Prevalence and clinical characteristics of primary aldosteronism in a tertiary-care center in Korea

Comparative Analysis of Liquid Chromatography-Tandem Mass Spectrometry and Radioimmunoassay in Determining Plasma Aldosterone Concentration and Plasma Renin Activity for Primary Aldosteronism Screening

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) accurately measures plasma aldosterone concentration (PAC), but its correlation with radioimmunoassay (RIA), equivalent RIA levels, and optimal cutoff for PAC and aldosterone-to-renin ratio (ARR) in primary aldosteronism (PA) screening have not been determined in a Korean population. Our study of 127 patients who underwent diagnostic testing for PA showed that the LC-MS/MS and RIA methods have good correlation, with a mean bias of 29.3% for PAC. An LC-MS/MS PAC level of 11.7 ng/dL was equivalent to an RIA PAC level of 15 ng/dL. Receiver operating characteristic curve analysis showed that an LC-MS/MS PAC level of 10.3 ng/dL and LC-MS/MS ARR level of 20.0 provided sensitivity of 73.1% with a specificity of 57.3% and sensitivity of 92.3% with a specificity of 14.7%, respectively. When the LC-MS/MS method is used for PA screening, an adjustment of cutoff values is necessary.

Antihypertensive effects and changes in extracellular water content by mineralocorticoid receptor antagonists in patients with primary aldosteronism

In primary aldosteronism (PA), non-suppressible excessive aldosterone secretion due to dietary salt intake significantly contributes to hypertension and cardiovascular complications. Blocking the overactivation of mineralocorticoid receptors (MRs) with mineralocorticoid receptor antagonists (MRAs) is a cornerstone for the medical treatment of PA. However, the role of MRAs in controlling hypertension remains unclear. This study aimed to explore the relationship between changes in body composition parameters (determined by bioelectrical impedance analysis), blood pressure (BP) levels, serum potassium (K+) levels and Study 36-Item Short-Form Health Survey (SF-36) scores after MRA treatment in 50 patients with PA. Treatment with MRAs significantly decreased the systolic BP (SBP) and diastolic BP (DBP) levels and extracellular water (ECW) volume, while it increased the serum K+ levels, active renin concentrations (ARCs), and scores on several SF-36-based quality of life (QOL) subscales. ECW change (ΔECW) and serum K+ change were not significantly associated with changes in SBP and DBP levels. ΔECW showed a significant inverse correlation with ΔARC, suggesting that ARC increases with decreasing ECW volume due to renal MR activity blockade and that ARC is a highly sensitive indicator of ECW volume. In the stratified analysis of patients with PA, ECW volume was significantly decreased in those aged ≥60 years and those with a body mass index of ≥25 kg/m2. In conclusion, MRA treatment showed antihypertensive, biochemical, and QOL improvement effects in patients with PA. The antihypertensive effect may not be related to the decrease in ECW volume due to renal MR activity blockade. Evaluation of ECW using BIA in patients with PA treated with MRAs. Abbreviations: ARC, active renin concentration; BIA, bioelectrical impedance analysis; BMI, body mass index; BP, blood pressure; ECW, extracellular water; K+, serum potassium; MRA, mineralocorticoid receptor antagonist; PA, primary aldosteronism; QOL; quality of life; Δ, parameter changes after MRA treatment.

Development of a diagnostic model for pre-washout screening of primary aldosteronism

PURPOSE

Primary aldosteronism (PA) diagnosis is affected by antihypertensive drugs that are commonly taken by patients with suspected PA. In this study, we developed and validated a diagnostic model for screening PA without drug washout.

METHODS

We retrospectively analyzed 1095 patients diagnosed with PA or essential hypertension. Patients were randomly grouped into training and validation sets at a 7:3 ratio. Baseline characteristics, plasma aldosterone concentration (PAC), and direct renin concentration (DRC) before and after drug washout were separately recorded, and the aldosterone-to-renin ratio (ARR) was calculated.

RESULTS

PAC and ARR were higher and direct renin concentration was lower in patients with PA than in patients with essential hypertension. Furthermore, the differences in blood potassium and sodium concentrations and hypertension grades between the two groups were significant. Using the abbreviations potassium (P), ARR (A), PAC (P), sodium (S), and hypertension grade 3 (3), the model was named PAPS3. The PAPS3 model had a maximum score of 10, with the cutoff value assigned as 5.5; it showed high sensitivity and specificity for screening PA in patients who exhibit difficulty in tolerating drug washout.

CONCLUSION

PA screening remains crucial, and standard guidelines should be followed for patients to tolerate washout. The PAPS3 model offers an alternative to minimize risks and enhance diagnostic efficiency in PA for those facing washout challenges. Despite its high accuracy, further validation of this model is warranted through large-scale clinical studies.

Unique characteristics of Asians with hypertension: what is known and what can be done?

Hypertension remains the leading modifiable risk factor for cardiovascular disease worldwide. Over the past 30 years, the prevalence of hypertension has been increasing in East and Southeast Asia to a greater extent as compared with other Western countries. Asians with hypertension have unique characteristics. This can be attributed to increased impact of obesity on Asians with hypertension, excessive salt intake and increased salt sensitivity, loss of diurnal rhythm in blood pressure and primary aldosteronism. The impact of hypertension on cardiovascular (particularly strokes) and chronic kidney disease is greater in Asians. These unique characteristics underpinned by the diverse socioeconomic backgrounds pose its own challenges in the diagnosis and management of hypertension in Asia.

Temporal trends in clinical features of patients with primary aldosteronism over 20 years

Primary aldosteronism (PA) accounts for approximately 5-10% of hypertension cases. Over the past 20 years, the reported incidence of PA has increased due to widespread screening for secondary hypertension and imaging studies. We aimed to evaluate the temporal trends in the clinical characteristics and subtypes of PA. A total of 1064 patients with PA in two tertiary hospitals between 2000 and 2021 were categorized into three groups according to the year of diagnosis: 2000-2009, 2010-2015, and 2016-2021. The clinical characteristics of the patients over the three time periods were compared using a trend analysis. The age at diagnosis and sex of patients with PA did not change over 20 years. The proportion of patients with bilateral hyperaldosteronism (BHA) increased (11%, 25%, and 40%, P for trend <0.001). The proportion of hypokalemia (87%, 61%, and 40%) and plasma aldosterone concentration (36.0, 30.8, and 26.6 ng/dL) decreased (all P for trend <0.001). There was a trend toward an increased proportion of incidentally detected patients compared to clinically symptomatic patients (36%, 55%, and 61%, P for trend <0.001). The concordance rate of imaging and adrenal venous sampling results decreased (91%, 70%, and 57% P for trend <0.001). However, the proportion of patients with resistant hypertension and comorbidities did not differ. In conclusion, among patients with PA, patients with BHA and incidental detection have increased over 20 years, and more patients are likely to present with milder clinical symptoms and biochemical profiles.

The prevalence of metabolic syndrome in primary aldosteronism and essential hypertension: A systematic review and meta-analysis

It remained debates on metabolic-related disorders in patients with primary aldosteronism (PA) and essential hypertension (EH). A systematic review and meta-analysis was conducted to explore the prevalence of metabolic syndrome (MS) and the related indicators in PA and EH. PubMed, Embase, Web of Science and the Cochrane Central Register of Controlled Trials from their commencement to December 2023 were searched for eligible studies. The meta-analysis was performed by Review Manager 5.3 and STATA 15.1 software. A total of 12 studies were included, revealing that there was no significant difference between PA and EH in the prevalence of MS (1.27[0.92, 1.76], p = 0.14) with higher heterogeneity (I2 = 68%, p = 0.0002), while it became significant different (1.45[1.17, 1.81], p = 0.0008) and lower heterogeneity (I2 = 26%, p = 0.19) in patients who were overweight or obese by subgroup analysis. Higher systolic blood pressure (2.99[0.67, 5.31], p = 0.01; I2 = 43%, p = 0.06) and diastolic blood pressure (2.10[0.82, 3.38], p = 0.001; I2 = 36%, p = 0.11) with lower heterogeneity, and lower triglyceride in PA group with higher heterogeneity (-0.23[-0.37, -0.09], p = 0.001; I2 = 76%, p < 0.0001) were observed. No significant difference was found in other indicators. This study showed a higher prevalence of MS in patients who were overweight or obese with PA. However, it was not the same in these patients who were in normal weight. More researches were needed to explore the relationship between PA and metabolism of glucose and lipid.

Investigating the cut-off values of captopril challenge test for primary aldosteronism using the novel chemiluminescent enzyme immunoassay method: a retrospective cohort study

The measurement evolution enabled more accurate evaluation of aldosterone production in hypertensive patients. However, the cut-off values for novel assays have been not sufficiently validated. The present study was undertaken to validate the novel chemiluminescent enzyme immunoassay for aldosterone in conjunction with other methods. Moreover, we also aimed to establish a new cut-off value for primary aldosteronism in the captopril challenge test using the novel assay. First, we collected 390 plasma samples, in which aldosterone levels measured using liquid chromatography-mass spectrometry ranged between 0.18 and 1346 ng/dL. The novel chemiluminescent enzyme immunoassay showed identical correlation of plasma aldosterone with liquid chromatography-mass spectrometry, in contrast to conventional radioimmunoassay. Further, we enrolled 299 and 39 patients with primary aldosteronism and essential hypertension, respectively. Plasma aldosterone concentrations measured using the novel assay were lower than those measured by radioimmunoassay, which resulted in decreased aldosterone-to-renin ratios. Subsequently, positive results of the captopril challenge test based on radioimmunoassay turned into "negative" based on the novel assay in 45% patients with primary aldosteronism, using the conventional cut-off value (aldosterone-to-renin activity ratio > 20 ng/dL per ng/mL/h). Receiver operating characteristic curve analysis demonstrated that aldosterone-to-renin activity ratios > 8.2 ng/dL per ng/mL/h in the novel assay was compatible with the conventional diagnosis (sensitivity, 0.874; specificity, 0.980). Our study indicates the great measurement accuracy of the novel chemiluminescent enzyme immunoassay for aldosterone, and the importance of measurement-adjusted cut-offs in the diagnosis of primary aldosteronism.

Comparisons of risk factors for post-treatment renal dysfunction between the two major subtypes of primary aldosteronism

OBJECTIVE

Aldosterone-producing adenoma (APA) and bilateral idiopathic hyperaldosteronism (IHA) are the most common subtypes of primary aldosteronism (PA), and the PA subtype dictates the treatment options. This study aimed to identify predictors of declined estimated glomerular filtration rate (eGFR) following each treatment in patients with APA and IHA.

METHODS

We retrospectively investigated 45 patients with APA who had undergone adrenalectomy (ADX) and 37 patients with IHA who had received treatment with a mineralocorticoid receptor antagonist (MRA) to identify pre-treatment risk factors for eGFR decline during the post-treatment follow-up period.

RESULTS

Patients with APA who underwent ADX exhibited higher eGFR declines than patients with IHA treated with MRA at the 6-month post-treatment evaluation point. A high preoperative plasma aldosterone concentration (PAC) in patients with APA and a high body mass index (BMI) in patients with IHA were identified as independent predictors of higher eGFR decline at 6 months post-treatment (β=0.42 and β=0.36, respectively). In patients with APA, the cutoff PAC to best predict a 20% decrease in eGFR following ADX, as determined by receiver operating characteristic analysis, was 524 pg/mL. In patients with IHA, the cutoff BMI to best predict a 10% decrease in eGFR following MRA administration was 25.3 kg/m2. In addition, lower preoperative flow-mediated vasodilation was associated with eGFR decline after ADX in patients with APA.

CONCLUSIONS

Greater attention should be given to the above-mentioned risk factors to prevent renal impairment following each treatment in patients with both APA and IHA.

Kidney function predicts new-onset cardiorenal events and mortality in primary aldosteronism: approach of the 2021 race-free eGFR equation

Individuals with primary aldosteronism (PA) exhibit glomerular hyperfiltration, which may conceal underlying kidney damage. This observational cohort study enrolled 760 coronary artery disease-naive patients diagnosed with PA between January 1, 2007 and December 31, 2018 (male, 45%; mean age, 52.3 ± 11.9 years). The baseline estimated glomerular filtration rate (eGFR) was calculated using the 2021 Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, which includes serum creatinine and cystatin C but omits the race variable. During a mean follow-up of 5.8 ± 3.2 years, new-onset composite cardiovascular events (total death, non-fatal myocardial infarction, and coronary revascularization procedure) occurred at a crude incidence rate of 10.9 per 1,000 person-years. Multivariable Cox proportional hazards analysis showed that baseline eGFR was independently associated with composite cardiovascular events (hazard ratio [HR], 0.98 [95% CI, 0.97-0.99]). Penalized splines smoothing in multivariable regression analysis demonstrated that the risk of composite cardiovascular events increased negatively and linearly when patients had a baseline eGFR less than 85 mL/min/1.73 m2. Patients with baseline eGFR <85 mL/min/1.73 m2 were independently associated with higher risks of composite cardiovascular events (HR, 2.39 [95% CI, 1.16-4.93]), all-cause mortality (HR, 4.63 [95% CI, 1.59-13.46]), and adverse kidney events (sub-distribution HR, 5.96 [95% CI, 3.69-9.62], with mortality as a competing risk). Our data support baseline eGFR as a predictor for new-onset adverse cardiorenal events and emphasizes the importance of the early detection of kidney function impairment in hypertensive patients with PA. We also firstly validate the 2021 race-free CKD-EPI eGFR equation in Asian patents with PA. Even with the glomerular hyperfiltration phenomenon, baseline eGFR in patients with primary aldosteronism is associated with subsequent cardiorenal outcomes. The results also firstly point to the validity of the 2021 race-free CKD-EPI eGFR equation in healthcare and clinical decision-making.

2023 Korean Endocrine Society Consensus Guidelines for the Diagnosis and Management of Primary Aldosteronism

Primary aldosteronism (PA) is a common, yet underdiagnosed cause of secondary hypertension. It is characterized by an overproduction of aldosterone, leading to hypertension and/or hypokalemia. Despite affecting between 5.9% and 34% of patients with hypertension, PA is frequently missed due to a lack of clinical awareness and systematic screening, which can result in significant cardiovascular complications. To address this, medical societies have developed clinical practice guidelines to improve the management of hypertension and PA. The Korean Endocrine Society, drawing on a wealth of research, has formulated new guidelines for PA. A task force has been established to prepare PA guidelines, which encompass epidemiology, pathophysiology, clinical presentation, diagnosis, treatment, and follow-up care. The Korean clinical guidelines for PA aim to deliver an evidence-based protocol for PA diagnosis, treatment, and patient monitoring. These guidelines are anticipated to ease the burden of this potentially curable condition.