Diabetes Mellitus Itself Increases Cardio-Cerebrovascular Risk and Renal Complications in Primary Aldosteronism

CONTEXT

The prevalence of diabetes mellitus (DM) in patients with primary aldosteronism (PA) is higher than in those with essential hypertension and the general population. Although DM is a common major risk factor for cardio-cerebrovascular (CCV) diseases and renal complications, details of its effects in PA have not been demonstrated.

OBJECTIVE

The aim of this study was to determine the effects of coexistent DM on the risk of CCV events and progression of renal complications in PA patients.

DESIGN

A multi-institutional, cross-sectional study was conducted.

PATIENTS AND METHODS

PA patients experienced between January 2006 and October 2016 and with available data of CCV events and DM were enrolled from the Japan PA registry of the Japan Primary Aldosteronism Study/Japan Rare Intractable Adrenal Diseases Study (n = 2524). CCV events and renal complications were compared between a DM group and a non-DM group by logistic and liner-regression analysis.

RESULTS

DM significantly increased the odds ratio (OR) of CCV events (OR 1.59, 95% CI: 1.05-2.41) and that of proteinuria (OR 2.25, 95% CI: 1.59-3.16). DM correlated significantly with declines in estimated glomerular filtration rate (β = .05, P = .02).

CONCLUSIONS

This the first report to demonstrate the presence of DM as an independent risk factor for CCV events and renal complications, even in PA patients. Management of DM should be considered in addition to the specific treatment of PA.

Associations Between Changes in Plasma Renin Activity and Aldosterone Concentrations and Changes in Kidney Function After Treatment for Primary Aldosteronism

Introduction

Greater reduction in estimated glomerular filtration rate (eGFR) after specific treatment for primary aldosteronism (PA) reflects improvement in glomerular hyperfiltration associated with PA and leads to better patient outcomes. However, little is known regarding the mechanisms underlying eGFR reduction after treatment for PA.

Methods

We analyzed data from the nationwide PA registry in Japan. Patients were assigned to adrenalectomy (n = 438) and mineralocorticoid receptor (MR) antagonist (n = 746) groups. We assessed associations between changes in blood pressure (BP), plasma renin activity (PRA) and plasma aldosterone concentrations (PAC), and eGFR before and 6 months after treatment for both groups.

Results

In a multivariable linear regression, the adjusted β values (95% confidence interval [CI]) for change in eGFR after treatment were −2.76 (−4.29, −1.22) ml/min per 1.73 m² for PRA (per 3.2 ng/ml per hour), and 1.97 (1.08, 2.85) ml/min per 1.73 m² for PAC (per 236.1 pg/ml) in the adrenalectomy group; and −0.45 (−0.89, −0.01) ml/min per 1.73 m² for PRA and −0.72 (−1.62, 0.18) ml/min per 1.73 m² for PAC in the MR antagonist group. Change in mean arterial pressure after treatment was not significantly associated with change in eGFR in either group. Changes in PRA and PAC but not BP before and 6 months after treatment for PA were associated with greater reductions in eGFR.

Conclusion

Post-treatment improvements in glomerular hyperfiltration may be attributable to decreased MR activity in the kidneys, but not to reductions in systemic BP.

Age, Gender, and Body Mass Index as Determinants of Surgical Outcome in Primary Aldosteronism

Although unilateral primary aldosteronism (PA) should be curable by adrenalectomy (ADX), postsurgical outcome is affected by several clinical factors. Herein we reviewe the importance of age, gender, and BMI as determinants of surgical success based on the recent findings including a nation-wide, multicenter study in Japan (JPAS/JRAS). It is important to determine whether ADX for elderly patients with unilateral PA is as beneficial as younger patients. JPAS/JRAS showed that ADX could benefit elderly patients (>65 years) with definitive unilateral PA in curing of disease and improvement of hypertension, although potential adverse outcomes including hyperkalemia and renal insufficiency need to be considered in some elderly patients at high risk. As shown in previous studies, JPAS/JRAS also demonstrated that female gender was an independent predictor for clinical cure after ADX in patients with unilateral PA. The gender-specific predominance of somatic mutations of aldosterone-producing adenoma and sex hormones with vasculo-protective effects might account for the difference of surgical outcome between genders. Additionally, lower body mass index (BMI) has been shown to be one of the predictive factors for better clinical outcome after ADX. The relation between BMI and surgical outcome is, however, independent from aldosterone, since BMI does not correlate with PAC in PA. Early diagnosis of PA and lifestyle modification including weight control are essential to improve the surgical outcome of the unilateral PA. Thus, clinical practice guideline should include sophisticated strategy of ADX considering not only subtype diagnosis by adrenal venous sampling but also age, gender, and BMI to predict better surgical outcome.

Nadir Aldosterone Levels After Confirmatory Tests Are Correlated With Left Ventricular Hypertrophy in Primary Aldosteronism

Left ventricular hypertrophy (LVH) is often seen in patients with primary aldosteronism (PA), and the prevalence of LVH is reportedly higher among patients with PA than patients with essential hypertension. However, the correlation between aldosterone levels and LVH is undefined, and how aldosterone affects LVH in patients with PA remains unclear. We, therefore, retrospectively assessed a large PA database established by the multicenter JPAS (Japan Primary Aldosteronism Study) to reveal the factors associated with LVH in patients with PA without suspected autonomous cortisol secretion. In the 1186 patients with PA studied, the basal plasma aldosterone concentration, plasma renin activity, and the aldosterone-to-renin ratio did not significantly correlate with left ventricular LV mass index (LVMI) in single or multiple regression analyses. However, the plasma aldosterone concentration after the captopril challenge test or saline-infusion test, which are associated with autonomous aldosterone secretion, correlated significantly with LVMI, even after adjusting for patients’ backgrounds, including age and blood pressure. In addition, hypokalemia and the unilateral subtype also correlated with LVMI. Longitudinal subanalysis of medically or surgically treated patients with PA showed significant reductions in LVMI in both the surgery (63.0±18.1 to 55.3±19.5 g/m 2.7 , P <0.001) and drug treatment (56.8±14.1 to 52.1±13.5 g/m 2.7 , P <0.001) groups. Our results suggest the autonomous aldosterone secretion level, not the basal aldosterone level itself, is relevant to LVH in patients with PA. In addition, the elevated LVMI seen in patients with PA is at least partially reversible with surgical or medical treatment.

MON-198 Cosyntropin Stimulation on Adrenal Venous Sampling Obscure Surgically Curable Primary Aldosteronism

Context: While it has been shown that ACTH stimulation during adrenal venous sampling (AVS) for primary aldosteronism (PA) leads to correct lateralization, others showed opposite results. Whether to use ACTH stimulation during AVS for the subtype diagnosis of PA remains unsolved. Objectives: Our purpose of this study is to evaluate the clinical implications of ACTH stimulation during AVS in terms of surgical outcomes. Design and settings: Among JRAS cohort, we allocated 314 patients with both basal and ACTH-stimulated AVS data who underwent adrenalectomy to 3 groups: basal lateralization index (LI)≥2 with ACTH-stimulated LI ≥4 on the ipsilateral side (Unilateral (U) to U group, n=245); basal LI &lt;2 with ACTH-stimulated LI ≥4 (n=15); basal LI≥2 with ACTH-stimulated LI &lt;4 (U to Bilateral (B) group, n=54). We compared surgical outcomes among the groups. Results: Compared with the U to U group, the U to B group had poor clinical and biochemical outcomes and low rates of adrenal adenoma as a pathological finding. All patients in the U to Bgroup with clinical and biochemical benefits however had adrenal adenoma as a pathological finding and could be well differentiated from those with poor surgical outcome via basal LI, but not ACTH-stimulated LI. A receiver operating characteristic curve analysis demonstrated that the cut-off value of 8.3 showed the specificity of 84% for the prediction of good surgical outcome in U to B group.These results were similar even when we defined each group based on a cut-off value of 4 for basal LI. Although, the basal plasma aldosterone concentration (PAC) in the adrenal veins on both dominant and non-dominant sides among patients with better surgical outcome in the U to B group were not significantly different from those in the U to U group, there was a significant difference in the ACTH-stimulated PAC on the dominant side. Conclusions: We demonstrated novel findings showing that patients in the U to B group were shown to be comprised of 2 groups with good and poor surgical outcomes, and basal LI was useful in identifying PA patients with good surgical outcome in U to B group. The low expression level of MC2R receptor on aldosterone-producing adenoma (APA) might be the explanation of the weak response in aldosterone level in a proportion of surgically curable APA cases. These findings point to the important fact that ACTH stimulation on AVS obscure surgically curable cases of PA.

OR34-04 Efficiency of Adrenal Venous Sampling in the Treatment Choice of Primary Aldosteronism (AVSTAT Study)

BACKGROUND: Adrenal venous sampling (AVS) is strongly recommended for a subtype diagnosis of primary aldosteronism (PA) if adrenalectomy (ADX) is desired by the patient. Given various issues related to AVS such as technical demand, invasive nature, expensive cost and radiation exposure, AVS is expected to lead efficiently to the subtype diagnosis and ADX. Aim: Primary objective was to assess the performance of AVS to determine treatment of PA by investigating the ratio of unilateral disease and rate of ADX following AVS in patients with unilateral disease. Methods: Sixteen major referral centers in ENS@T (n=10) and Japan (n=6) participated in the study. Study period was from 2006 to 2018. Data on total number of PA patients, AVS (total number and number of successful procedures), number of patients with unilateral diseases, and number of patients that underwent ADX were collected by a questionnaire-based survey. In addition, reasons for not proceeding to ADX in patients with a unilateral diagnosis were investigated. The diagnosis of PA was based on the positive case detection and at least one positive result in confirmatory testing. Results: Total number of confirmed PA patients and conducted AVS showed a dramatic increase during the past decade (PA: 1061 pts/ 2006–2011 to 3718 pts/ 2012–2018; AVS: 720/ 2006–2011 to 2448/ 2012–2018). Success rate of AVS was improved from 79.0% (2006–2011) to 92.5% (2012–2018). Both rate of unilateral PA and ADX of successful procedures decreased from 42.7% (2006–2011) to 37.3% (2012–2018) and from 40.8% (2006–2011) to 34.9% (2012–2018), respectively. Of the patients with successful AVS, bilateral disease was diagnosed in 63.5% (1812/2854 pts). Of the unilateral PA patients, 11.9% (125/ 1054 pts) were not subjected to ADX. The rate of the patients not subjected to ADX was significantly higher in Japan than in ENS@T centers both in patients with successful AVS (75.8% vs. 53.4%) and with unilateral disease (19.9% vs. 8.6%). Clinical decision against ADX in unilateral disease was made by the physicians in 33.3%, the patients in 33.3%, and both in 33.3%. Medical factors for Dr.’s decision against ADX in unilateral disease included good blood pressure control, normokalemia, comorbidities (e.g. DM, CKD), non-lateralized CT findings (e.g. no tumor, contralateral tumor), and discordant results among different criteria of AVS.

Conclusions: High prevalence of bilateral disease and change of treatment policy after implementation affected the efficiency of AVS as an essential diagnostic procedure prior to ADX. Development of non-invasive procedures to exclude bilateral PA and more strict indication of AVS are warranted.

Effect of cosyntropin during adrenal venous sampling on subtype of primary aldosteronism: analysis of surgical outcome

OBJECTIVES

We investigated the clinical significance of ACTH stimulation during adrenal venous sampling (AVS) by surgical outcome of primary aldosteronism (PA).

DESIGN

Multicenter retrospective study by Japan PA study.

METHOD

We allocated 314 patients with both basal and ACTH-stimulated AVS data who underwent adrenalectomy to three groups: basal lateralization index (LI) ≥2 with ACTH-stimulated LI ≥4 on the ipsilateral side (Unilateral (U) to U group, n = 245); basal LI <2 with ACTH-stimulated LI ≥4 (Bilateral (B) to U group, n = 15); and basal LI ≥2 with ACTH-stimulated LI <4 (U to B group, n = 54). We compared surgical outcomes among the groups using the Primary Aldosteronism Surgical Outcome (PASO) criteria.

RESULTS

Compared with U to U group, U to B group had poor clinical and biochemical outcomes and low rates of adrenal adenoma as pathological findings (P = 0.044, 0.006, and 0.048, respectively), although there were no significant differences between U to U and B to U groups. All patients in U to B group with clinical and biochemical benefits, however, had adrenal adenoma as pathological findings and could be well differentiated from those with poor surgical outcomes via basal LI (>8.3), but not ACTH-stimulated LI. These results were similar even when we defined each group based on a cut-off value of 4 for basal LI.

CONCLUSIONS

Although PA patients in U to B group had worse surgical outcomes than did those in U to U group, basal LI could discriminate among patients with better surgical outcomes in U to B group.

Basal Plasma Aldosterone Concentration Predicts Therapeutic Outcomes in Primary Aldosteronism

Purpose

Normal basal plasma aldosterone concentration (PAC) reflects mild aldosterone excess compared to high basal PAC. We previously reported lower risk for cardiovascular and cerebrovascular events in patients with primary aldosteronism (PA) and normal basal PAC (nPA) than in those with high basal PAC (hPA). However, the differences in therapeutic outcomes between nPA and hPA are unclear. The aim of this multi-institutional, retrospective cohort study was to determine the clinical significance of nPA to therapeutic outcomes, including adrenalectomy (ADX) and treatment with mineralocorticoid receptor antagonists (MRAs).

Methods

A total of 1146 patients with PA who were diagnosed and underwent adrenal venous sampling (AVS) between January 2006 and October 2016 were enrolled. The clinical parameters at baseline and after ADX or treatment with MRA were compared between the nPA and hPA groups.

Results

Significantly higher rates of absent clinical success (36.6 vs. 21.9%, P = 0.01) and absent biochemical success (26.4 vs. 5.2%, P < 0.01) were found for the nPA group than for the hPA group, respectively. Logistic regression analysis identified baseline PAC as a significant independent predictor of absent clinical success of ADX and MRAs.

Conclusions

Plasma aldosterone concentration at baseline was a significant and independent predictor of absent clinical success of ADX and MRA. Mineralocorticoid receptor antagonist treatment appeared to be a better therapeutic choice than ADX in the nPA group.

Correlation between urinary fractionated metanephrines in 24-hour and spot urine samples for evaluating the therapeutic effect of metyrosine: a subanalysis of a multicenter, open-label phase I/II study

We recently conducted an open-label phase I/II study to evaluate the efficacy and safety of preoperative and chronic treatment with metyrosine (an inhibitor of catecholamine synthesis) in pheochromocytoma/paraganglioma (PPGL) in Japan. We compared creatinine-corrected metanephrine fractions in spot urine and 24-hour urine samples (the current standard for the screening and diagnosis of PPGLs) from 16 patients to assess the therapeutic effect of metyrosine. Percent changes from baseline in urinary metanephrine (uMN) or normetanephrine (uNMN) were compared between spot and 24-hour urine samples. Mean percent changes in uMN or uNMN in spot and 24-hour urine were -26.36% and -29.27%, respectively. The difference in the percent change from baseline between uMN or uNMN in spot and 24-hour urine was small (-2.90%). The correlation coefficient was 0.87 for percent changes from baseline between uMN or uNMN measured in spot and 24-hour urine. The area under the receiver operator characteristic (ROC) curve of uMN or uNMN measured in spot urine vs. 24-hour urine (reference standard) to assess the efficacy of metyrosine treatment was 0.93. Correlations and ROCs between 24-hour urinary vanillylmandelic acid, adrenaline, and noradrenaline and 24-hour uMN or uNMN were similar to those between spot uMN or uNMN and 24-hour uMN or uNMN. No large difference was observed between spot and 24-hour urine for the assessment of metyrosine treatment by quantifying uMN or uNMN in Japanese patients with PPGLs. These results suggest that spot urine samples may be useful in assessing the therapeutic effect of metyrosine.

Latent Autonomous Cortisol Secretion From Apparently Nonfunctioning Adrenal Tumor in Nonlateralized Hyperaldosteronism

CONTEXT

Adrenal tumors (ATs), even those diagnosed as nonfunctioning, may cause metabolic disorders. Some primary aldosteronism (PA) patients with ATs are diagnosed with bilateral PA based on adrenal venous sampling (AVS), and their ATs are apparently nonfunctioning.

OBJECTIVE

To clarify the influence of apparently nonfunctioning ATs, we compared hormone levels and clinical complications between bilateral PA cases with and without ATs.

DESIGN, SETTING, AND PARTICIPANTS

After retrospectively assessing 2814 patients with PA in the multicenter Japan PA study, bilateral PA cases on AVS were divided into cases with and without ATs by computed tomography findings. Importantly, patients with cortisol levels >1.8 µg/dL after the 1-mg dexamethasone suppression test (DST) were excluded. Clinical characteristics and biochemical data were compared between them. The correlation between AT size and hormone levels was also analyzed.

MAIN OUTCOME MEASURES

Analyzed were 196 bilateral PA patients with ATs and 331 those without ATs. Although basal cortisol and aldosterone levels were similar between them, cortisol levels after the 1-mg DST and the prevalences of diabetes mellitus and proteinuria were significantly higher and ACTH levels and plasma renin activity were significantly lower in cases with ATs than in those without. After adjusting for patients' backgrounds, cortisol levels after the 1-mg DST and plasma renin activity remained significantly different between them. Moreover, cortisol levels after the 1-mg DST and ACTH levels correlated with AT size.

CONCLUSIONS

Apparently nonfunctioning ATs in bilateral PA cases may cause latent autonomous cortisol secretion, inducing diabetes and proteinuria.

Renal impairment is closely associated with plasma aldosterone concentration in patients with primary aldosteronism

OBJECTIVE

Several clinical studies have reported that renal impairments are sometimes observed in patients with primary aldosteronism (PA). We analyzed the prevalence of renal impairments in PA patients and identified parameters that increase the risk for them.

DESIGN

This is a retrospective cross-sectional study. We assessed the PA database established by the multicenter Japan PA study (JPAS). Data were also collected from patients with essential hypertension (EHT).

METHODS

We compared the prevalences of proteinuria and lowered estimated glomerular filtration rate (eGFR) between patients with PA and age, sex, blood pressure and duration of hypertension-matched patients with EHT. We also performed logistic regression analysis to identify parameters that increase the risk for these renal impairments.

RESULTS

Among 2366 PA patients, the prevalences of proteinuria and lowered eGFR were 10.3 and 11.6%, respectively. The prevalence of proteinuria was significantly higher in PA patients than matched-EHT patients (16.8 vs 4.4%), whereas there was no significant difference in the prevalence of lowered eGFR (17.2 vs 15.0%). The logistic regression analysis also showed that the plasma aldosterone concentration (PAC) significantly increases the risk of proteinuria and lowered eGFR, independent of other known risk factors.

CONCLUSION

Plasma aldosterone levels are closely associated with renal impairment in patients with PA. This is contrast to our earlier finding that the PAC was not itself linearly associated with cardiovascular events such as stroke or ischemic heart disease. The mechanism underlying the kidney damage in patients with PA may differ from that affecting the cardiovascular system.

Predictors of Clinical Success After Surgery for Primary Aldosteronism in the Japanese Nationwide Cohort

Context

Aldosterone-producing adenomas are a curable subtype of primary aldosteronism (PA); however, hypertension persists in some patients after adrenalectomy.

Objective

To identify factors associated with, and develop prediction models for, blood pressure (BP) normalization or improvement after adrenalectomy.

Design

Retrospective analysis of patients treated between 2006 and 2018, with a 6-month follow-up.

Setting

A nationwide, 29-center Japanese registry encompassing 15 university hospitals and 14 city hospitals.

Patients

We categorized 574 participants in the Japan Primary Aldosteronism Study, who were diagnosed with PA and underwent adrenalectomy, as BP normalized or improved, on the basis of their presentations at 6 months postsurgery.

Main Outcome Measure

The rate of complete, partial, and absent clinical success. Predictive factors related to BP outcomes after PA surgery were also evaluated.

Results

Complete clinical success was achieved in 32.6% and partial clinical success was achieved in 53.0% of the patients at 6 months postsurgery. The following five variables were independent predictors for BP normalization: ≤7 years of hypertension, body mass index ≤25 kg/m², no more than one antihypertensive medication, absence of medical history of diabetes, and female sex. The area under the receiver operator characteristic curve was 0.797 in the BP normalization model.

Conclusion

We established models that predicted postoperative BP normalization in patients with PA. These should be useful for shared decision-making regarding adrenalectomy for PA.

ARMC5 Alterations in Primary Macronodular Adrenal Hyperplasia (PMAH) and the Clinical State of Variant Carriers

Context

Primary macronodular adrenal hyperplasia (PMAH) is a rare type of Cushing or subclinical Cushing syndrome and is associated with bilateral multinodular formation. ARMC5 is one of the responsible genes for PMAH.

Objectives

This study was performed to identify the genotype-phenotype correlation of ARMC5 in a cohort of Japanese patients.

Patients and Methods

Fourteen patients with clinically diagnosed PMAH and family members of selected patients were studied for ARMC5 gene alteration and clinical phenotype. The associated nonadrenal tumor tissues were also studied.

Results

Of fourteen patients with PMAH, 10 had pathogenic or likely pathogenic variants of ARMC5. We found two variants. Five unrelated patients had identical variants (p.R619*). In two patients, the variant was found in offspring with the asymptomatic or presymptomatic state. Six of ten patients who tested positive for the ARMC5 pathogenic or likely pathogenic variant carried nonadrenal tumors; however, no loss of heterozygosity (LOH) or second hit of the ARMC5 gene was evident. The ARMC5 variant–positive group showed a significantly higher basal cortisol level. Furthermore, age-dependent cortisol hypersecretion was seen in the ARMC5 variant–positive group.

Conclusions

ARMC5 pathogenic variants are common (71%) in Japanese patients with PMAH. p.R619* might be a hot spot in Japanese patients with PMAH. Asymptomatic or presymptomatic pathogenic variant carriers were found among the family members of the patients. Although 50% of ARMC5 variant carriers had nonadrenal neoplastic lesions, no LOH or second hit of ARMC5 in the tumor tissues was evident. The ARMC5 variant–positive mutant group showed a higher basal cortisol level than the negative group.

Association Between Acute Fall in Estimated Glomerular Filtration Rate After Treatment for Primary Aldosteronism and Long-Term Decline in Renal Function

Primary aldosteronism causes renal structural damage after glomerular hyperfiltration, and primary aldosteronism-specific treatment leads to an acute fall in estimated glomerular filtration rate (eGFR). We investigated whether this change affected the long-term eGFR slope in a retrospective cohort from the multicenter Japan Primary Aldosteronism Study. We allocated patients with primary aldosteronism to the adrenalectomy (n=202) and MR (mineralocorticoid receptor) antagonist (n=303) groups based on their treatment history and analyzed the association between the initial eGFR fall and long-term eGFR slope. The increased age, low serum potassium levels, high eGFR, and high plasma aldosterone levels were independent predictors for a large initial eGFR fall in both groups. Our analysis of tertiles based on the initial eGFR fall revealed that in the MR antagonist group, patients with a small initial eGFR fall had a significantly steeper long-term eGFR slope than those with a large initial fall (tertile 1 versus 2, P=0.025; tertile 1 versus 3, P=0.017). These associations were not identified in the adrenalectomy group. Thus, the smaller the acute fall in eGFR by initiation of MR antagonists, the greater was the rate of long-term eGFR decline. While the acute fall in eGFR induced by primary aldosteronism-specific treatment is occasionally a clinical concern, our findings highlight the favorable implications of the acute fall with respect to long-term renal outcomes.

Sex Difference in the Association Between Subtype Distribution and Age at Diagnosis in Patients With Primary Aldosteronism

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. Adrenal vein sampling (AVS) is an established method for finding patients with the unilateral subtype of PA, for which adrenalectomy is an applicable treatment. In this study, we analyzed a large database of patients with PA who underwent adrenal vein sampling, to investigate the sex differences in the impact of age at diagnosis on the subtype and cause of PA. In 2122 patients, women with the unilateral subtype were younger than men with the same subtype and women with the bilateral subtype. Younger age and older age were associated with unilateral PA in women and men, respectively. After stratification by tertiles of age, there was a trend of decreased and increased incidence of unilateral PA with aging in women and men, respectively. Male sex was a predictor of unilateral PA in middle-aged and older patients but not in younger patients. We also found that obesity, a known factor associated with idiopathic hyperaldosteronism, was positively associated with bilateral PA in younger patients but not in older patients. These findings suggest that the proportion of operable patients with unilateral PA differs depending on the combination of sex and age, and that other than obesity, the cause of PA is also associated with the bilateral subtype in older patients.

Lateralizing Asymmetry of Adrenal Imaging and Adrenal Vein Sampling in Patients With Primary Aldosteronism

Context

In patients with primary aldosteronism (PA), it remains unclear whether aldosterone-producing adenomas are likely to develop in the left or right adrenal gland.

Objective

To investigate left-right differences of PA laterality diagnoses via CT imaging and adrenal vein sampling (AVS).

Design

Retrospective, observational study.

Patients

From the Japan Primary Aldosteronism Study, 1493 patients with PA were enrolled who underwent CT and ACTH-stimulated AVS.

Measurements

Left or right adrenal nodular lesion distribution and laterality observed on CT scans and from AVS were noted.

Results

Both on CT scans and AVS, unilateral results were observed more frequently on the left side than on the right side (25.1% vs 15.4% and 17.3% vs 13.5%, respectively; P < 0.01for both diagnostic techniques). There was no significant difference in the concordance rate for CT and AVS between patients with left and right unilateral nodular lesions observed on CT scans (44.1% and 50.9%, respectively; P = 0.15). In patients with nodules <20 mm, the concordance rate was significantly greater on the right side than the left side (45.8% vs 56.4%; P = 0.03). In patients with bilateral results of AVS, unilateral nodular lesions were detected more frequently on the left side than the right side (17.8% vs 9.4%; P < 0.01).

Conclusion

These results suggest aldosterone-producing adenomas and nonfunctioning tumors are more likely to develop on the left side in patients with PA and that misdiagnosis of CT-based lateralization may occur more frequently on the left side.

High Prevalence of Diabetes in Patients With Primary Aldosteronism (PA) Associated With Subclinical Hypercortisolism and Prediabetes More Prevalent in Bilateral Than Unilateral PA: A Large, Multicenter Cohort Study in Japan

OBJECTIVE

To investigate the prevalence and causes of diabetes in patients with primary aldosteronism (PA) in a multi-institutional cohort study in Japan.

RESEARCH DESIGN AND METHODS

The prevalence of diabetes was determined in 2,210 patients with PA (diagnosed or glycated hemoglobin [HbA_1c] ≥6.5% [≥48 mmol/mol]; NGSP) and compared with that of the Japanese general population according to age and sex. In 1,386 patients with PA and clear laterality (unilateral or bilateral), the effects of plasma aldosterone concentration (PAC), hypokalemia (<3.5 mEq/L), suspected subclinical hypercortisolism (SH; serum cortisol ≥1.8 µg/dL after 1-mg dexamethasone suppression test), and PA laterality on the prevalence of diabetes or prediabetes (5.7% ≤ HbA_1c <6.5% [39 mmol/mol ≤ HbA_1c <48 mmol/mol]) were examined.

RESULTS

Of the 2,210 patients with PA, 477 (21.6%) had diabetes. This prevalence is higher than that in the general population (12.1%) or in 10-year cohorts aged 30-69 years. Logistic regression or χ² test revealed a significant contribution of suspected SH to diabetes. Despite more active PA profiles (e.g., higher PAC and lower potassium concentrations) in unilateral than bilateral PA, BMI and HbA_1c values were significantly higher in bilateral PA. PA laterality had no effect on the prevalence of diabetes; however, the prevalence of prediabetes was significantly higher in bilateral than unilateral PA.

CONCLUSIONS

Individuals with PA have a high prevalence of diabetes, which is associated mainly with SH. The prevalence of prediabetes is greater for bilateral than unilateral PA, suggesting a unique metabolic cause of bilateral PA.

SAT-LB066 Clinical Characteristics of Incidentally Discovered Functioning Adrenal Tumors: Study of Advancing Care and Pathogenesis of Intractable Adrenal Diseases in Japan (ACPA-J)

Objectives: Pheochromocytoma and paraganglioma (PPGL), Cushing syndrome (CS), bilateral macronodular adrenal hyperplasia (BMAH) and adrenocortical carcinoma (ACC) are rare adrenal tumors. Hence, collaboration of researchers and clinicians from several institutes and constructing patient registry are important to achieve progress in clinical management. We organized a research group and constructed a patient registry system for adrenal tumors named Advancing Care and Pathogenesis of Intractable Adrenal Diseases in Japan (ACPA-J). In the present study, we focused on incidentally discovered adrenal tumors despite the functioning tumors in ACPA-J database, and investigated their clinical characteristics. Subjects and methods: Clinical data of 176 patients with PPGL, 110 patients with CS, 38 patients with BMAH and 45 patients with ACC who were diagnosed 2006-2016 were registered to ACPA-J database by August 2018. Among the patients who have hormone excess confirmed by endocrinological evaluation, we analyzed the clinical characteristics of an incidentaloma (I) group and a non-incidentaloma (non-I) group in which their tumors were found based on signs and symptoms of adrenal disease, and compared those between two groups. Results: The hormone excess was confirmed in 162 patients with PPGL, 110 patients with CS, 38 patients with BMAH and 36 patients with ACC. Of those, 53.2% of PPGL, 36.7% of CS, 76.5% of BMAH and 24.5% of ACC were incidentaloma, respectively. Age in I group was higher in PPGL, CS and ACC compare to that in non-I group. Tumor size was larger in I group than that in non-I group only in ACC. Incidences of metabolic complications (hypertension, glucose intolerance and hyperlipidemia) were not different between two groups in all type of tumor. In PPGL, urine metanephrine levels and normetanephrine levels were not different between two groups. In CS and BMAH, morning plasma (p-) ACTH levels and p-cortisol levels in the morning, the midnight and after dexamethasone suppression test were not different between two groups. A rate of patients with subclinical cortisol excess was 13% in I group and 14% in non-I group in BMAH, whereas that in I group (50%) was higher than that in non-I group (23%) in ACC. Conclusions: The adrenal incidentaloma is defined as the tumor unexpectedly found during work-up for an indication unrelated to suspected adrenal disease. Most of the functioning adrenal tumors accompany signs and symptoms of hormone excess and have to be discovered in the process of work-up for adrenal disease. Our result showed there was not particular difference in characteristics between the incidentalomas and the non-incidentalomas. It was suggested that adrenal functioning tumors could be frequently overlooked. (This research was supported by AMED; JP18ek0109352, the Grant for NCGM; 30-A-1008, Health Labour Sciences Research Grant 2018.) Unless otherwise noted, all abstracts presented at ENDO are embargoed until the date and time of presentation. For oral presentations, the abstracts are embargoed until the session begins. Abstracts presented at a news conference are embargoed until the date and time of the news conference. The Endocrine Society reserves the right to lift the embargo on specific abstracts that are selected for promotion prior to or during ENDO.

SUN-144 High Prevalence of Diabetes in Patients with Primary Aldosteronism (PA) Associated with Subclinical Hypercortisolism and Prediabetes More Prevalent in Bilateral Than Unilateral PA

INTRODUCTION: Primary aldosteronism (PA) is characterized by the autonomous production of aldosterone, usually from an aldosterone producing adenoma in one adrenal gland or idiopathic hyperaldosteronism, with bilateral adrenal lesions. It has been suggested that aldosterone overproduction, hypokalemia, or the complication of subclinical hypercortisolism (SH) in patients with PA, are related to impaired glucose homeostasis and insulin resistance. However, the true contributions of these factors to disturbances of carbohydrate metabolism in PA have not been investigated thoroughly from a large-scale epidemiologic viewpoint. In the present study, the true prevalence of glucose intolerance in more than 2000 patients with PA and its association with aldosterone concentration, hypokalemia, and SH were studied in a multicenter collaborative study. METHODS: The prevalence of diabetes was determined in 2210 patients with PA (diagnosed or HbA_1c ≥6.5%, NGSP) and compared with that of the Japanese general population from the National Survey of the Ministry of Health, Labour and Welfare in 2016, according to age and sex. In 1386 patients with PA and clear laterality (unilateral or bilateral), the effects of plasma aldosterone concentration (PAC), hypokalemia (<3.5 mEq/L), suspected SH (serum cortisol ≥1.8 μg/dL after 1-mg dexamethasone suppression test) and PA laterality on the prevalence of diabetes or prediabetes (5.7%≤HbA_1c<6.5%) were examined. RESULTS: Of the 2210 patients with PA, 477 (21.6%) had diabetes, this prevalence of being higher than that of the general population (12.1%) or in 10 year cohorts aged 30 to 69 years. According to the χ² test, diabetes was present significantly more frequently in PA patients with suspected SH (26.8%) than in those with F-1mgDST <1.8 μg/dL (16.9%; p=0.001). When using logistic regression analysis, it was found that age, sex, BMI, and F-1mgDST ≥1.8 μg/dL were significant contributing factors to the presence of diabetes, whereas laterality of PA was not a significant factor. Despite more active PA profiles (e.g. higher PAC, lower potassium concentrations) in unilateral than bilateral PA, BMI and HbA_1c values were significantly higher in bilateral PA. PA laterality had no effect on prevalence of diabetes; however, prevalence of prediabetes was significantly higher in bilateral than unilateral PA. CONCLUSIONS: Individuals with PA have a high prevalence of diabetes, which is associated mainly with SH. The prevalence of prediabetes is greater for bilateral than unilateral PA, suggesting a unique metabolic cause of bilateral PA. SUPPORT: This research was supported by the Japan Agency for Medical Research and Development (AMED) for the Practical Research Project for Rare/Intractable Disease.

SAT-062 National PA Registry as a Platform for Standardized Clinical Practice of Primary Aldosteronism in Japan

Background: Primary aldosteronism (PA) is a representative cause of endocrine hypertension characterized by an excess production of aldosterone, hypertension, and cardiovascular complications. Although clinical practice guidelines have been published, diagnostic steps have not been standardized and heterogeneous clinical practice between centers remain to be the major issue of public health in Japan. Aim: To develop PA registry and to produce evidence for clinical practice of PA. Methods: PA registry was developed by Japan PA Study (JPAS) as one of the Incurable Disease Platform Project by the Japan Agency of Medical Research and Development (AMED) and the Ministry of Health, Labor and Welfare in Japan. 2850 PA patients who underwent AVS between 2006 and 2016 in 28 referral centers were registered. Major clinical questions were selected. Results: Evidence produced was as follows. 1) Prevalence of cardiovascular diseases was higher in PA than essential hypertension. Hypokalemia, unilateral subtype and/or PAC greater than 12.5ng/dl were at greater risk of cardiovascular diseases. 2) Since clinical manifestation of PA in elderly was similar to that in younger patients, diagnostic process should essentially follow the same steps. 3) Saline infusion test as a confirmatory test was also useful for subtype diagnosis. 4) More than 90% of PA patients with normokalemia and bilateral disease on CT had bilateral subtype on AVS and needed AVS less weakly. Those aged more than 35 yrs. with marked PA could be spared AVS. 5) While biochemical benefit after ADX was achieved solely with LI greater than 4 of AVS, clinical benefit was largely affected by clinical findings such as age, BMI, and blood pressure. 6) Since prevalence of cortisol co-secretion was high in PA with adrenal tumor smaller than 2cm, DEX suppression test was mandatory. LI greater than 4 was applicable for PA subtype diagnosis even in patients with cortisol co-secretion, but not in those with overt Cushing syndrome. 7) ADX provided superior results in correcting hypertension and hypokalemia than medication in unilateral PA. Conclusions: National PA registry was developed for standardized clinical practice of PA in Japan. Various evidence for elaboration and simplification of clinical practice guideline of PA was created by excluding institutional bias. The PA registry has started to be operated as a part of more comprehensive registry by Japan Rare Adrenal Disease Study (JRAS) for a sustainable platform of future research and development. (Supported by AMED for the Practical Research Project for Rare/Intractable Disease under Grant Number JP17ek0109122; JP18ek0109352).

Obesity as a Key Factor Underlying Idiopathic Hyperaldosteronism

CONTEXT

Recently, the relationship between primary aldosteronism (PA) and various metabolic disorders, including obesity, diabetes mellitus, and dyslipidemia, has been discussed. However, in PA, aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) have different etiologies.

OBJECTIVE

Our objectives were to clarify differences in obesity and metabolic disorders between APA and IHA and to gain insight in the pathogenesis of IHA.

DESIGN, SETTING, AND PARTICIPANTS

This is a retrospective cross-sectional study. We assessed the PA database established by the multicenter Japan Primary Aldosteronism Study. For comparative analysis, data were also collected from 274 patients with essential hypertension (EHT).

MAIN OUTCOME MEASURES

We compared prevalences of obesity and metabolic disorders between patients with APA and patients with IHA. Comparisons with sex-, age-, and blood pressure-matched patients with EHT were also performed. Correlations between metabolic parameters and plasma aldosterone concentrations (PACs) in each subtype were analyzed.

RESULTS

Analysis of 516 patients with APA and 1015 patients with IHA revealed PACs were significantly higher in patients with APA than patients with IHA. By contrast, after we adjusted for clinical backgrounds, the prevalence of obesity was significantly higher in patients with IHA than in patients with APA or EHT. Although the prevalences of diabetes mellitus and dyslipidemia did not significantly differ between patients with IHA and patients with APA, triglyceride and HbA1c were significantly higher in patients with IHA than in patients with APA. There was no significant correlation between metabolic parameters and PACs in either subtype.

CONCLUSIONS

Patients with IHA tend to be obese despite lower PACs than in patients with APA. The present results suggest that obesity-related factors contribute to the pathogenesis of IHA.

Clinical Characteristics and Postoperative Outcomes of Primary Aldosteronism in the Elderly

CONTEXT

Primary aldosteronism (PA) in the elderly has increased in importance in association with population aging.

OBJECTIVE

To investigate the characteristics and outcomes of elderly patients with PA undergoing adrenalectomy.

PATIENTS AND METHODS

Using a database of patients with PA who underwent adrenal venous sampling (AVS), we compared elderly patients (≥65 years old) with nonelderly patients (<65 years old) in terms of characteristics, subtype classification in ACTH-stimulated AVS, and outcomes after adrenalectomy.

RESULTS

The elderly group had a higher prevalence of comorbidities than the nonelderly group. The proportion of the unilateral subtype [defined as a lateralization index (LI) >4] was comparable between the age groups. In patients who received adrenalectomy, biochemical cure was comparable between the groups, whereas persistent hypertension was more common in the elderly group. The prevalences of hyperkalemia and renal impairment (chronic kidney disease stage 3b or higher) were higher in the elderly group. Multiple regression analysis showed that the duration of hypertension predicted persistent hypertension and hyperkalemia and that preoperative estimated glomerular filtration rate predicted renal impairment in the elderly group. LI >4 in AVS was an independent predictor of biochemical cure after adrenalectomy in the elderly group but not in the nonelderly group. Age was negatively associated with biochemical cure in patients with LI ≤4.

CONCLUSION

Adrenalectomy contributes to biochemical improvement in elderly patients if determined in accordance with AVS. The treatment strategy should be determined considering the high postoperative incidence of persistent hypertension and hyperkalemia in elderly patients with a long history of hypertension or renal impairment in those with reduced renal function.

Correlation Between Lateralization Index of Adrenal Venous Sampling and Standardized Outcome in Primary Aldosteronism

Objectives

The aim of this study was to investigate the impact of adrenal venous sampling (AVS) lateralization cutoffs on surgical outcomes.

Patients and Methods

Cosyntropin-stimulated AVS was used to guide surgical management of 377 patients with primary aldosteronism (PA) who were evaluated 6 months after surgery.

Main Outcome Measures

The proportion of patients that achieved clinical benefit and complete biochemical success based on the AVS aldosterone lateralization index (LI) was determined.

Results

Clinical benefit was achieved in 29 of 47 patients with an LI between 2 and 4, in 66 of 101 with an LI between 4 and 10, and in 158 of 203 with an LI > 10 (P < 0.01 for trend). Complete biochemical success was achieved in 27 of 42 with an LI between 2 and 4, in 60 of 76 with an LI between 4 and 10, and in 127 of 155 with an LI > 10 (P = 0.024 for trend). After adjustment for confounders and using those patients with an LI between 2 and 4 as a reference, a clinical benefit was associated only with those with an LI > 10 (OR, 2.30; 95% CI, 1.03 to 5.16), whereas complete biochemical success was associated with those with an LI between 4 and 10 (OR, 2.83; 95% CI, 1.14 to 7.01) or LI > 10 (OR, 3.55; 95% CI, 1.47 to 8.55).

Conclusions

Difference of clinical outcome was relatively small when strict LI diagnostic threshold was used; biochemical cure was sufficiently achieved when an LI > 4 was used. Our study by standardized outcome measures validated that an LI > 4 may be appropriate for determining unilateral disease in PA.