA.

Association of the trajectory of plasma aldosterone concentration with the risk of cardiovascular disease in patients with hypertension: a cohort study

The purpose of this study was to determine the long-term pattern of plasma aldosterone concentration (PAC) trajectories and to explore the relationship between PAC trajectory patterns and cardiovascular disease (CVD) risk in patients with hypertension. Participants were surveyed three times between 2010 and 2016, and latent mixed modeling was employed to determine the trajectory of PAC over the exposure period (2010-2016). A Cox regression analysis was used to examine the association between PAC trajectory patterns and the risk of CVD (stroke and myocardial infarction). Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were calculated and reported. During a median follow-up of 4.10 (3.37-4.50) years, 82 incident CVD cases (33 myocardial infarction cases and 49 stroke cases) were identified. Among all three PAC models, the high-stability PAC pattern exhibited the highest risk of CVD. After full adjustment for all covariables, HRs were 2.19 (95% CI 1.59-3.01) for the moderate-stable pattern and 2.56 (95% CI 1.68-3.91) for the high-stable pattern in comparison to the low-stable pattern. Subgroup and sensitivity analyses verified this association. The presence of a high-stable PAC trajectory pattern is associated with an elevated risk of CVD in hypertensive patients. Nevertheless, more studies are warranted to confirm these findings.

Subclinical Primary Aldosteronism and Cardiovascular Health: A Population-Based Cohort Study

BACKGROUND

Primary aldosteronism, characterized by overt renin-independent aldosterone production, is a common but underrecognized form of hypertension and cardiovascular disease. Growing evidence suggests that milder and subclinical forms of primary aldosteronism are highly prevalent, yet their contribution to cardiovascular disease is not well characterized.

METHODS

This prospective study included 1284 participants between the ages of 40 and 69 years from the randomly sampled population-based CARTaGENE cohort (Québec, Canada). Regression models were used to analyze associations of aldosterone, renin, and the aldosterone-to-renin ratio with the following measures of cardiovascular health: arterial stiffness, assessed by central blood pressure (BP) and pulse wave velocity; adverse cardiac remodeling, captured by cardiac magnetic resonance imaging, including indexed maximum left atrial volume, left ventricular mass index, left ventricular remodeling index, and left ventricular hypertrophy; and incident hypertension.

RESULTS

The mean (SD) age of participants was 54 (8) years and 51% were men. The mean (SD) systolic and diastolic BP were 123 (15) and 72 (10) mm Hg, respectively. At baseline, 736 participants (57%) had normal BP and 548 (43%) had hypertension. Higher aldosterone-to-renin ratio, indicative of renin-independent aldosteronism (ie, subclinical primary aldosteronism), was associated with increased arterial stiffness, including increased central BP and pulse wave velocity, along with adverse cardiac remodeling, including increased indexed maximum left atrial volume, left ventricular mass index, and left ventricular remodeling index (all P<0.05). Higher aldosterone-to-renin ratio was also associated with higher odds of left ventricular hypertrophy (odds ratio, 1.32 [95% CI, 1.002-1.73]) and higher odds of developing incident hypertension (odds ratio, 1.29 [95% CI, 1.03-1.62]). All the associations were consistent when assessing participants with normal BP in isolation and were independent of brachial BP.

CONCLUSIONS

Independent of brachial BP, a biochemical phenotype of subclinical primary aldosteronism is negatively associated with cardiovascular health, including greater arterial stiffness, adverse cardiac remodeling, and incident hypertension.

Unilateral chemical ablation of the adrenal gland lowers blood pressure and alleviates target organ damage in spontaneously hypertensive rats

Adrenal gland hormones play a critical role in the development and maintenance of hypertension. Adrenal ablation has been used to treat primary aldosteronism but not essential hypertension. The present study aimed to investigate the effectiveness and safety of unilateral adrenal gland ablation in treating spontaneously hypertensive rats (SHR). SHR and Wistar-Kyoto rats (WKY) were subjected to unilateral adrenal ablation with injection of anhydrous ethanol or a sham procedure. Blood pressure was monitored by both tail-cuff plethysmography and telemetry until 6 months after the procedure. Adrenal ablation significantly lowered systolic and diastolic blood pressure of the SHR (P < 0.05 or P < 0.01) but not WKY from 4 to 24 weeks after the procedure. Adrenal ablation substantially damaged adrenal cortex and medulla with fibrosis in SHR and WKY rats. The ablation procedure remarkably reduced the levels of renin, angiotensin II, aldosterone, cortisol, noradrenaline, and epinephrine in SHR (all P < 0.05) but not in WKY. Hypokalemia in SHR was significantly improved by adrenal ablation (P < 0.05), while the serum sodium levels were not affected by adrenal ablation in either SHR or WKY rats. Additionally, adrenal ablation improved cardiac, renal, and vascular remodeling and function measured 3 months after the procedure in SHR. In conclusion, the present study shows that ethanol ablation of adrenal gland can effectively lower blood pressure and prevent target organ damage in SHR. These findings suggest that unilateral debulking of the adrenal gland using ethanol ablation is a promising therapeutic strategy for treating hypertension.

METHODS

Spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) were subjected to unilateral adrenal ablation with injection of ethanol or a sham procedure. Blood pressure was monitored for 24 weeks.

RESULTS

Adrenal ablation significantly lowered systolic and diastolic blood pressure of SHR but not WKY from 4 to 24 weeks after the procedure.

CONCLUSION

Unilateral debulking of the adrenal gland using ethanol ablation is a promising therapeutic strategy for treating hypertension.

Endocrine causes of hypertension: literature review and practical approach

Hypertension (HTN) affects more than 30% of adults worldwide. It is the most frequent modifiable cardiovascular (CV) risk factor, and is responsible for more than 10 million death every year. Among patients with HTN, we usually distinguish secondary HTN, that is HTN due to an identified cause, and primary HTN, in which no underlying cause has been found. It is estimated that secondary hypertension represents between 5 and 15% of hypertensive patients [1]. Therefore, routine screening of patients for secondary HTN would be too costly and is not recommended. In addition to the presence of signs suggesting a specific secondary cause, screening is based on specific criteria. Identifying secondary HTN can be beneficial for patients in certain situations, because it may lead to specific treatments, and allow better control of blood pressure and sometimes even a cure. Besides, it is now known that secondary HTN are more associated with morbidity and mortality than primary HTN. The main causes of secondary HTN are endocrine and renovascular (mainly due to renal arteries abnormalities). The most frequent endocrine cause is primary aldosteronism, which diagnosis can lead to specific therapies. Pheochromocytoma and Cushing syndrome also are important causes, and can have serious complications. Other causes are less frequent and can be suspected on specific situations. In this article, we will describe the endocrine causes of HTN and discuss their treatments.

Predictors of long-term absence of coronary artery calcium in individuals with high blood pressure: results from the MESA study

BACKGROUND & AIMS

Individuals with high blood pressure (BP) have varying risks of cardiovascular events due to other coexisting factors. We aimed to identify the predictors of long-term absence of coronary artery calcium (CAC) in individuals with high BP, which is an indicator of healthy arterial aging and can guide preventive strategies.

METHODS

We analyzed data from participants with high BP (≥120/80 mm Hg) in the Multi-Ethnic Study of Atherosclerosis who had baseline CAC = 0 and underwent a second CAC scanning after 10 years. We used multivariable logistic regression to evaluate the association between various risk factors for atherosclerotic cardiovascular disease (ASCVD) and long-term CAC = 0. We also calculated the area under the receiver operating characteristic curve (AUC) to predict the phenotype of healthy arterial aging in this population.

RESULTS

We included 830 participants (37.6% male, mean ± SD age of 59.4 ± 8.7 years). During follow-up, 46.5% of participants (n = 386) had CAC = 0, and they were younger and had fewer metabolic syndrome components. Adding ASCVD risk factors to the demographic model (age, sex, and ethnicity) moderately increased the predictive value for long-term CAC = 0 (AUC: demographic model + ASCVD risk factors vs. demographic model alone, 0.653 vs. 0.597, p < .001; category net reclassification improvement = 0.104, p = .044; integrated discrimination improvement = 0.040, p < .001).

CONCLUSION

In individuals with high BP and initial CAC = 0, over 40% maintained CAC = 0 during a 10-year follow-up, which was associated with fewer ASCVD risk factors. These findings may have implications for preventive strategies in individuals with high BP.Clinical Trial registration number: The MESA was registered at clinical trials. gov as NCT00005487.KEY MESSAGESNearly half (46.5%) of individuals with high blood pressure (BP) maintained a long-term absence of coronary artery calcium (CAC) during a 10-year follow-up, and this was associated with a 66.6% lower risk of atherosclerotic cardiovascular disease (ASCVD) events compared to those who developed incident CAC.Individuals with high BP, who are usually assumed to have an increased risk of ASCVD, exhibit significant heterogeneity in their ASCVD risk; those who maintain CAC = 0 have a lower ASCVD risk.Adding overall ASCVD risk factors to demographic information resulted in a moderate improvement in predicting long-term CAC = 0.

Urinary cortisol and cardiovascular events in women vs. men: The multi-ethnic study of atherosclerosis

Research suggests that women experience greater cardiovascular ischemic effects from stress than men. Visceral adiposity is an endocrine tissue that differs by sex and interacts with stress hormones. We hypothesized that urinary cortisol would be associated with increased cardiovascular events and change in coronary artery calcium score (CAC) in women, and these relationships would vary by central obesity. In the Multi-Ethnic Study of Atherosclerosis Stress Ancillary study, cortisol was quantified by 12-h overnight urine collection. Central obesity was estimated by waist-hip ratio (WHR). Multivariable Cox models estimated the relationship between cortisol and cardiovascular events and assessed for moderation by WHR. The relationship between cortisol and change in CAC Agatston score was assessed by Tobit regression models. 918 patients were analyzed with median follow up of 11 years. There was no association between urinary cortisol and cardiovascular events in the cohort. However, in individuals with below median WHR, higher urinary cortisol levels (upper tertile) were associated with higher cardiovascular event rates in the full cohort, women, and men, but not in groups with above median WHR. There was significant moderation by WHR in women, but not men, whereby the association between elevated cortisol and increased cardiovascular events diminished as WHR increased. Urinary cortisol was associated with increased change in CAC in women (P = 0.003) but not men, without moderation by WHR. Our study highlights associations between cortisol and subclinical atherosclerosis in women, and moderation of the relationship between cortisol and cardiovascular events by central obesity in both genders.

Association of Reversal of Renin Suppression With Long-Term Renal Outcome in Medically Treated Primary Aldosteronism

BACKGROUND

Renin suppression in primary aldosteronism indicates mineralocorticoid receptor activation via excessive aldosterone secretion, inducing renal damage. We investigated whether the reversal of renin suppression after the initiation of mineralocorticoid receptor antagonist therapy was associated with long-term renal outcomes in medically treated patients with primary aldosteronism.

METHODS

This retrospective cohort study included 318 patients with primary aldosteronism treated with mineralocorticoid receptor antagonist between 2008 and 2020 at the Yokohama Rosai Hospital in Japan. The posttreatment renin status was defined as unsuppressed (ie, reversal of renin suppression) when individual plasma renin activity after the initiation of mineralocorticoid receptor antagonist (post-plasma renin activity) was ≥1.0 ng/mL per hour; otherwise, it was defined as suppressed. We analyzed the association of posttreatment renin status with subsequent longitudinal estimated glomerular filtration rate changes using linear mixed-effects models for repeated measurements, adjusting for potential confounders.

RESULTS

The posttreatment renin status of 119 patients was unsuppressed (median post-plasma renin activity, 1.7 ng/mL per hour) and that of 199 patients was suppressed (median post-PRA, 0.5 ng/mL per hour). Through the median follow-up period of 3.1 years, the decline in estimated glomerular filtration rate was milder among patients with the unsuppressed posttreatment renin (-0.46 [95% CI, -0.63 to -0.28] mL/min per 1.73 m2 per year) than those with suppressed posttreatment renin (-1.41 [95% CI, -1.56 to -1.27] mL/min per 1.73 m2 per year; difference, 0.96 [95% CI, 0.72-1.20] mL/min per 1.73 m2 per year).

CONCLUSIONS

Our findings may highlight the importance of reversing renin suppression with optimal mineralocorticoid receptor antagonist titration in medically treated primary aldosteronism, which could mitigate adverse renal outcomes.

Primary Aldosteronism and the Role of Mineralocorticoid Receptor Antagonists for the Heart and Kidneys

Primary aldosteronism (PA) is the most common cause of secondary hypertension but is frequently underrecognized and undertreated. Patients with PA are at a markedly increased risk for target organ damage to the heart and kidneys. While patients with unilateral PA can be treated surgically, many patients with PA are not eligible or willing to undergo surgery. Steroidal mineralocorticoid receptor antagonists (MRAs) are highly effective for treating PA and reducing the risk of target organ damage. However, steroidal MRAs are often underprescribed and can be poorly tolerated by some patients due to side effects. Nonsteroidal MRAs reduce adverse renal and cardiovascular outcomes among patients with diabetic kidney disease and are bettertolerated than steroidal MRAs. While their blood pressure-lowering effects remain unclear, these agents may have a potential role in reducing target organ damage in patients with PA.

Cardiovascular Disease in Obstructive Sleep Apnea: Putative Contributions of Mineralocorticoid Receptors

Obstructive sleep apnea (OSA) is a chronic and highly prevalent condition that is associated with oxidative stress, inflammation, and fibrosis, leading to endothelial dysfunction, arterial stiffness, and vascular insulin resistance, resulting in increased cardiovascular disease and overall mortality rates. To date, OSA remains vastly underdiagnosed and undertreated, with conventional treatments yielding relatively discouraging results for improving cardiovascular outcomes in OSA patients. As such, a better mechanistic understanding of OSA-associated cardiovascular disease (CVD) and the development of novel adjuvant therapeutic targets are critically needed. It is well-established that inappropriate mineralocorticoid receptor (MR) activation in cardiovascular tissues plays a causal role in a multitude of CVD states. Clinical studies and experimental models of OSA lead to increased secretion of the MR ligand aldosterone and excessive MR activation. Furthermore, MR activation has been associated with worsened OSA prognosis. Despite these documented relationships, there have been no studies exploring the causal involvement of MR signaling in OSA-associated CVD. Further, scarce clinical studies have exclusively assessed the beneficial role of MR antagonists for the treatment of systemic hypertension commonly associated with OSA. Here, we provide a comprehensive overview of overlapping mechanistic pathways recruited in the context of MR activation- and OSA-induced CVD and propose MR-targeted therapy as a potential avenue to abrogate the deleterious cardiovascular consequences of OSA.

Emerging vascular cell-specific roles for mineralocorticoid receptor: implications for understanding sex differences in cardiovascular disease

As growing evidence implicates extrarenal mineralocorticoid receptor (MR) in cardiovascular disease (CVD), recent studies have defined both cell- and sex-specific roles. MR is expressed in vascular smooth muscle (SMC) and endothelial cells (ECs). This review integrates published data from the past 5 years to identify novel roles for vascular MR in CVD, with a focus on understanding sex differences. Four areas are reviewed in which there is recently expanded understanding of the cell type- or sex-specific role of MR in 1) obesity-induced microvascular endothelial dysfunction, 2) vascular inflammation in atherosclerosis, 3) pulmonary hypertension, and 4) chronic kidney disease (CKD)-related CVD. The review focuses on preclinical data on each topic describing new mechanistic paradigms, cell type-specific mechanisms, sexual dimorphism if addressed, and clinical implications are then considered. New data support that MR drives vascular dysfunction induced by cardiovascular risk factors via sexually dimorphic mechanisms. In females, EC-MR contributes to obesity-induced endothelial dysfunction by regulating epithelial sodium channel expression and by inhibiting estrogen-induced nitric oxide production. In males with hyperlipidemia, EC-MR promotes large vessel inflammation by genomic regulation of leukocyte adhesion molecules, which is inhibited by the estrogen receptor. In pulmonary hypertension models, MRs in EC and SMC contribute to distinct components of disease pathologies including pulmonary vessel remodeling and RV dysfunction. Despite a female predominance in pulmonary hypertension, sex-specific roles for MR have not been explored. Vascular MR has also been directly implicated in CKD-related vascular dysfunction, independent of blood pressure. Despite these advances, sex differences in MR function remain understudied.

First survey on the diagnosis and treatment of primary aldosteronism by Spanish Endocrinology and Nutrition specialists

OBJECTIVE

To evaluate the indication and the resources for the screening/diagnosis of primary aldosteronism (PA) in Endocrinology units in Spain.

MATERIAL AND METHODS

An anonymous 2-phase (2020/2021) online survey was conducted by the AdrenoSEEN group among SEEN members with data about screening, confirmation tests, availability of catheterisation and the treatment of PA.

RESULTS

Eighty-eight (88) specialists completed the survey. Plasma aldosterone concentration and plasma renin activity were available at all centres; urinary aldosterone was available in 55% of them. The most frequent indications for determining the aldosterone/renin ratio (ARR) were adrenal incidentaloma (82.6%), hypertension with hypokalaemia (82.6%), hypertension in patients <40 years (79.1%) and a family history of PA (77.9%). 61% and 18% of the respondents used an ARR cut-off value of PA of ≥30 and 20ng/dl per ng/mL/, respectively. The intravenous saline loading test was the most commonly used confirmatory test (66.3%), followed by the captopril challenge test (24.4%), with the 25mg dose used more than the 50mg dose (65% versus 35%). 67.4% of the participants confirmed the availability of adrenal vein catheterization (AVC). 41% of this subgroup perform it with a continuous infusion versus 30.5% with an ACTH (1-24) bolus, whereas 70.3% employ sequential adrenal vein catheterization. 48% of the participants reported an AVC success <50%. Total laparoscopic adrenalectomy was the treatment of choice (90.6%), performed by specialists in General and Digestive Surgery specialising in endocrinological pathology.

CONCLUSION

PA screening and diagnostic tests are extensively available to Spanish endocrinologists. However, there is a major variability in their use and in the cut-off points of the diagnostic methods. The AVS procedure remains poorly standardised and is far from delivering optimal performance. Greater standardisation in the study and diagnosis of PA is called for.

Primary Aldosteronism: State-of-the-Art Review

We are witnessing a revolution in our understanding of primary aldosteronism (PA). In the past 2 decades, we have learned that PA is a highly prevalent syndrome that is largely attributable to pathogenic somatic mutations, that contributes to cardiovascular, metabolic, and kidney disease, and that when recognized, can be adequately treated with widely available mineralocorticoid receptor antagonists and/or surgical adrenalectomy. Unfortunately, PA is rarely diagnosed, or adequately treated, mainly because of a lack of awareness and education. Most clinicians still possess an outdated understanding of PA; from primary care physicians to hypertension specialists, there is an urgent need to redefine and reintroduce PA to clinicians with a modern and practical approach. In this state-of-the-art review, we provide readers with the most updated knowledge on the pathogenesis, prevalence, diagnosis, and treatment of PA. In particular, we underscore the public health importance of promptly recognizing and treating PA and provide pragmatic solutions to modify clinical practices to achieve this.

The renin-angiotensin-aldosterone system, neurohumoral axis and cardiovascular mortality in LURIC

Although neurohormones and Renin-Angiotensin-Aldosterone-System (RAAS) components are important predictors of cardiovascular mortality (CVM), their importance for predicting outcomes in patients with/without RAAS-blockers and different degrees of arterial stiffness is less understood. We therefore analyzed long-term data from the Ludwigshafen Risk and Cardiovascular Health (LURIC) study in 3316 patients subdivided according to pulse pressure (PP) and RAAS-blocker use. Patients on RAAS-inhibition had higher renin and noradrenaline, lower aldosterone and aldosterone/renin quotient (ARQ). Renin and noradrenaline significantly predicted CVM in patients without RAAS-blocker (HR = 1.17, 1.15) and in patients receiving angiotensin-converting-enzyme (ACE) inhibitors (HR = 1.17, 1.29), whereas aldosterone predicted CVM only in patients receiving ACE-inhibitors (HR = 1.13). CVM was predicted independently from PP by renin, noradrenaline and angiotensin II. Independently from RAAS inhibition renin decreased and ARQs increased with rising PP. Furthermore, noradrenaline increased with PP, but only without ACE-inhibition. The HR for CVM in the ACE-inhibitor group were 1.29, 1.28, 1.29 for renin in the first, second and third PP quartiles and 1.22, and 1.19 for aldosterone in the second and fourth quartile. Furthermore, we showed that noradrenaline predicts CVM in all PP quartiles in patients with ACE-inhibition. In the RAAS-blocker-free group, the HR for renin for CVM were 1.36 and 1.18 in the third and fourth PP quartiles, but neither aldosterone nor noradrenaline were predictive for CVM within the PP quartiles. Renin and noradrenaline are strong predictors of CVM regardless of RAAS blockade, whereas aldosterone is predictive only in the ACE-inhibitor group. Catecholamines but not renin are associated with rising PP.

Primary aldosteronism - a multidimensional syndrome

Primary aldosteronism is a common cause of hypertension and is a risk factor for cardiovascular and renal morbidity and mortality, via mechanisms mediated by both hypertension and direct insults to target organs. Despite its high prevalence and associated complications, primary aldosteronism remains largely under-recognized, with less than 2% of people in at-risk populations ever tested. Fundamental progress made over the past decade has transformed our understanding of the pathogenesis of primary aldosteronism and of its clinical phenotypes. The dichotomous paradigm of primary aldosteronism diagnosis and subtyping is being redefined into a multidimensional spectrum of disease, which spans subclinical stages to florid primary aldosteronism, and from single-focal or multifocal to diffuse aldosterone-producing areas, which can affect one or both adrenal glands. This Review discusses how redefining the primary aldosteronism syndrome as a multidimensional spectrum will affect the approach to the diagnosis and subtyping of primary aldosteronism.

Aldosterone in chronic kidney disease and renal outcomes

AIMS

Randomized controlled trials have demonstrated the efficacy of mineralocorticoid receptor (MR) antagonism in delaying chronic kidney disease (CKD) progression in diabetes; however, they have not investigated the role of aldosterone or whether these beneficial effects could be achieved in individuals without diabetes.

METHODS AND RESULTS

The association between serum aldosterone concentrations and kidney disease progression was investigated among 3680 participants in the Chronic Renal Insufficiency Cohort. The primary outcome was CKD progression [defined as the composite of 50% decline in estimated glomerular filtration rate (eGFR) or end-stage kidney disease, whichever occurred first]. The associations between serum aldosterone and kidney disease outcomes were assessed using Cox proportional hazard models. At baseline, higher aldosterone concentrations were associated with a lower eGFR, lower serum potassium, greater urinary potassium, and protein excretion. Over a median follow-up of 9.6 years, 1412 participants developed CKD progression. In adjusted models, each doubling of serum aldosterone was associated with a 11% increased risk of CKD progression [hazard ratio (HR) 1.11, 95% confidence interval (CI) 1.04-1.18]. Individuals with the highest quartile of serum aldosterone had a 45% increased risk of CKD progression (HR 1.45, 95% CI 1.22-1.73) compared with the lowest quartile. The risk for CKD progression was similar regardless of whether patients had concomitant diabetes (P-interaction = 0.10).

CONCLUSION

Higher serum aldosterone levels among individuals with CKD are independently associated with an increased risk for kidney disease progression, irrespective of concomitant diabetes. These findings provide mechanistic support for MR antagonists in delaying CKD progression and suggest that they may also have a role in those without diabetes.

Cardiac Structure and Function Across the Spectrum of Aldosteronism: the Atherosclerosis Risk in Communities Study

BACKGROUND

Aldosterone production and mineralocorticoid receptor activation are implicated in myocardial fibrosis and cardiovascular events.

METHODS

Cardiac structure and function were assessed in 4547 participants without prevalent heart failure (HF) in the ARIC study (Atherosclerosis Risk in Communities), with echocardiography, aldosterone, and plasma renin activity measurement (2011-2013). Subjects were characterized by plasma renin activity as suppressed (≤0.5 ng/mL per hour) or unsuppressed (>0.5 ng/mL per hour). Cross-sectional relationships with cardiac structure and function, and longitudinal relationships with outcomes (HF hospitalization; HF and all-cause death; HF, death, myocardial infarction, and stroke; and incident atrial fibrillation) were assessed. Models were adjusted for demographic and anthropometric characteristics and additively, for blood pressure and antihypertensives.

RESULTS

Evidence of primary aldosteronism physiology was prevalent (11.6% with positive screen) and associated with echocardiographic parameters. Renin suppression was associated with greater left ventricular mass, left ventricular volumes, and left atrial volume index, and a lower E/A ratio (adjusted P<0.001 for all). Higher aldosterone was associated with greater left ventricular mass and lower global longitudinal strain and lateral E'. The highest tertile of aldosterone was associated with a hazard ratio of 1.37 (95% CI, 1.06-1.77; 5.5-year follow-up) for incident atrial fibrillation relative to the lowest. Renin suppression was associated with HF (hazard ratio, 1.34 [95% CI, 1.05-1.72]; 7.3-year follow-up), although these relationships did not remain statistically significant after additional adjustment for hypertension.

CONCLUSIONS

Renin suppression and aldosterone excess, consistent with primary aldosteronism pathophysiology, were associated with cardiac structural and functional alterations and may represent an early target for mitigation of fibrosis with mineralocorticoid receptor antagonists.

Aldosterone as a Mediator of Cardiovascular Damage

Besides the physiological regulation of water, sodium, and potassium homeostasis, aldosterone modulates several physiological and pathological processes in the cardiovascular system. At the vascular level, aldosterone excess stimulates endothelial dysfunction and infiltration of inflammatory cells, enhances the development of the atherosclerotic plaque, and favors plaque instability, arterial stiffness, and calcification. At the cardiac level, aldosterone increases cardiac inflammation, fibrosis, and myocardial hypertrophy. As a clinical consequence, high aldosterone levels are associated with enhanced risk of cardiovascular events and mortality, especially when aldosterone secretion is inappropriate for renin levels and sodium intake, as in primary aldosteronism. Several clinical trials showed that mineralocorticoid receptor antagonists reduce cardiovascular mortality in patients with heart failure and reduced ejection fraction, but inconclusive results were reported for other cardiovascular conditions, such as heart failure with preserved ejection fraction, myocardial infarction, and atrial fibrillation. In patients with primary aldosteronism, adrenalectomy or treatment with mineralocorticoid receptor antagonists significantly mitigate adverse aldosterone effects, reducing the risk of cardiovascular events, mortality, and incident atrial fibrillation. In this review, we will summarize the major preclinical and clinical studies investigating the cardiovascular damage mediated by aldosterone and the protective effect of mineralocorticoid receptor antagonists for the reduction of cardiovascular risk in patients with cardiovascular diseases and primary aldosteronism.

Oxidative Stress in Arterial Hypertension (HTN): The Nuclear Factor Erythroid Factor 2-Related Factor 2 (Nrf2) Pathway, Implications and Future Perspectives

Arterial hypertension (HTN) is one of the most prevalent entities globally, characterized by increased incidence and heterogeneous pathophysiology. Among possible etiologies, oxidative stress (OS) is currently extensively studied, with emerging evidence showing its involvement in endothelial dysfunction and in different cardiovascular diseases (CVD) such as HTN, as well as its potential as a therapeutic target. While there is a clear physiological equilibrium between reactive oxygen species (ROS) and antioxidants essential for many cellular functions, excessive levels of ROS lead to vascular cell impairment with decreased nitric oxide (NO) availability and vasoconstriction, which promotes HTN. On the other hand, transcription factors such as nuclear factor erythroid factor 2-related factor 2 (Nrf2) mediate antioxidant response pathways and maintain cellular reduction-oxidation homeostasis, exerting protective effects. In this review, we describe the relationship between OS and hypertension-induced endothelial dysfunction and the involvement and therapeutic potential of Nrf2 in HTN.

Serum Calcification Propensity and Calcification of the Abdominal Aorta in Patients With Primary Aldosteronism

Patients with primary aldosteronism (PA) are more susceptible to cardiovascular disease and mortality than patients with primary hypertension. This is mostly attributed to excess production of aldosterone and its effects on the development of vascular injury. A novel functional test (T₅₀) measures serum calcification propensity. Lower T₅₀-values predict higher cardiovascular risk. We investigated serum calcification propensity and vascular calcification in PA and resistant hypertension (RH). T₅₀ measurement was performed in patients with PA (n = 66) and RH (n = 28) at baseline and after 403 (279–640) and 389 (277–527) days of treatment. No significant differences in T₅₀-values were observed between the groups (371 ± 65 and 382 ± 44 min, in PA and RH group, respectively, p > 0.05). However, higher aldosterone-to-renin ratios were associated with lower T₅₀-values in PA-patients (r −0.282, p < 0.05). Furthermore, lower T₅₀-values were associated with increased abdominal aortic calcification measured by Agatston score in PA (r −0.534, p < 0.05). In both, PA and RH, higher atherosclerotic cardiovascular disease (ACSVD) scores (r −0.403, p < 0.05) and lower HDL (r 0.469, p < 0.05) was related to lower T₅₀-values in a linear regression model. Adrenalectomy or medical treatment did not increase T₅₀-values. In comparison to patients with stable T₅₀-values, PA patients with a decrease in T₅₀ after intervention had higher serum calcium concentrations at baseline (2.24 ± 0.11 vs. 2.37 ± 0.10 mmol/l, p < 0.05). This decline of T₅₀-values at follow-up was also associated with a decrease in serum magnesium (−0.03 ± 0.03 mmol/l, p < 0.05) and an increase in phosphate concentrations (0.11 ± 0.11 mmol/l, p < 0.05). Resistant hypertension patients with a decrease in T₅₀-values at follow-up had a significantly lower eGFR at baseline. In summary, these data demonstrate an association between a high aldosterone-to-renin ratio and low T₅₀-values in PA. Moreover, lower T₅₀-values are associated with higher ACSVD scores and more pronounced vascular calcification in PA. Thus, serum calcification propensity may be a novel modifiable risk factor in PA.

Higher Plasma Aldosterone Concentrations Are Associated With Elevated Risk of Aortic Dissection and Aneurysm: a Case-Control Study

BACKGROUND

Animal models demonstrate circulating aldosterone leads to aortic dissection and aneurysm, whereas data from humans are lacking. Therefore, we aimed to examine the associations of plasma aldosterone concentrations (PAC) with aortic dissection and aneurysm.

METHODS

We identified patients with aortic dissection and aneurysm with assessed PAC before disease onset from hospital-based electronic database and set as case group. Simultaneously, age and gender-matched cohort with PAC measurement whereas without aortic dissection and aneurysm were selected as control group using ratio of 1:4. Multi-variable logistic regression analysis was used to assess the relationship of PAC with aortic dissection and aneurysm.

RESULTS

Totally, 133 cases and 531 controls (all hypertensive) were enrolled between 2004 and 2021, with 77.9% men, mean age of 55.5 years and PAC of 13.9 ng/dL. Case group showed significantly higher PAC(14.51 versus 13.65 ng/dL, P=0.012) than did control group. In logistic regression analysis, higher PAC exhibited 1.68-fold higher odds (95% CI, 1.14-2.48, P=0.008) for presence of aortic dissection and aneurysm, significant in adjusted model (odds ratio, 1.69 [95% CI, 1.11-2.57], P=0.015). In stratified analysis, the association between the 2 was observed in women of all ages and in men with coronary artery disease. Sensitivity analysis by excluding those under interfering agents at PAC measurement and those with primary aldosteronism did not change the relationship of the 2.

CONCLUSIONS

Higher PAC is associated with the increased odd for aortic dissection and aneurysm in patients with hypertension, even in the absence of primary aldosteronism, implying that PAC might be a target for prevention.

Association of objective and subjective parameters of obstructive sleep apnea with plasma aldosterone concentration in 2,066 hypertensive and 25,368 general population

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) severity has been suggested in aldosterone elevation in resistant hypertension, whereas it is undetermined in the rest population. We explored the association of OSA parameters with plasma aldosterone concentration (PAC) in participants with and without hypertension.

METHODS

We enrolled clinically hypertensive patients with polysomnography and PAC data under no interfering agents, compared (log) PAC, and assessed the linearity of log PAC by tertiles (T1/2/3) of sleep parameters and their association using linear regression by gender and age. We enrolled participants with and without hypertension who had No-SAS scale and PAC data from the community and duplicated the observations from clinical setting considering age, gender, and presence of hypertension.

RESULTS

Of the 2,066 clinical patients with hypertension (1,546 with OSA), men participants (n=1,412), log apnea-hypopnea index (p=0.043), apnea index (AI, p=0.010), and lowest oxygen saturation (LSaO₂, p=0.013) showed significant linearity with log PAC. Log AI (B=0.04, 95%CI: 0.01,0.07, p=0.022) and log LSaO₂ (B=-0.39, 95%CI: -0.78,-0.01, p=0.044) showed significant positive and negative linear associations with log PAC in regression. In community dwellers, 6,417 participants with untreated hypertension (2,642 with OSA) and 18,951 normotensive participants (3,000 with OSA) were included. Of the men participants with and without hypertension, the OSA group showed significantly higher (log) PAC than did their counterparts, and log No-SAS score showed positive association with log PAC (hypertension: B=0.072, 95%CI: 0.002,0.142, p=0.043; normotension: B=0.103, 95%CI: 0.067,0.139, p<0.001) in linear regression analysis, which were consistent in all age groups.

CONCLUSIONS

OSA parameters were positively associated with PAC in normotensive and hypertensive participants, indicating that OSA may increase circulating aldosterone, especially in men.

Higher plasma aldosterone is associated with increased risk of cardiovascular events in hypertensive patients with suspected OSA: UROSAH data

OBJECTIVE

To evaluate the association of plasma aldosterone concentration (PAC) with incident cardiovascular disease (CVD) and all-cause mortality in hypertensive patients with suspected obstructive sleep apnea (OSA) and calculate the optimal cut-off value of PAC for this specific population.

PATIENTS AND METHODS

Participants with PAC at baseline in UROSAH in 2011-2013 were enrolled and followed up till 2021. Composite outcome included CVD and all-cause mortality. Cox proportional hazards model was used to evaluate the relationship between PAC and the composite outcome. Time-dependent ROC curve was used to determine the optimal cut-off value of PAC. Besides, we conducted subgroup analyses and sensitivity analyses.

RESULTS

3173 hypertensive participants aged 18-84 years comprised analytical sample. During a median follow-up of 7.3 years and 22640 person-years, 69 deaths and 343 cases of incident CVD occurred. The incidence of composite outcome was increased with elevation in tertile of PAC. Compared with the first tertile, the risk of CVD and all-cause death was higher in third tertile (HR=1.81, 95%CI: 1.39-2.35, P<0.001). Time-dependent ROC curve showed optimal threshold for PAC was 12.5ng/dl. Whether renin was suppressed or not (≤0.5 or >0.5ng/ml per h), elevated PAC was associated with an increased risk of CVD. Our results remained stable and consistent in sensitivity analyses.

CONCLUSION

Higher PAC was associated with increased risk of CVD and all-cause mortality in hypertensives with suspected OSA, even in the absence of primary aldosteronism (PA). Hypertensives with PAC≥12.5ng/dl showed a significantly increased risk of CVD, indicating that special attention and treatment were required in this specific population.

Heightened Cardiovascular Risk in Hypertension Associated With Renin-Independent Aldosteronism Versus Renin-Dependent Aldosteronism: A Collaborative Study

Background While both renin-dependent and renin-independent aldosterone secretion contribute to aldosteronism, their relative associations with cardiovascular disease (CVD) risk has not been investigated. Methods and Results A total of 2909 participants from the FOS (Framingham Offspring Study) with baseline, serum aldosterone concentration, and plasma renin concentration who attended the sixth examination cycle and were followed up until 2014 and who were free of CVD were included. We further recruited 2612 hypertensive participants from the CONPASS (Chongqing Primary Aldosteronism Study). Captopril challenge test was performed to confirm renin-dependent or -independent aldosteronism in CONPASS. Among 1433 hypertensive subjects of FOS, when compared with those with serum aldosterone concentration <10 ng dL^-1 (normal aldosterone), participants who had serum aldosterone concentration ≥10 ng dL^-1 and plasma renin concentration ≤15 mIU L^-1 (identified as renin-independent aldosteronism) showed a higher risk of CVD (hazard ratio, 1.40 [95% CI, 1.08-1.82]), while those who had serum aldosterone concentration ≥10 ng dL^-1 and plasma renin concentration >15 mIU L^-1 (identified as renin-dependent aldosteronism) showed an unchanged CVD risk. In CONPASS, renin-independent aldosteronism carried a significantly higher risk of CVD than normal aldosterone (odds ratio, 2.57 [95% CI, 1.13-5.86]), while the CVD risk remained unchanged in renin-dependent aldosteronism. Elevation of the urinary potassium-to-sodium excretion ratio, reflective of mineralocorticoid receptor activity, was only observed in participants with renin-independent aldosteronism. Conclusions Among patients with hypertension, renin-independent aldosteronism is more closely associated with CVD risk than renin-dependent aldosteronism.

Diagnosis and treatment of primary aldosteronism

Primary aldosteronism is a common cause of secondary hypertension associated with excess cardiovascular morbidities. Primary aldosteronism is underdiagnosed because it does not have a specific, easily identifiable feature and clinicians can be poorly aware of the disease. The diagnostic investigation is a multistep process of screening, confirmatory testing, and subtype differentiation of unilateral from bilateral forms for therapeutic management. Adrenal venous sampling is key for reliable subtype identification, but can be bypassed in patients with specific characteristics. For unilateral disease, surgery offers the possibility of cure, with total laparoscopic unilateral adrenalectomy being the treatment of choice. Bilateral forms are treated mainly with mineralocorticoid receptor antagonists. The goals of treatment are to normalise both blood pressure and excessive aldosterone production, and the primary aims are to reduce associated comorbidities, improve quality of life, and reduce mortality. Prompt diagnosis of primary aldosteronism and the use of targeted treatment strategies mitigate aldosterone-specific target organ damage and with appropriate patient management outcomes can be excellent. Advances in molecular histopathology challenge the traditional concept of primary aldosteronism as a binary disease, caused by either a unilateral aldosterone-producing adenoma or bilateral adrenal hyperplasia. Somatic mutations drive autonomous aldosterone production in most adenomas. Many of these same mutations have been identified in nodular lesions adjacent to an aldosterone-producing adenoma and in patients with bilateral disease. In addition, germline mutations cause rare familial forms of aldosteronism (familial hyperaldosteronism types 1-4). Genetic testing for inherited forms in suspected cases of familial hyperaldosteronism avoids the burdensome diagnostic investigation in positive patients. In this Review, we discuss advances and future management approaches in the diagnosis of primary aldosteronism.

Autonomous Aldosterone Secretion as a Subclinical Form of Primary Aldosteronism: Pathogenesis and Clinical Significance

In recent years, a substantial prevalence of primary aldosteronism (PA) has been demonstrated in both normotensive and mildly hypertensive cohorts. Consequently, a classic presentation of the syndrome, i. e. moderate-to-severe and resistant hypertension with concomitant hypokalemia, should be considered a tip-of-the-iceberg phenotype of a wide PA spectrum. Its entire range encompasses the non-classic clinical forms of mild hypertension and prehypertension but also several biochemical presentations, including patients who meet PA screening and confirmation test criteria, as well as those with either of them and those with other parameters indicating mineralocorticoid excess. In the current review, research insights on the pathogenetic background and clinical significance of autonomous aldosterone secretion (AAS) are presented, which is defined as a constellation of either: 1) normotension, normokalemia, a positive PA screening (high aldosterone-to-renin ratio) and/or confirmation test, or 2) hypertension, normokalemia and a positive PA screening but negative confirmation test. For this purpose, a literature search of the PubMed database was conducted. Advances in immunohistochemistry and genetic sequencing of isolated adrenal cells are provided as probable morphologic basis of the wide range of aldosterone secretion autonomy. Also, the role of corticotropin as an aldosterone secretagogue is discussed. To date, clinical studies depict consequences of subclinical PA phenotypes, such as increased mortality and risk of developing hypertension, impaired arterial and kidney function, association with metabolic syndrome and age, as well as osteoporosis.

Urinary Stress Hormones, Hypertension, and Cardiovascular Events: The Multi-Ethnic Study of Atherosclerosis

[Figure: see text].

Cortisol Co-Secretion and Clinical Usefulness of ACTH Stimulation Test in Primary Aldosteronism: A Systematic Review and Biases in Epidemiological Studies

The hypothalamus-pituitary-adrenal (HPA) axis plays an important role in primary aldosteronism. Aldosterone biosynthesis is regulated not only by angiotensin II in the renin-angiotensin-aldosterone system, but also by adrenocorticotropic hormone (ACTH), one of the key components of the HPA axis. Although previous studies have reported cortisol cosecretion in primary aldosteronism, particularly aldosterone-producing adenoma (APA), the clinical relevance of such aldosterone and cortisol cosecretion from APA and hypertension or other metabolic disorders has not been fully established. Several somatic mutations including KCNJ5 and CACNA1D are known to induce autonomous production of aldosterone in APA, and the aldosterone responsiveness to ACTH may vary according to each mutation. The ACTH stimulation test has been reported to be a useful tool to distinguish the subtypes of primary aldosteronism (e.g., unilateral vs bilateral) in some studies, but it has not been commonly applied in clinical practice due to limited evidence. Given the recent advancement of imaging, omics research, and computational approach, it is important to summarize the most updated evidence to disentangle the potential impact of cortisol excess in primary aldosteronism and whether the ACTH stimulation test needs to be considered during the diagnostic process of primary aldosteronism. In this article, we conducted a systematic review of epidemiological studies about (i) cortisol cosecretion in primary aldosteronism and (ii) the ACTH stimulation test for the diagnosis of primary aldosteronism (including subtype diagnosis). Then, we discussed potential biases (e.g., confounding bias, overadjustment, information bias, selection bias, and sampling bias) in the previous studies and introduced some advanced epidemiological/statistical methods to minimize these limitations. A better understanding of biases and epidemiological perspective on this topic would allow us to produce further robust evidence and balanced discussion about the causal mechanisms involving the HPA axis and clinical usefulness of the ACTH stimulation test among patients with primary aldosteronism.

Positive Association Between Plasma Aldosterone Concentration and White Matter Lesions in Patients With Hypertension

BACKGROUND AND OBJECTIVE

White matter lesions (WMLs) are imaging changes in MRI of cerebral small vessel disease associated with vascular risk factors, increasing the risk of dementia, depression, and stroke. Aldosterone (ALD) or activation of mineralocorticoid receptor (MR) causes cerebrovascular injury in a mouse model. We aimed to analyze the relationship between ALD and WMLs in a population with hypertension.

METHODS

We conducted a retrospective review of all patients screened for causes of secondary hypertension. We enrolled 547 patients with WMLs and matched these to controls without WMLs at a 1:1 ratio. White matter lesion load was assessed by using a modified Scheltens' scale.

RESULTS

Among the analytic sample (N = 1,094) with ages ranging from 30 to 64 years, 62.2% were male. We divided plasma ALD concentration (PAC), plasma renin activity (PRA), and ALD-renin ratio (ARR) into the third tertile (Q3), second tertile (Q2), and first tertile (Q1). We also analyzed them simultaneously as continuous variables. Multivariate logistic regression analysis showed that participants in Q3 (>17.26 ng/dl) of PAC (OR 1.59, 95% CI 1.15, 2.19), Q3 (<0.80 ng/dl) of PRA (OR 2.50, 95% CI 1.81, 3.44), and Q3 (>18.59 ng/dl per ng/ml*h) of ARR (OR 2.90, 95% CI 2.10, 4.01) had a significantly higher risk of WMLs than those in Q1 (<12.48) of PAC, Q1 (>2.19) of PRA, and Q1 (<6.96) of ARR. In linear regression analysis, we separately analyzed the correlation between the modified Scheltens' scale score and log(PAC) (β = 2.36; 95% CI 1.30, 3.41; p < 0.001), log(PRA) (β = -1.76; 95% CI -2.09, -1.43; p < 0.001), and log(ARR) (β = 1.86; 95% CI 1.55, 2.17; p < 0.001), which were all significantly correlated with white matter lesion load, after adjusting for confounding factors. Simple mediation analyses showed that systolic blood pressure (SBP) or diastolic blood pressure (DBP) mediated -3.83% or -2.66% of the association between PAC and white matter lesion load, respectively. In stratified analyses, there was no evidence of subgroup heterogeneity concerning the change in the risk of WMLs (p > 0.05 for interaction for all).

CONCLUSION

Higher PAC, especially in PAC >17.26 ng/dl, increased the risk of WMLs. PAC was positively associated with white matter lesion load independent of SBP or DBP.

Evolution of the Primary Aldosteronism Syndrome: Updating the Approach

CONTEXT

New approaches are needed to address the evolution of the primary aldosteronism syndrome and to increase its recognition. Herein, we review evidence indicating that primary aldosteronism is a prevalent syndrome that is mostly unrecognized, and present a pragmatic and pathophysiology-based approach to improve diagnosis and treatment.

METHODS

Evidence was gathered from published guidelines and studies identified from PubMed by searching for primary aldosteronism, aldosterone, renin, and hypertension. This evidence was supplemented by the authors' personal knowledge, research experience, and clinical encounters in primary aldosteronism.

INTERPRETATION OF EVIDENCE

Renin-independent aldosterone production is a prevalent phenotype that is diagnosed as primary aldosteronism when severe in magnitude, but is largely unrecognized when milder in severity. Renin-independent aldosterone production can be detected in normotensive and hypertensive individuals, and the magnitude of this biochemical phenotype parallels the magnitude of blood pressure elevation, the risk for incident hypertension and cardiovascular disease, and the likelihood and magnitude of blood pressure reduction with mineralocorticoid receptor antagonist therapy. Expansion of the indications to screen for primary aldosteronism, combined with the use of a pathophysiology-based approach that emphasizes inappropriate aldosterone production in the context of renin suppression, will substantially increase the diagnostic and therapeutic yields for primary aldosteronism.

CONCLUSIONS

The landscape of primary aldosteronism has evolved to recognize that it is a prevalent syndrome of renin-independent aldosterone production that contributes to the pathogenesis of hypertension and cardiovascular disease. Expanding screening indications and simplifying the diagnostic approach will enable implementation of targeted treatment for primary aldosteronism.