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.

A review of mitotane in the management of adrenocortical cancer.

IMPORTANCE: Mitotane (Lysodren, o,p'-DDD [1-(o-chlorophenyl)-1-(p-chlorophenyl)-2,2-dichloroethane)] is currently the only United States Food and Drug Administration and European Medicines Agency-approved product for the treatment of adrenocortical carcinoma. OBSERVATIONS: Mitotane is challenging to administer; however, its toxicities (specifically adrenal insufficiency) are well known, and the management of adverse consequences has established approaches. While often viewed through the prism of a cytotoxic agent, it can also interfere with hormone production making it a valuable asset in managing functional ACC. A recently completed prospective trial has shed some light on its use in the adjuvant setting, but further clarity is needed. Many think mitotane has a role in the advanced or metastatic setting, although prospective data are lacking and retrospective analyses are often difficult to interpret. CONCLUSIONS AND RELEVANCE: When used carefully and thoughtfully, especially in patients with hormonal excess, mitotane is an important component of the treatment armamentarium for ACC.

Structural analyses of an RNA stability element interacting with poly(A).

Cis-acting RNA elements are crucial for the regulation of polyadenylated RNA stability. The element for nuclear expression (ENE) contains a U-rich internal loop flanked by short helices. An ENE stabilizes RNA by sequestering the poly(A) tail via formation of a triplex structure that inhibits a rapid deadenylation-dependent decay pathway. Structure-based bioinformatic studies identified numerous ENE-like elements in evolutionarily diverse genomes, including a subclass containing two ENE motifs separated by a short double-helical region (double ENEs [dENEs]). Here, the structure of a dENE derived from a rice transposable element (TWIFB1) before and after poly(A) binding (∼24 kDa and ∼33 kDa, respectively) is investigated. We combine biochemical structure probing, small angle X-ray scattering (SAXS), and cryo-electron microscopy (cryo-EM) to investigate the dENE structure and its local and global structural changes upon poly(A) binding. Our data reveal 1) the directionality of poly(A) binding to the dENE, and 2) that the dENE-poly(A) interaction involves a motif that protects the 3'-most seven adenylates of the poly(A). Furthermore, we demonstrate that the dENE does not undergo a dramatic global conformational change upon poly(A) binding. These findings are consistent with the recently solved crystal structure of a dENE+poly(A) complex [S.-F. Torabi et al., Science 371, eabe6523 (2021)]. Identification of additional modes of poly(A)-RNA interaction opens new venues for better understanding of poly(A) tail biology.

Evaluating the clinical and mechanistic effects of eplerenone and amiloride monotherapy, and combination therapy with cinacalcet, in primary hyperparathyroidism: A placebo-controlled randomized trial.

OBJECTIVES: Human physiology and epidemiology studies have demonstrated complex interactions between the renin-angiotensin-aldosterone system, parathyroid hormone and calcium homeostasis. Several of these studies have suggested that aldosterone inhibition may lower parathyroid hormone (PTH) levels. The objective of this study was to assess the effect of 4 weeks of maximally tolerated mineralocorticoid receptor antagonist therapy with eplerenone on PTH levels in patients with primary hyperparathyroidism (P-HPT) when compared to amiloride and placebo. We also investigated the synergistic effect of these interventions when combined with cinacalcet for an additional 2 weeks. DESIGN: Randomized, double-blinded, three parallel-group, placebo-controlled trial. PATIENTS: Patients with P-HPT. RESULTS: Most patients were women (83%) and White (76%). Maximally tolerated doses of eplerenone and amiloride induced significant reductions in blood pressure and increases in renin and aldosterone production; however, despite these physiologic changes, neither intervention induced significant changes in PTH or calcium levels when compared to the placebo. Both eplerenone and amiloride therapy induced significant reductions in procollagen type 1 N-terminal propeptide levels when compared to placebo. When cinacalcet therapy was added, PTH and calcium levels were markedly reduced in all groups; however, there was no significant difference in PTH or serum calcium reductions between groups. CONCLUSIONS: Although maximally tolerated therapy with eplerenone and amiloride induced expected changes in renin, aldosterone and blood pressure, there were no meaningful changes in PTH or serum calcium levels in P-HPT patients. These results suggest that inhibition of aldosterone action does not have a clinically meaningful role in medical therapy for P-HPT.

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.

Aldosterone Synthase Inhibition With Lorundrostat for Uncontrolled Hypertension: The Target-HTN Randomized Clinical Trial.

Importance: Excess aldosterone production contributes to hypertension in both classical hyperaldosteronism and obesity-associated hypertension. Therapies that reduce aldosterone synthesis may lower blood pressure. Objective: To compare the safety and efficacy of lorundrostat, an aldosterone synthase inhibitor, with placebo, and characterize dose-dependent safety and efficacy to inform dose selection in future trials. Design, Setting, and Participants: Randomized, placebo-controlled, dose-ranging trial among adults with uncontrolled hypertension taking 2 or more antihypertensive medications. An initial cohort of 163 participants with suppressed plasma renin (plasma renin activity [PRA] ≤1.0 ng/mL/h) and elevated plasma aldosterone (≥1.0 ng/dL) were enrolled, with subsequent enrollment of 37 participants with PRA greater than 1.0 ng/mL/h. Interventions: Participants were randomized to placebo or 1 of 5 dosages of lorundrostat in the initial cohort (12.5 mg, 50 mg, or 100 mg once daily or 12.5 mg or 25 mg twice daily). In the second cohort, participants were randomized in a 1:6 ratio to placebo or lorundrostat, 100 mg once daily. Main Outcomes and Measures: The primary end point was change in automated office systolic blood pressure from baseline to study week 8. Results: Between July 2021 and June 2022, 200 participants were randomized, with final follow-up in September 2022. Following 8 weeks of treatment in participants with suppressed PRA, changes in office systolic blood pressure of -14.1, -13.2, -6.9, and -4.1 mm Hg were observed with 100 mg, 50 mg, and 12.5 mg once daily of lorundrostat and placebo, respectively. Observed reductions in systolic blood pressure in individuals receiving twice-daily doses of 25 mg and 12.5 mg of lorundrostat were -10.1 and -13.8 mm Hg, respectively. The least-squares mean difference between placebo and treatment in systolic blood pressure was -9.6 mm Hg (90% CI, -15.8 to -3.4 mm Hg; P = .01) for the 50-mg once-daily dose and -7.8 mm Hg (90% CI, -14.1 to -1.5 mm Hg; P = .04) for 100 mg daily. Among participants without suppressed PRA, 100 mg once daily of lorundrostat decreased systolic blood pressure by 11.4 mm Hg (SD, 2.5 mm Hg), which was similar to blood pressure reduction among participants with suppressed PRA receiving the same dose. Six participants had increases in serum potassium above 6.0 mmol/L that corrected with dose reduction or drug discontinuation. No instances of cortisol insufficiency occurred. Conclusions and Relevance: Among individuals with uncontrolled hypertension, use of lorundrostat was effective at lowering blood pressure compared with placebo, which will require further confirmatory studies. Trial Registration: ClinicalTrials.gov Identifier: NCT05001945.

The Unrecognized Prevalence of Primary Aldosteronism: A Cross-sectional Study.

BACKGROUND: Primary aldosteronism is a nonsuppressible renin-independent aldosterone production that causes hypertension and cardiovascular disease. OBJECTIVE: To characterize the prevalence of nonsuppressible renin-independent aldosterone production, as well as biochemically overt primary aldosteronism, in relation to blood pressure. DESIGN: Cross-sectional study. SETTING: 4 U.S. academic medical centers. PARTICIPANTS: Participants with normotension (n = 289), stage 1 hypertension (n = 115), stage 2 hypertension (n = 203), and resistant hypertension (n = 408). MEASUREMENTS: Participants completed an oral sodium suppression test, regardless of aldosterone or renin levels, as a confirmatory diagnostic for primary aldosteronism and to quantify the magnitude of renin-independent aldosterone production. Urinary aldosterone was measured in participants in high sodium balance with suppressed renin activity. Biochemically overt primary aldosteronism was diagnosed when urinary aldosterone levels were higher than 12 µg/24 h. RESULTS: Every blood pressure category had a continuum of renin-independent aldosterone production, where greater severity of production was associated with higher blood pressure, kaliuresis, and lower serum potassium levels. Mean adjusted levels of urinary aldosterone were 6.5 µg/24 h (95% CI, 5.2 to 7.7 µg/24 h) in normotension, 7.3 µg/24 h (CI, 5.6 to 8.9 µg/24 h) in stage 1 hypertension, 9.5 µg/24 h (CI, 8.2 to 10.8 µg/24 h) in stage 2 hypertension, and 14.6 µg/24 h (CI, 12.9 to 16.2 µg/24 h) in resistant hypertension; corresponding adjusted prevalence estimates for biochemically overt primary aldosteronism were 11.3% (CI, 5.9% to 16.8%), 15.7% (CI, 8.6% to 22.9%), 21.6% (CI, 16.1% to 27.0%), and 22.0% (CI, 17.2% to 26.8%). The aldosterone-renin ratio had poor sensitivity and negative predictive value for detecting biochemically overt primary aldosteronism. LIMITATION: Prevalence estimates rely on arbitrary and conventional thresholds, and the study population may not represent nationwide demographics. CONCLUSION: The prevalence of primary aldosteronism is high and largely unrecognized. Beyond this categorical definition of primary aldosteronism, there is a prevalent continuum of renin-independent aldosterone production that parallels the severity of hypertension. These findings redefine the primary aldosteronism syndrome and implicate it in the pathogenesis of "essential" hypertension. PRIMARY FUNDING SOURCE: National Institutes of Health.

The epistemology of modality and the problem of modal epistemic friction.

There are three theories in the epistemology of modality that have received sustained attention over the past 20 years (1998-2018): conceivability-theory, counterfactual-theory, and deduction-theory. In this paper we argue that all three face what we call the problem of modal epistemic friction (PMEF). One consequence of the problem is that for any of the three accounts to yield modal knowledge, the account must provide an epistemology of essence. We discuss an attempt to fend off the problem within the context of the internalism versus externalism debate about epistemic justification. We then investigate the effects that the PMEF has on reductive and non-reductive theories of the relation between essence and modality.