Comparative analysis of aldosterone and renin assays for primary aldosteronism screening

The transition from radioimmunoassay (RIA) to chemiluminescent enzyme immunoassay (CLEIA) for plasma aldosterone concentration (PAC) assays has raised concerns over its impact on primary aldosteronism (PA) diagnosis. This study investigated the correlation between PAC and renin values using RIA, CLEIA, and liquid chromatography/mass spectrometry/mass spectrometry (LC-MS/MS), established cutoff values for PA diagnosis using the aldosterone-to-renin ratio (ARR) with PAC_CLEIA, and assessed the differences in PAC values by measuring weak mineralocorticoids (WMs). This retrospective study evaluated 312 serum PAC samples using RIA, CLEIA, and LC-MS/MS, and analyzed 315 plasma renin samples. Method correlations were assessed through Passing-Bablok regression. Receiver operating characteristic curves determined ARR cutoffs for PA diagnosis. WMs were quantified to evaluate their impact on ΔPAC (RIA-LC-MS/MS) through multiple regression analysis. PAC_CLEIA and PAC_LC-MS/MS values were highly correlated. ARRs derived from PAC_RIAs demonstrated more false positives and lower specificity than ARRs using PAC_CLEIA or PAC_LC-MS/MS. WMs significantly influenced ΔPAC in both the PA and non-PA groups. ARRs using PAC_CLEIA are valuable for determining PA cutoffs in clinical practice. The transition to PAC using CLEIA may enhance PA detection rates. WMs were found to interfere with PAC measurements in the RIA method, affecting outcomes.

Predictor of Steroid Replacement Duration after Removal of Cortisol-producing Adenoma

Objective Cortisol-producing adenoma (CPA) is a major subtype of functional adrenal tumors. CPAs are generally treated with adrenalectomy; however, it is difficult to predict the ideal duration of glucocorticoid replacement after resection. This study explored pre-operative factors predictive of glucocorticoid replacement therapy duration after CPA resection. Mehtods This multicenter retrospective observational study was conducted as part of the Advancing Care and Pathogenesis of Intractable Adrenal Diseases in Japan (ACPA-J) from January 2006 to December 2015. Patients This study was conducted at 10 referral centers and included 124 patients who received hydrocortisone replacement therapy after adrenalectomy for CPA. Results The median duration of replacement therapy was 12 (interquartile range, 5-24) months. In the single regression analysis, the sex (P=0.04), morning ACTH level (P=0.02), morning serum cortisol level (P=0.003), midnight serum cortisol level (P<0.001), serum cortisol level after a 1-mg dexamethasone suppression test (P<0.001), presence of lumbar compression fracture (P=0.015), and Cushingoid appearance (P<0.001) were all significantly associated with the replacement therapy duration. In multiple regression analyses, the midnight serum cortisol level and presence of lumbar compression fracture were significantly correlated with the replacement therapy duration after adjusting for other parameters. Conclusion Our results suggest that high midnight serum cortisol levels, which cause persistent suppression of the HPA axis, contribute to a delay in HPA axis recovery. Lumbar compression fracture is an important symptom that reflects the severity and persistence of cortisol secretion.

Differences in target organ damage between captopril challenge test-defined definitive-positive and borderline-range groups among patients with primary aldosteronism

The new Japanese guidelines for primary aldosteronism introduce a category in the judgment of functional confirmatory tests that is called the "borderline range," which is rare in the other international guidelines. The clinical characteristics of this borderline group are not yet understood. To investigate whether this borderline group has any significant differences in terms of target organ damage, we used data from a Japanese nationwide registry (JPAS-II) of individuals with primary aldosteronism or essential hypertension to compare the borderline group with the definitive-positive group and the negative group. We analyzed the cases of 1785 patients based on their captopril-challenge test results. Since the JPAS-II database contains plasma aldosterone concentration values obtained based on both radioimmunoassay (n = 1555) and chemiluminescent enzyme immunoassay (n = 230) principles, we converted these values to their equivalents as if measured by chemiluminescent enzyme immunoassay and conducted all analyses under the simulated condition. Multicovariate-adjusted models revealed significant prevalance odds ratios for chronic kidney disease (2.01, 95% confidence interval: 1.13 to 3.61), electrocardiographic abnormalities (1.66, 95% confidence interval: 1.16 to 2.37). No significant difference was observed between the borderline and negative groups in these assessments (odds ratio [95% confidence interval] for chronic kidney disease: 0.73 [0.26 to 2.02] and electrocardiographic abnormalities: 1.01 [0.60 to 1.70]). We confirmed that the prevalence of target organ damage increases linearly as the aldosterone-to-renin ratio rises following the captopril challenge test. These results provide material to consider regarding the significance of the provisionally established borderline group.

Primary aldosteronism patients with previous cardiovascular and cerebrovascular events have high aldosterone responsiveness to ACTH stimulation

Aldosterone secretion in primary aldosteronism (PA) is often regulated by adrenocorticotropic hormone (ACTH) in addition to its autonomous secretion. However, the clinical characteristics and risk of cardiovascular and cerebrovascular (CCV) events in PA patients with aldosterone responsiveness to ACTH stimulation remain unclear. This study aimed to investigate the prevalence of CCV events in PA patients with high aldosterone responsiveness to ACTH stimulation. A retrospective cross-sectional study was conducted as part of the Japan Primary Aldosteronism Study/Japan Rare Intractable Adrenal Disease project. PA patients with adrenal venous sampling (AVS) between January 2006 and March 2019 were enrolled. The ACTH-stimulated plasma aldosterone concentration (PAC) of the inferior vena cava during AVS was used to evaluate aldosterone responsiveness to ACTH. We analyzed the relationship between responsiveness and previous CCV events. Logistic regression analysis demonstrated that the ΔPAC (the difference between the PAC measurements before and after ACTH stimulation) significantly increased the odds of previous CCV events in PA patients after adjusting for classical CCV event risk factors, baseline PAC and duration of hypertension (relative PAC: odds ratio [OR], 2.896; 95% confidence interval [CI], 0.989-8.482; ΔPAC: OR, 2.344; 95% CI, 1.149-4.780; ACTH-stimulated PAC: OR, 2.098; 95% CI, 0.694-6.339). This study clearly demonstrated that aldosterone responsiveness to ACTH is closely related to previous CCV events. The responsiveness of the PAC to ACTH could be useful in predicting CCV event risk.Registration Number in UMIN-CTR is UMIN000032525.

A Case of Acute-Onset Type 1 Diabetes Mellitus with Diabetic Ketoacidosis Triggered by COVID-19

BACKGROUND It is well known that diabetes mellitus contributes to COVID-19 severity. Recently, there have been reports of an increase in the number of children with type 1 diabetes after the COVID-19 pandemic. CASE REPORT A 52-year-old woman presented to the Emergency Department with disturbance of consciousness, accompanied by a 1-day history of thirst, a fever of 38°C, and breathlessness. She had a positive coronavirus antigen test. Her initial vital signs assessment showed a heart rate of 120 beats per minute, blood pressure 90/50 mmHg, temperature 37.3°C, and respiratory rate 30 breaths/minute with an oxygen saturation of 100% with 10 L oxygen inhalation. Her initial laboratory test results showed a blood glucose level of 1507 mg/dl, HbA1c of 10.1%, ketone 2+, and blood gas pH 7.113. The patient was diagnosed with diabetic ketoacidosis (DKA). There were mild inflammatory findings with blood CRP 0.14 mg/dl and a white cell count of 12 400/μL, but no pneumonia on a chest CT scan. Therefore, the patient was diagnosed with COVID-19 and DKA. The patient was positive for anti-glutamic acid decarboxylase (anti-GAD antibody) and had markedly low levels 24-h urine C-peptide (CPR). She was diagnosed with acute-onset type 1 diabetes mellitus, as her blood examination showed a postprandial blood glucose level of 100 mg/dl and HbA1c of 5.7% 2 months before admission. After admission, fluid replacement and continuous intravenous insulin infusion therapy were started, and blood glucose and blood gas pH improved over 10 h. CONCLUSIONS There have been reports of cases of type 1 diabetes consequences of COVID-19, but the mechanism has not been elucidated.

Do multiple types of confirmatory tests improve performance in predicting subtypes of primary aldosteronism?

OBJECTIVE

The clinical practice guideline for primary aldosteronism (PA) places a high value on confirmatory tests to sparing patients with false-positive results in case detection from undergoing adrenal venous sampling (AVS). However, it is unclear whether multiple types of confirmatory tests are more useful than a single type. To evaluate whether the machine-learned combination of two confirmatory tests is more useful in predicting subtypes of PA than each test alone.

DESIGN

A retrospective cross-sectional study in referral centres.

PATIENTS

This study included 615 patients with PA randomly assigned to the training and test data sets. The participants underwent saline infusion test (SIT) and captopril challenge test (CCT) and were subtyped by AVS (unilateral, n = 99; bilateral, n = 516).

MEASUREMENTS

The area under the curve (AUC) and clinical usefulness using decision curve analysis for the subtype prediction in the test data set.

RESULTS

The AUCs for the combination of SIT and CCT, SIT alone and CCT alone were 0.850, 0.813 and 0.786, respectively, with no significant differences between them. The AUC for the baseline clinical characteristics alone was 0.872, whereas the AUCs for these combined with SIT, combined with CCT and combined with both SIT and CCT were 0.868, 0.854 and 0.855, respectively, with no significant improvement in AUC. The additional clinical usefulness of the second confirmatory test was unremarkable on decision curve analysis.

CONCLUSIONS

Our data suggest that patients with positive case detection undergo one confirmatory test to determine the indication for AVS.

A hyperaldosteronism subtypes predictive model using ensemble learning

This study aimed to develop a machine-learning algorithm to diagnose aldosterone-producing adenoma (APA) for predicting APA probabilities. A retrospective cross-sectional analysis of the Japan Rare/Intractable Adrenal Diseases Study dataset was performed using the nationwide PA registry in Japan comprised of 41 centers. Patients treated between January 2006 and December 2019 were included. Forty-six features at screening and 13 features at confirmatory test were used for model development to calculate APA probability. Seven machine-learning programs were combined to develop the ensemble-learning model (ELM), which was externally validated. The strongest predictive factors for APA were serum potassium (s-K) at first visit, s-K after medication, plasma aldosterone concentration, aldosterone-to-renin ratio, and potassium supplementation dose. The average performance of the screening model had an AUC of 0.899; the confirmatory test model had an AUC of 0.913. In the external validation, the AUC was 0.964 in the screening model using an APA probability of 0.17. The clinical findings at screening predicted the diagnosis of APA with high accuracy. This novel algorithm can support the PA practice in primary care settings and prevent potentially curable APA patients from falling outside the PA diagnostic flowchart.

Impact of a change to a novel chemiluminescent immunoassay for measuring plasma aldosterone on the diagnosis of primary aldosteronism

In Japan, the standard method for measuring plasma aldosterone concentration (PAC) for primary aldosteronism (PA) diagnosis was changed from radioimmunoassay (RIA) to a novel chemiluminescent enzyme immunoassay (CLEIA). The purpose of this study is to simulate the possible impact of the change on PA diagnosis. This retrospective study assessed 2,289 PA patients. PACs measured by conventional RIA were transformed to estimated PACs (CLEIA) as follows: RIA (pg/mL) = 1.174 × CLEIA (pg/mL) + 42.3. We applied the estimated PAC (CLEIA) to the conventional cut-off of aldosterone-to-renin activity ratio ≥200 for screening and captopril challenge test (CCT) and PAC ≥60 pg/mL for saline infusion test (SIT). Application of the estimated PAC to screening and confirmatory tests decreased the number of PA diagnoses by 36% (743/2,065) on CCT and 52% (578/1,104) on SIT (discrepant cases). Among the discrepant cases, 87% (548/628) of CCT and 87% (452/522) of SIT were bilateral on adrenal venous sampling (AVS). Surgically treatable aldosterone-producing adenomas (APAs) were observed in 6% (36/579) and 5% (23/472) of discrepant cases on CCT and SIT, respectively; most were characterized by hypokalemia and/or adrenal nodule on CT imaging. Application of the PAC measured by the novel CLEIA to conventional cut-offs decreases the number of PA diagnoses. Although most discrepant cases were bilateral on AVS, there are some APA cases that were characterized by hypokalemia and/or adrenal tumor on CT. Further studies which evaluate PACs measured by both RIA and CLEIA for each patient are needed to identify new cut-offs for PAC measured by CLEIA.

Effect of Intraprocedural Cortisol Measurement on ACTH-stimulated Adrenal Vein Sampling in Primary Aldosteronism

Context

Adrenocorticotropin (ACTH) loading is used to increase the success rate of adrenal vein sampling (AVS).

Objective

We aimed to determine the effect of intraprocedural cortisol measurement (ICM) on ACTH-stimulated AVS (AS-AVS) owing to a lack of reliable data on this topic.

Methods

This multicenter, retrospective, observational study took place in 28 tertiary centers in Japan. Among 4057 patients enrolled, 2396 received both basal AVS (B-AVS) and AS-AVS and were divided into 2 groups according to whether ICM was used. The effect of ICM on AS-AVS was measured.

Results

In patients who underwent both AVS procedures, the ICM group had significantly higher success rates for both B-AVS and AS-AVS than the non-ICM group did. However, the probability of failure of AS-AVS after a successful B-AVS and the probability of success of AS-AVS after a failed B-AVS were not significantly different in the 2 groups. For subtype diagnosis, propensity-score matching revealed no significant difference between the 2 groups, and the discrepancy rate between B-AVS and AS-AVS for subtype diagnosis was also not significantly different.

Conclusion

ICM significantly increased the success rate of B-AVS and AS-AVS in protocols in which both AVS procedures were performed and had no effect on subtype diagnosis. However, in protocols in which both AVS procedures were performed, the results suggest ICM may not be necessary when performing AS-AVS if ICM is used only when B-AVS is performed. Our study suggests that ICM during AVS plays an important role and should be recommended.

Association of cardiovascular disease risk and changes in renin levels by mineralocorticoid receptor antagonists in patients with primary aldosteronism

A recent report stated that patients with primary aldosteronism who remain renin suppressed during mineralocorticoid receptor antagonist treatment might have a higher risk of developing cardiovascular disease than those with unsuppressed renin activity. We retrospectively investigated the incidence of composite cardiovascular disease and risk factors for cardiovascular disease in 1115 Japanese patients with primary aldosteronism treated with mineralocorticoid receptor antagonists. The median follow-up period was 3.0 years, and the incidence of cardiovascular events was very low (2.1%) throughout 5 years of follow-up. Changes in plasma renin activity from before to after mineralocorticoid receptor antagonist treatment were divided into three groups based on tertile, low, intermediate, and high plasma renin activity change groups, with incidences of cardiovascular disease events of 2.1%, 0.5%, and 3.7%, respectively. Multivariate Cox regression analysis revealed age (adjusted hazard ratio, 1.07; 95% confidence interval, [1.02-1.12]) and body mass index (adjusted hazard ratio, 1.13 [1.04-1.23]) as independent risk factors for cardiovascular disease. The high plasma renin activity change group had significantly higher cardiovascular disease risk with mineralocorticoid receptor antagonist treatment than the intermediate plasma renin activity change group (adjusted hazard ratio, 5.71 [1.28-25.5]). These data suggest that a high change in renin level after mineralocorticoid receptor antagonist treatment may not necessarily predict a better prognosis of cardiovascular disease in patients with primary aldosteronism.

Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021

Primary aldosteronism (PA) is associated with higher cardiovascular morbidity and mortality rates than essential hypertension. The Japan Endocrine Society (JES) has developed an updated guideline for PA, based on the evidence, especially from Japan. We should preferentially screen hypertensive patients with a high prevalence of PA with aldosterone to renin ratio ≥200 and plasma aldosterone concentrations (PAC) ≥60 pg/mL as a cut-off of positive results. While we should confirm excess aldosterone secretion by one positive confirmatory test, we could bypass patients with typical PA findings. Since PAC became lower due to a change in assay methods from radioimmunoassay to chemiluminescent enzyme immunoassay, borderline ranges were set for screening and confirmatory tests and provisionally designated as positive. We recommend individualized medicine for those in the borderline range for the next step. We recommend evaluating cortisol co-secretion in patients with adrenal macroadenomas. Although we recommend adrenal venous sampling for lateralization before adrenalectomy, we should carefully select patients rather than all patients, and we suggest bypassing in young patients with typical PA findings. A selectivity index ≥5 and a lateralization index >4 after adrenocorticotropic hormone stimulation defines successful catheterization and unilateral subtype diagnosis. We recommend adrenalectomy for unilateral PA and mineralocorticoid receptor antagonists for bilateral PA. Systematic as well as individualized clinical practice is always warranted. This JES guideline 2021 provides updated rational evidence and recommendations for the clinical practice of PA, leading to improved quality of the clinical practice of hypertension.

Primary aldosteronism with mild autonomous cortisol secretion increases renal complication risk

OBJECTIVE

In primary aldosteronism (PA), renal impairment has been identified as an important comorbidity. Excess cortisol production also may lead to renal damage; thus, concomitant mild autonomous cortisol secretion (MACS) may predispose PA patients to renal disorders. However, there is limited evidence to support this claim. Therefore, this study aimed to determine whether the concurrence of MACS and PA increases the risk of renal complications.

DESIGN

This study is a retrospective cross-sectional study.

METHODS

A total of 1310 patients with PA were stratified into two groups according to 1 mg dexamethasone suppression test (DST) results (cut-off post-DST serum cortisol 1.8 µg/dL): MACS (n = 340) and non-MACS (n = 970). The prevalence of renal complications was compared between the group. We also performed multiple logistic regression analysis to determine factors that increase the risk for renal complications.

RESULTS

The prevalence of lowered estimated glomerular filtration rate (eGFR) and proteinuria was nearly twice higher in the MACS group than in the non-MACS group. Not only plasma aldosterone concentration (PAC) but also the presence of MACS was selected as independent factors that were associated with the two renal outcomes. The risk of lower eGFR or proteinuria in patients who had MACS and higher levels PAC was several folds higher than in those who had an absence of MACS and lower levels of PAC.

CONCLUSIONS

MACS is an independent risk factor for renal complications in patients with PA, and MACS concomitant with higher aldosterone secretion in PA patients causes an increase in the risk of developing renal complications.

Aldosterone-to-Renin Ratio Is Associated with Diabetic Nephropathy in Type 2 Diabetic Patients: A Single-Center Retrospective Study

BACKGROUND It is well established that primary aldosteronism (PA) and aldosterone-to-renin ratio (ARR) are associated with kidney disease. The aim of this study was to retrospectively investigate the relationship between ARR, urinary albumin excretion (UAE), and estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes from a single center. MATERIAL AND METHODS We included 70 patients with type 2 diabetes, UAE ≤100 mg/day, not taking renin-aldosterone system inhibitors, did not meet the diagnostic criteria for PA, and had an ARR <20. The patients were divided into 3 groups: the normal low (NL) group (33 patients) with a UAE <10 mg/day, the normal (N) group (22 patients) with a UAE of 10-29 mg/day, and the microalbuminuria (M) group (15 patients) with a UAE of 30-100 mg/day. The ARR, plasma renin activity (PRA), and plasma aldosterone (PAC) were compared among groups. RESULTS The ARR was highest in group M (10.1±4.6), 6.5±0.3 in group NL, and 7.0±2.7 in group N. The PRA and PAC were significantly lower in group M (P<0.001). The ARR showed a significant positive correlation with log UAE (r=0.37, P<0.001) and a significant negative correlation with eGFR (r=-0.33, P<0.01). CONCLUSIONS High levels of aldosterone relative to renin, which did not fulfill confirmatory criteria for PA, may be one of the risk factors for the development of diabetic nephropathy in patients with diabetes. The present results are supported by previous research showing that an increased ARR without PA was a risk factor for kidney disease.

Sex Difference in the Association of Osteoporosis and Osteopenia Prevalence in Patients with Adrenal Adenoma and Different Degrees of Cortisol Excess

OBJECTIVE

Osteoporosis and osteopenia (OS/OP) are frequent in patients with adrenal adenomas associated with cortisol excess (CE). However, the relationship between OS/OP and CE severity considering sex differences is unknown.

DESIGN

A cross-sectional observational study from January 2006 to December 2015. Patients. 237 patients with adrenal adenoma associated with CE, including Cushing's syndrome and mild autonomous cortisol secretion (MACS), diagnosed in 10 referral centers in Japan. MACS was defined by 1 mg overnight dexamethasone suppression test (DST) cortisol level >1.8 μg/dL. Measurements. Prevalence of fragility fractures, medication for osteoporosis, and bone mineral density.

RESULTS

In total, 112 of 237 patients, who were predominantly female (P < 0.001) and had lower BMI (P=0.013), had OS/OP. Patients with OS/OP was significantly affected by CE (P < 0.01) than those without. The adjusted odds ratio (OR) for predicting OS/OP was obtained in multivariate logistic regression analysis. Clinical measures of CE, 1 mg DST cortisol levels, were positively associated with OS/OP in total cases (OR 1.124, 95% CI: 1.070-1.181, P < 0.001) and the cases with MACS (OR 1.156, 95%CI: 1.046-1.278, P=0.005). A cutoff value of 1 mg DST cortisol level >5.0 μg/dL was associated with OS/OP differently between men and women. OS/OP risk in men with MACS was significantly affected only by 1 mg DST cortisol levels. However, OS/OP risk in women with MACS was significantly affected by 1 mg DST cortisol levels and age.

CONCLUSIONS

CE severity in adrenal adenoma is positively associated with OS/OP. However, the associated factors of OS/OP in the patients with MACS are different between men and women.

Subtype-specific trends in the clinical picture of primary aldosteronism over a 13-year period

OBJECTIVE

Primary aldosteronism has two main clinically and biologically distinct subtypes: unilateral aldosterone-producing adenoma (APA) and bilateral adrenal hyperplasia (BAH). We aimed to evaluate the changes of each subtype's clinical characteristics over a 13-year period.

METHODS

This retrospective study involved time-trend analyses to identify changes in the clinical features of APA and BAH at diagnosis (2006-2018). A nationwide database from 41 Japanese referral centers was searched, which identified 2804 primary aldosteronism patients with complete baseline information and adrenal venous sampling (AVS) data.

RESULTS

The proportion of patients with APA decreased from 51% in 2006-2009 to 22% in 2016-2018. Among the 1634 patients with BAH, trend analyses revealed decreases in hypertension duration (median 7--3 years; P < 0.01) and hypokalemia prevalence (18--11%; P < 0.01). However, among the 952 patients with APA, there were no significant changes in hypertension duration (median 8 years) and hypokalemia prevalence (overall 70%). Furthermore, the APA group had a trend towards increased use of multiple hypertensive drugs at diagnosis (30--43%; P < 0.01). When subtypes were reclassified according to the precosyntropin stimulation AVS data, APA patients tended to be diagnosed earlier and at milder forms, consistent with the trend in overall primary aldosteronism patients.

CONCLUSION

During 2006-2018, we identified marked subtype-specific trends in the clinical findings at the diagnosis of primary aldosteronism. Our results suggested that the emphasis on the implementing cosyntropin stimulation during AVS might lead to under-identification of APA, especially in patients with mild or early cases.

Pheochromocytoma and paraganglioma with negative results for urinary metanephrines show higher risks for metastatic diseases

PURPOSE

Few studies have assessed the clinical features of pheochromocytoma and paraganglioma (PPGL) not producing excessive catecholamine. We aimed to clarify the clinical characteristics of PPGL patients with negative results for urinary metanephrines.

METHODS

This is a retrospective cross-sectional study. We established a database by combining datasets from the Nationwide Cohort Study on the Development of Diagnosis and Treatment of Pheochromocytoma in Japan (PHEO-J) and the Advancing Care and Pathogenesis of Intractable Adrenal diseases in Japan (ACPA-J). We compared the clinical differences between PPGL patients with negative results for urinary metanephrines and those with catecholamine-producing PPGL.

RESULTS

Five hundred PPGL patients in the combined database were analyzed. Among them, 31 were negative for metanephrines. PPGL with negative results for urinary metanephrines was significantly associated with extra-adrenal disease (Odds ratio (OR) 6.58, 95% CI (confidence interval) 3.03-14.3, p < 0.001), the presence of metastatic disease (OR 4.22, 95% CI 1.58-11.3, p = 0.004), and negativity on meta-iodobenzylguanidine (MIBG) scintigraphy (OR 0.15, 95% CI 0.03-0.77, p = 0.023).

CONCLUSIONS

Our findings demonstrate that PPGL patients with negative results for urinary metanephrines are associated with extra-adrenal lesions, metastatic disease, and negative MIBG findings. This suggests that PPGL patients with negative results for urinary metanephrines have a greater need for systemic whole-body imaging other than MIBG scintigraphy and close follow-up to monitor for metastasis than do patients with PPGL overtly producing excessive catecholamine.

Mild Autonomous Cortisol Secretion in Primary Aldosteronism Enhances Renal and Hemorrhagic Cerebrovascular Complications

Background: It is well known that primary aldosteronism (PA) is often associated with renal dysfunction and cardiovascular events (CVEs). However, the synergic effect of mild autonomous cortisol secretion (MACS) on the co-morbidities among PA has not been clarified yet. Thus, we retrospectively assessed whether the presence of MACS in PA patients with adrenal tumor, which may have MACS, to enhance the risk of the complications using a large Japanese multicenter database.

Methods: We enrolled patients with both confirmed PA and obvious adrenal tumor (diameter > 1 cm) on computed tomography. The subtype of PA was diagnosed based on the results of adrenal venous sampling with ACTH stimulation. A total of 575 study subjects were stratified into two groups according to 1-mg dexamethasone suppression test (DST) results (cut-off post-DST serum cortisol 1.8 µg/dL): MACS group (N=174, 30.2%) and non-MACS group (N=401, 69.8%). Decreased estimated glomerular filtration rate (eGFR) was defined as <60 ml/min per 1.73m².

Results: The percentage of unilateral PA between the MACS and non-MACS group was equivalent (50.0% vs. 48.1%). Prevalence of decreased eGFR in the MACS group was higher than in the non-MACS group [odds ratio (OR) 1.91, 95% confidence interval (95% CI) 1.20–3.04, P=0.006]. Conversely, prevalence of MACS was higher in patients with decreased eGFR than those without decreased eGFR (42.7% vs 28.0%, P=0.008). Proteinuria was deteriorated with the increase in post-DST serum cortisol concentration as well as the basal plasma aldosterone concentration (PAC) (P=0.028 and P<0.001, respectively), although PAC but not the presence of MACS was selected as an independent factor related with decreased eGFR. Prevalence of cerebral hemorrhage in the MACS group was higher than the non-MACS group. (OR 5.35, 95%CI 1.83–15.6, P=0.002). We found that MACS was the only significant factor which increased the odds of developing cerebral hemorrhage (OR 9.13, 95%CI 2.15–38.90, P=0.003). Prevalence of other CVEs between the two groups was similar. Regardless of the PA subtype, complication rate of decreased eGFR and cerebral bleeding in the MACS group were significantly or tend to be higher than non-MACS group.

Conclusion: Our date strongly suggested that co-secretion of cortisol in PA directly and/or indirectly increase renal and cerebrovascular comorbidities. Given that MACS is common in PA, endocrinological testing with DST is recommended in PA patients, especially those with adrenal tumor on imaging. (Supported by Research Grants of AMED:JP17ek0109122, JP20ek0109352; National Center for Global Health and Medicine:27–1402, 30–1008), and Ministry of Health, Labour, and Welfare, Japan (046).

Association of aldosterone and blood pressure with the risk for cardiovascular events after treatments in primary aldosteronism

BACKGROUND AND AIMS

We used a dataset from a Japanese nationwide registry of patients with primary aldosteronism, to determine which of the parameters of hyperaldosteronism and blood pressure before or after treatments for primary aldosteronism (i.e., surgical adrenalectomy or a medication treatment) are important in terms of cardiovascular prognosis.

METHODS

We assessed whether plasma aldosterone-to-renin ratio and pulse pressure levels before treatment and 6 months after treatment were associated with composite cardiovascular disease events during the 5-year follow-up period.

RESULTS

The cohort included 1987 patients (mean age was 53.2 years, 52.0% were female, 37.2% had undergone surgical treatment, and the remainder had been treated with mineralocorticoid receptor antagonists). In the Cox proportional hazard model, the covariate-adjusted hazard ratio (95% confidence interval) for the composite cardiovascular disease events risk for each one-standard-deviation increase in the aldosterone-to-renin ratio or pulse pressure before treatment, those after treatment, or the duration of hypertension were 1.24 (1.05, 1.48), 0.74 (0.54, 1.02), and 1.07 (0.79, 1.44), 1.43 (1.07, 1.92), and 1.52 (1.19, 1.95), respectively. Patients with a high pre-treatment aldosterone-to-renin ratio of more than 603 and a large post-treatment pulse pressure of more than 49 mmHg showed approximately three-fold higher hazard ratios for cardiovascular events risk compared to those with a lower aldosterone-to-renin ratio and smaller pulse pressure.

CONCLUSIONS

Higher aldosterone-to-renin ratio before treatments, higher pulse pressure after treatments, and longer duration of hypertension were prognostic factors for cardiovascular diseases. Early intervention may be important for preventing cardiovascular disease among patients with primary aldosteronism.

Age-stratified comparison of clinical outcomes between medical and surgical treatments in patients with unilateral primary aldosteronism

Although adrenalectomy (ADX) is an established treatment for unilateral primary aldosteronism (uPA), the influence of age on the surgical outcomes is poorly understood. Therefore, we aimed to elucidate how age affects the clinical outcomes after treatments. We analyzed 153 older (≥ 65 years) and 702 younger patients (< 65 years) with uPA, treated either with ADX or mineralocorticoid receptor antagonist (MRA) in the Japan PA Study, and compared the estimated glomerular filtration rate (eGFR) or blood pressure over a 36-month period after treatments. ADX-treated patients showed severer biochemical indicators than MRA-treated patients. During 6 and 36 months, the eGFR decreased more prominently in older but not in younger patients with ADX than in those with MRA, which remained significant after adjustment with the inverse probability of treatment weighting (IPTW). There was a significant interaction between the age-groups and the treatment choices in the change of the eGFR with IPTW-adjusted analysis. The post-treatment dose of antihypertensive medication was lower in younger and higher in older patients with ADX than those with MRA. The clinical benefit of ADX differed between younger and older patients with uPA. These findings indicate the need for further validation on whether ADX can benefit older patients with uPA.

Adrenal Venous Sampling-Guided Adrenalectomy Rates in Primary Aldosteronism: Results of an International Cohort (AVSTAT)

CONTEXT

Adrenal venous sampling (AVS) is the current criterion standard lateralization technique in primary aldosteronism (PA). Japanese registry data found that 30% of patients with unilateral PA did not undergo adrenalectomy, but the reasons for this and whether the same pattern is seen internationally are unknown.

OBJECTIVE

To assess the rate of AVS-guided adrenalectomy across an international cohort and identify factors that resulted in adrenalectomy not being performed in otherwise eligible patients.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective, multinational, multicenter questionnaire-based survey of management of PA patients from 16 centers between 2006 and 2018.

MAIN OUTCOME MEASURES

Rates of AVS implementation, AVS success rate, diagnosis of unilateral PA, adrenalectomy rate, and reasons why adrenalectomy was not undertaken in patients with unilateral PA.

RESULTS

Rates of AVS implementation, successful AVS, and unilateral disease were 66.3%, 89.3% and 36.9% respectively in 4818 patients with PA. Unilateral PA and adrenalectomy rate in unilateral PA were lower in Japanese than in European centers (24.0% vs 47.6% and 78.2% vs 91.4% respectively). The clinical reasoning for not performing adrenalectomy in unilateral PA were more likely to be physician-derived in Japan and patient-derived in Europe. Physician-derived factors included non-AVS factors, such as good blood pressure control, normokalemia, and the absence of adrenal lesions on imaging, which were present before AVS.

CONCLUSION

Considering the various unfavorable aspects of AVS, stricter implementation and consideration of surgical candidacy prior to AVS will increase its diagnostic efficiency and utility.

A comparison of meal tolerance test and oral glucose tolerance test for predicting insulin therapy in patients with gestational diabetes

AIMS

To identify factors predicting a need for insulin therapy in gestational diabetes mellitus (GDM) by comparing plasma glucose (PG) levels in a 75-g oral glucose tolerance test (75-g OGTT) with those in a 500-kcal meal tolerance test (MTT) containing 75 g of carbohydrate.

SUBJECTS AND METHODS

The MTT was performed in 61 patients who diagnosed with GDM by a 75-g OGTT (age, 33.2 ± 4.5 years; prepregnancy body mass index, 22.6 ± 4.7 kg/m2; number of gestational weeks, 25.1 ± 6.4 weeks). PG and serum insulin levels were measured before the meal and up to 180 min after the meal. The insulin secretion capacity and resistance index were calculated.

RESULTS

PG levels increased from 86.8 ± 8.8 mg/dL at fasting to 132.7 ± 20.1 mg/dL at 30 min, and 137.8 ± 27.7 mg/dL at 60 min after MTT in the 35 patients with needed insulin therapy; these levels were significantly higher than those in the 26 patients, who only needed diet therapy. The patients with needed insulin therapy had significantly higher fasting PG levels in the 75-g OGTT, PG levels at fasting and 30 min after the MTT, and homeostasis model assessment of insulin resistance (HOMA-IR), and a significantly lower disposition index (DI) and insulin index than patients treated by diet alone. Receiver operating characteristic curve analysis was performed for factors involved in insulin therapy, with the following cutoff values: fasting PG in the 75-g OGTT, 92 mg/dL; PG 30 min after MTT, 129 mg/dL; HOMA-IR, 1.51; DI, 3.9; HbA1c, 5.4%. Multivariate analysis revealed that the 30-min PG level after MTT and HOMA-IR predicted insulin therapy.

CONCLUSION

PG levels at 30 min after MTT may be useful for identifying patients with GDM, who need insulin therapy.

Should Adrenal Venous Sampling Be Performed in PA Patients Without Apparent Adrenal Tumors?

INTRODUCTION

Some aldosterone-producing micro-adenomas cannot be detected through image inspection. Therefore, adrenal venous sampling (AVS) is often performed, even in primary aldosteronism (PA) patients who have no apparent adrenal tumors (ATs) on imaging. In most of these cases, however, the PA is bilateral.

OBJECTIVE

To clarify the clinical need for AVS in PA patients without apparent ATs, taking into consideration the rates of adrenalectomy.

METHODS

This is a retrospective cross-sectional study assessing 1586 PA patients without apparent ATs in the multicenter Japan PA study (JPAS). We analyzed which parameters could be used to distinguish unilateral PA patients without apparent ATs from bilateral patients. We also analyzed the prevalences of adrenalectomy in unilateral PA patients.

RESULTS

The unilateral subtype without an apparent AT was diagnosed in 200 (12.6%) of 1586 PA patients. Being young and female with a short hypertension duration, normokalemia, low creatinine level, low plasma aldosterone concentration, and low aldosterone-to-renin ratio (ARR) was significantly more common in bilateral than unilateral PA patients. If PA patients without apparent ATs were female and normokalemic with a low ARR (<560 pg/ml per ng/ml/h), the rate of unilateral PA was only 5 (1.1%) out of 444. Moreover, 77 (38.5%) of the 200 did not receive adrenalectomy, despite being diagnosed with the unilateral subtype based on AVS.

CONCLUSION

The low prevalence of the unilateral subtype in PA patients without apparent ATs suggests AVS is not indicated for all of these patients. AVS could be skipped in female normokalemic PA patients without apparent ATs if their ARRs are not high. However, AVS should be considered for male hypokalemic PA patients with high ARRs because the rates of the unilateral subtype are high in these patients.

Sex Differences in Renal Outcomes After Medical Treatment for Bilateral Primary Aldosteronism

A higher incidence of bilateral primary aldosteronism in women is reported. Treatment of bilateral primary aldosteronism usually involves mineralocorticoid receptor antagonists. However, the impact of sex on renal outcomes is unknown. We compared renal outcomes between the sexes after mineralocorticoid receptor antagonist initiation by analyzing data obtained from 415 female and 313 male patients with bilateral primary aldosteronism who were treated with spironolactone or eplerenone in the JPAS (Japan Primary Aldosteronism Study). Over the course of 5 years, the temporal reduction in the estimated glomerular filtration rate was greater in women than in men (P<0.001). Systolic blood pressure levels were equal between the sexes, despite higher doses of antihypertensive drugs in men. The mean of the annual decline in estimated glomerular filtration rate during what we termed the late phase, or 6 to 60 months after mineralocorticoid receptor antagonist initiation, was larger in women than in men after adjusting for patient characteristics (-1.33 mL/min per 1.73 m² per year versus -1.04 mL/min per 1.73 m² per year, P<0.01). Female sex was a significant predictor of greater annual decline during the late phase in patients taking spironolactone but not in those taking eplerenone. Spironolactone use and diabetes were independent predictors of a greater annual decline in estimated glomerular filtration rate during the late phase in women. These findings suggest that female sex is associated with poorer renal outcomes in patients receiving mineralocorticoid receptor antagonist for bilateral primary aldosteronism.

Obesity predicts persistence of resistant hypertension after surgery in patients with primary aldosteronism

OBJECTIVE

Primary aldosteronism (PA) is considered a major cause of resistant hypertension (RHT). The prevalence of RHT has been recently reported to reach 18% in general hypertension. However, little is known about the prevalence and the outcomes after adrenalectomy of RHT in PA. Therefore, we aimed to clarify the prevalence and surgical outcomes in patients with both PA and RHT.

PATIENTS AND DESIGN

Among 550 patients who underwent adrenalectomy for unilateral PA in the Japan PA Study, RHT was defined as an uncontrolled blood pressure (≥140/90 mm Hg) despite treatment with at least any three antihypertensives or hypertension controlled with at least four drugs. Surgical outcome was assessed by the biochemical and clinical outcome.

RESULTS

Although 40 (7.3%) patients fulfilled the criteria for preoperative RHT, this should be underestimated because only 36% of patients with postoperative RHT were classified as having preoperative RHT. The prevalence of preoperative RHT was approximately 20% when estimated using the total number of patients with postoperative RHT and the ratio of postoperative RHT in patients with preoperative RHT. Although an improvement in hypertension was achieved in approximately 80% of patients with preoperative RHT, 20% of these exhibited persistent RHT. These patients were more obese than those for whom RHT improved after surgery. Notably, body mass index of ≥25 kg/m² was an independent predictor of postoperative RHT.

CONCLUSIONS

The prevalence of RHT in PA was lower than expected even with the adjustment for underestimation. Furthermore, obesity is an independent factor predicting the postoperative persistence of RHT.