Type 2 diabetic patients with resistant hypertension should be screened for primary aldosteronism

Extra cut-off value of aldosterone-to-renin ratio for screening primary aldosteronism in hypertensive patients with diabetes mellitus

Primary aldosteronism (PA) and diabetes mellitus (DM) may coexist. We previously found that DM and impaired glucose tolerance (IGT) may decrease the efficiency of the aldosterone-to-renin ratio (ARR) for screening PA. Thus, we wanted to determine appropriate ARR cut-off values for screening PA in patients with hypertension with DM and IGT. Data from 736 patients with hypertension were collected. They were divided into PA (77 cases), PA with DM (27 cases), PA with IGT (44 cases), hypertension without PA (353 cases), hypertension with DM (without PA, 127 cases), and hypertension with IGT (without PA, 108 cases). Receiver operating characteristic (ROC) curves were used to identify the appropriate ARR cut-off values in different conditions. Screening efficiencies of these cut-off values were evaluated across different groups. ARR cut-off values for screening PA in hypertensive patients without DM and IGT, with DM, and with IGT were 29.65, 23.15, and 26.9, respectively. All cut-off values demonstrated high sensitivity and specificity: 92.2% and 88.7%, 92.6% and 79.5%, and 88.6% and 85.2%, respectively, and areas under the ROC curves were 0.941, 0.904, and 0.909, respectively. Our results suggest that extra ARR cut-off values may be necessary for effective screening PA in hypertensive patients with DM and IGT, particularly in those with DM.

Prevalence and impact of diabetes and prediabetes on presentation and complications of primary hyperaldosteronism at diagnosis

BACKGROUND

Primary hyperaldosteronism (PH) is considered to contribute to increased risk of developing type 2 diabetes mellitus (T2DM) and prediabetes. Both PH and DM are associated with increased risk for hypertension, cardiovascular diseases, and chronic kidney diseases. However, data on prevalence of T2DM and prediabetes in PH, and impact of T2DM and prediabetes on presentation and cardio renal complications in PH at presentation is sparse.

AIM

To determine the prevalence of T2DM and prediabetes in PH at diagnosis and impact on presentation and complications of PH.

METHODS

A retrospective cohort study was conducted in tertiary care settings in individuals with confirmed diagnosis of PH at presentation. Demographic variables, clinical presentations, duration and degree of hypertension, complications, laboratory parameters including sodium, potassium levels, plasma aldosterone concentration (PAC), plasma renin activity (PRA), and aldosterone to renin ratio (ARR) and cardio-renal parameters were collected. Comparison was done between three groups: PH with no DM (Group A) or with pre-diabetes (Group B) or with T2DM (Group C). P < 0.05 was statistically significant.

RESULTS

Among 78 individuals with confirmed PH, 62% had pre-diabetes or diabetes; with 37% having DM. Mean duration of T2DM was 5.97 ± 4.7 years. The mean levels of glycaemic parameters among the group A vs B vs C individuals were fasting plasma glucose (mg/dL): 87.9 ± 6.5, 105.4 ± 9.02, 130.6 ± 21.1; post prandial plasma glucose (mg/dL): 122.7 ± 9.8, 154.9 ± 14, 196.7 ± 38.0; glycated haemoglobin (%) (5.3 ± 0.2, 5.9 ± 0.2, 7.5 ± 0.6, P < 0.05), respectively. There was no significant difference in the biochemical parameters (PAC, PRA, ARR, sodium, potassium levels), presentation and complications between the groups. Cardio renal parameters or degree and duration of hypertension were comparable between the groups.

CONCLUSION

Significant prevalence of T2DM and prediabetes in PH at diagnosis does not impact its presentation or complications. Early screening for undetected PH in T2DM and prediabetes subjects with hypertension may prevent complications.

High Prevalence of Primary Aldosteronism in Patients with Type 2 Diabetes Mellitus and Hypertension

Primary aldosteronism (PA) is the most common cause of endocrine hypertension. The prevalence of hypertension is higher in patients with diabetes mellitus-2 (DM-2). Following the limited existing data, we prospectively investigated the prevalence of aldosterone excess either as autonomous secretion (PA) or as a hyper-response to stress in hypertensive patients with DM-2 (HDM-2). A total of 137 HDM-2 patients and 61 non-diabetics with essential hypertension who served as controls (EH-C) underwent a combined, overnight diagnostic test, the Dexamethasone–captopril–valsartan test (DCVT) used for the diagnosis of PA and an ultralow dose (0.3 μg) ACTH stimulation test to identify an exaggerated aldosterone response to ACTH stimulation. Twenty-three normotensive individuals served as controls (NC) to define the normal response of aldosterone (ALD) and aldosterone-to-renin ratio (ARR) to the ultralow dose ACTH test. Using post-DCVTALD and ARR from the EH-C, and post-ACTH peak ALD and ARR from the NC, 47 (34.3%) HDM-2 patients were found to have PA, whereas 6 (10.4%) HDM-2 patients without PA (DCVT-negative) exhibited an exaggerated aldosterone response to stress—a prevalence much higher than ever reported. Treatment with mineralocorticoid receptor antagonists (MRAs) induced a significant and permanent reduction of BP in all HDM-2 patients. Early diagnosis and targeted treatment of PA is crucial to prevent any aggravating effect on chronic diabetic complications.

Prevalence of primary aldosteronism in type 2 diabetes mellitus and hypertension: A prospective study from Western India

OBJECTIVE

Type 2 diabetes mellitus (T2DM) and hypertension commonly coexist; however, underlying primary aldosteronism (PA) can lead to worsening of hypertension, glycemia and cardiovascular risk. We aim to screen patients with T2DM and hypertension for PA by conducting a prospective monocentric study from Western India, which included adults with T2DM and hypertension from the outpatient diabetes clinic.

DESIGN

Prospective study.

PATIENTS AND MEASUREMENTS

Patients with an aldosterone renin ratio of ≥1.6 ng/dl/µIU/ml with plasma aldosterone concentration (PAC) ≥ 10 ng/dl were considered to be positive on a screening test. A PAC ≥ 6 ng/dl on seated saline suppression test (SST) was used to confirm the diagnosis of PA.

RESULTS

Four hundred and eighty-six patients were included in this study. Seventy-six (15.6%, 95% confidence interval [CI]: 12.7%-19.1%) patients had a positive screening test with positive confirmatory test in 20 of the 36 (55.5%, 95% CI: 39.3%-71.7%) screen-positive patients who underwent SST. Patients with positive screening test had a higher proportion of females (65.8% vs. 50%; p = .011), frequent history of hypertensive crises (21.1% vs. 8%; p = .001), uncontrolled blood pressure (51.3% vs. 34.6%; p = .006), diagnosis of hypertension before diabetes (32.9% vs. 21.7%; p = .035) and higher systolic (137.6 ± 6.9 vs. 131.2 ± 17.8 mmHg; p = .004) and diastolic (85.3 ± 11.1 vs. 81.7 ± 10.7 mmHg; p = .007) blood pressures. Patients with positive confirmatory test had longer duration of diabetes (108 [60-162] vs. 42 [24-87] months; p = .012), hypertension (84 [42-153] vs. 36 [15-81] months; p = .038) and higher creatinine (1.16 [1.02-1.42] vs. 0.95 [0.84-1.12] mg/dl; p = .021).

CONCLUSIONS

PA is prevalent (at least 4.1%) in Asian Indian patients with T2DM and hypertension. Further studies are needed to assess the cost-effectiveness of routine screening.

Screening for Primary Aldosteronism in the Diabetic Population: a cohort study

CONTEXT

Primary aldosteronism (PA) is the most common endocrine cause of hypertension. It is associated with higher cardio-metabolic risk than essential hypertension. Hypertension is common in patients with type 2 diabetes who carry increased cardiovascular risk, however, it is unknown how frequently they are tested for PA.

OBJECTIVE

The study aims to assess the extent to which the Endocrine Society's 2016 PA screening guidelines have been applied in a tertiary diabetes care setting and evaluate the demographic, clinical and biochemical characteristics of patients who met screening criteria compared to those who did not.

RESEARCH DESIGN & METHODS

This is a retrospective cohort study. Data were collected from 272 patients who attended tertiary Diabetes Clinics and had two or more blood pressure measurements from January to December 2018.

RESULTS

Of 272 patients, 63 (23.2%) had indication(s) for PA screening but only 15 (23.8% of 63) were screened using the aldosterone-to-renin ratio (ARR). Four patients who did not meet screening criteria were screened. Only one of 19 patients screened had an abnormal ARR, however 16 were taking medications known to affect aldosterone and/or renin production.

CONCLUSIONS

In a tertiary diabetes outpatient setting, only a minority of patients who fulfilled the Endocrine Society criteria for PA screening were actually screened. Appropriate screening for PA in the diabetic hypertensive population is necessary for the diagnosis and targeted treatment of a highly modifiable cardiovascular risk factor. Further studies are needed to develop feasible strategies to identify patients with PA in this population. This article is protected by copyright. All rights reserved.

Aldosterone-potassium ratio predicts primary aldosteronism subtype

OBJECTIVE

Prediction models have been developed to predict either unilateral or bilateral primary aldosteronism, and these have not been validated externally. We aimed to develop a simplified score to predict both subtypes and validate this externally.

METHODS

Our development cohort was taken from 165 patients who underwent adrenal vein sampling (AVS) in two Asian tertiary centres. Unilateral disease was determined using both AVS and postoperative outcome. Multivariable analysis was used to construct prediction models. We validated our tool in a European cohort of 97 patients enrolled in the SPARTACUS trial who underwent AVS. Previously published prediction models were also tested in our cohorts.

RESULTS

Backward stepwise logistic regression analysis yielded a final tool using baseline aldosterone-to-lowest-potassium ratio (APR, ng/dl/mmol/l), with an area under receiver-operating characteristic curve of 0.80 (95% CI 0.70-0.89). In the Asian development cohort, probability of bilateral disease was 90.0% (with APR <5) and probability of unilateral disease was 91.4% (with APR >15). Similar results were seen in the European validation cohort. Combining both cohorts, probability of bilateral disease was 76.7% (with APR <5), and probability for unilateral was 91.7% (with APR >15). Other models had similar predictive ability but required more variables, and were less sensitive for identifying bilateral PA.

CONCLUSION

The novel aldosterone-to-lowest-potassium ratio is a convenient score to guide clinicians and patients of various ethnicities on the probability of primary aldosteronism subtype. Using APR to identify patients more likely to benefit from AVS may be a cost-effective strategy to manage this common condition.

Determining the Prevalence of Primary Aldosteronism in Patients With New-Onset Type 2 Diabetes and Hypertension

CONTEXT

Despite a high prevalence of hypertension in diabetes and close relationship between primary aldosteronism (PA) and glucose metabolism, few study concerns the prevalence of PA in diabetes with hypertension.

OBJECTIVE

This study aimed to detect the prevalence of PA in patients with new-onset type 2 diabetes (T2D) and hypertension and to explore the association between PA and diabetes.

METHODS

A total of 256 outpatients with new-onset T2D and hypertension were screened for PA. Plasma aldosterone concentration (PAC), plasma renin activity (PRA) were measured. Patients with an aldosterone renin activity ratio (ARR) ≥ 30 ng/dL/ng/mL/h and PAC ≥ 15 ng/dL underwent confirmatory captopril challenge test (CCT) for PA. The diagnostic criteria for PA were, after CCT, (1) PAC decreased < 30%, (2) ARR maintained ≥ 30 ng/dL/ng/mL/h, and (3) PAC was ≥ 11 ng/dL.

RESULTS

Of 256 consecutive patients, 99 (39%) were positive for the screening test, and 49 (19%) were diagnosed with PA. Compared with those in groups A (screening test -) and B (screening test +, CCT -), patients in group C (diagnosed with PA) had a higher percentage of systolic blood pressure of ≥ 160 mmHg, less family history of hypertension, and lower serum potassium. Patients in group B and C had higher PAC and ARR levels, but lower PRA than those in group A. Homeostatic model assessment for insulin resistance (HOMA-IR) was positively associated with PAC level among the diabetic patients.

CONCLUSION

The prevalence of PA in new-onset T2D patients with hypertension is at least 19%. Higher aldosterone may be related with insulin resistance in patients with diabetes.

Bilateral Aldosterone Suppression in Patients With Right Unilateral Primary Aldosteronism and Review of the Literature

Introduction

Adrenal vein sampling (AVS) identifies unilateral primary aldosteronism but may occasionally show paradoxically low aldosterone–cortisol ratios bilaterally. Postulated reasons include venous anomalies, fluctuating aldosterone secretion, or superselective cannulation. We report our findings in patients who underwent repeat AVS and reviewed the current literature.

Methods

We performed a retrospective observational study of patients undergoing AVS in an experienced high-volume tertiary center over a 5-year period.

Results

From 2015 to 2019, 61 patients underwent sequential cosyntropin-stimulated AVS and all had bilateral successful cannulation (100%). Four of 61 (6.6%) patients had bilaterally low aldosterone–cortisol ratios. Three patients underwent repeat AVS, with all 3 cases demonstrating right-sided lateralization and cure of disease postadrenalectomy. Right-sided disease was also more common in other reports. This may be due to inadvertent superselective cannulation of the short right adrenal vein, resulting in sampling of the adjacent normal gland. Cortisol results cannot detect this problem. In 1 patient, computed tomography venography excluded any accessory right adrenal veins. In another patient, repeat bilateral simultaneous unstimulated AVS was done, and measurements of metanephrines aided in accurately identifying right-sided lateralization.

Conclusion

In addition to technical difficulties in cannulating the right adrenal vein, we also have to avoid performing superselective cannulation inadvertently. In cases of inconclusive AVS, repeat sampling may identify patients with potentially curable unilateral primary aldosteronism. The role of corticotropin stimulation and metanephrines measurements during repeat AVS requires further study.

Prevalence, diagnosis and outcomes of treatment for primary aldosteronism

Primary aldosteronism (PA) is the most common potentially curable form of hypertension. The overproduction of aldosterone leads to an increased risk of cardiovascular and cerebrovascular events as well as adverse effects to the heart and kidney and psychological disorders. PA is mainly caused by unilateral aldosterone excess due to an aldosterone-producing adenoma or bilateral excess due to bilateral adrenocortical hyperplasia. The diagnostic work-up of PA comprises three steps: screening, confirmatory testing and differentiation of unilateral surgically-correctable forms from medically treated bilateral PA. These specific treatments can mitigate or reverse the increased risks associated with PA. Herein we summarise the prevalence, outcomes and current and future clinical approaches for the diagnosis of primary aldosteronism.

Higher Screening Aldosterone to Renin Ratio in Primary Aldosteronism Patients with Diabetes Mellitus

Accumulated evidence has shown that low renin hypertension is common in patients with diabetic nephropathy. However, the performance of aldosterone to renin ratio (ARR) in primary aldosteronism (PA) patients with diabetes has not been well validated. Here, we report the performance of screening ARR in PA patients with diabetes. The study enrolled consecutive patients and they underwent ARR testing at screening. Then the diagnosis of PA was confirmed from the Taiwan Primary Aldosteronism Investigation registration dataset. Generalized additive model smoothing plot was used to validate the performance of screening ARR in PA patients with or without diabetes. During this study period, 844 PA patients were confirmed and 136 (16.0%) among them had diabetes. Other 816 patients were diagnosed with essential hypertension and used as the control group and 89 (10.9%) among them had diabetes. PA patients with diabetes were older and had a longer duration of hypertensive latency, higher systolic blood pressure and lower glomerular filtration rate than those PA patients without diabetes. The cut-off value of ARR in the generalized additive model predicting PA was 65 ng/dL per ng/mL/h in diabetic patients, while 45 ng/dL per ng/mL/h in non-diabetic patients. There was a considerable prevalence of diabetes among PA patients, which might be capable of interfering with the conventional screening test. The best cut-off value of ARR, more than 65 ng/dL per ng/mL/h in PA patients with diabetes, was higher than those without diabetes.

Primary aldosteronism in the primary care setting

PURPOSE OF REVIEW

The aim of the present manuscript is to provide an overview of the most updated studies on the prevalence of primary aldosteronism in primary care and to compare these figures with the actual rate of diagnosis in clinical practice and with the prevalence of primary aldosteronism in specific subgroup of patients.

RECENT FINDINGS

Over the last 20 years the clinical spectrum of low renin hypertension and primary aldosteronism has changed dramatically. Once considered only in the presence of severe hypertension and hypokalemia, it is now well known that primary aldosteronism is not uncommon even in patients with mild forms of hypertension and/or normokalemia. Moreover, recent evidence points toward a large proportion of normotensive study participants as being affected by subclinical primary aldosteronism, which represents a strong risk factor for incident hypertension. Moreover, primary aldosteronism patients are exposed to an increased risk of cardio and cerebrovascular events and metabolic comorbidities compared with patients affected by essential hypertension. Disappointingly, primary aldosteronism remains a largely underdiagnosed and undertreated disorder.

SUMMARY

These recent findings further highlight the importance of widening the spectrum of patients who should be screened for primary aldosteronism, to reduce the cardiovascular risk associated with this medical condition.

Prevalence of primary aldosteronism in primary care: a cross-sectional study

BACKGROUND

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension. Reported prevalences of PA vary considerably because of a large heterogeneity in study methodology.

AIM

To examine the proportion of patients with PA among patients with newly diagnosed, never treated hypertension.

DESIGN AND SETTING

A cross-sectional study set in primary care.

METHOD

GPs measured aldosterone and renin in adult patients with newly diagnosed, never treated hypertension. Patients with elevated aldosterone-to-renin ratio and increased plasma aldosterone concentration underwent a saline infusion test to confirm or exclude PA. The source population was meticulously assessed to detect possible selection bias.

RESULTS

Of 3748 patients with newly diagnosed hypertension, 343 patients were screened for PA. In nine out of 74 patients with an elevated aldosterone-to-renin ratio and increased plasma aldosterone concentration the diagnosis of PA was confirmed by a saline infusion test, resulting in a prevalence of 2.6% (95% confidence interval = 1.4 to 4.9). All patients with PA were normokalaemic and 8 out of 9 patients had sustained blood pressure >150/100 mmHg. Screened patients were younger (P<0.001) or showed higher blood pressure (P<0.001) than non-screened patients.

CONCLUSION

In this study a prevalence of PA of 2.6% in a primary care setting was established, which is lower than estimates reported from other primary care studies so far. This study supports the screening strategy as recommended by the Endocrine Society Clinical Practice Guideline. The low proportion of screened patients (9.2%), of the large cohort of eligible patients, reflects the difficulty of conducting prevalence studies in primary care clinical practice.

Prevalence of primary aldosteronism among patients with type 2 diabetes

CONTEXT

Diabetes and hypertension coexist in 40%-60% of individuals with type 2 diabetes. The coexistence of these two conditions is associated with increased risk of retinopathy, nephropathy and cardiovascular disease.

OBJECTIVE

To investigate the prevalence of primary aldosteronism (PA) in a general cohort of persons with type 2 diabetes.

DESIGN

Cross-sectional study involving six diabetes outpatient clinics in Sweden.

PATIENTS

were enrolled individuals with type 2 diabetes between February 2008 and December 2013.

MEASUREMENTS

Plasma aldosterone concentrations (PAC pmol/L) and direct renin concentrations (DRC mIU/L) were measured. Patients with increased aldosterone renin ratios (ARR) >65 were further evaluated for PA.

RESULTS

Of 578 consecutively screened patients with type 2 diabetes, 27 were treated with mineralocorticoid receptor antagonists (MRA) and potassium-sparing diuretics not further evaluated. Among the remaining 551 patients, 38 had increased ARR, including 22 who were clinically indicated for PA tests and 16 who were not further evaluated due to severe comorbidities and old age. There were five (0.93%) patients with confirmed PA after computerized tomography and adrenal venous sampling. Patients with PA had higher systolic blood pressure (P=.032) and lower potassium levels (P=.027) than those without PA. No significant association was found between plasma aldosterone and diabetic complications.

CONCLUSIONS

The prevalence of PA in an unselected cohort of patients with type 2 diabetes is relatively low, and measures of plasma aldosterone are not strong risk factors for micro- and macrovascular diabetic complications.

PREVELENCE OF PRIMARY ALDOSTERONISM IN AN URBAN HYPERTENSIVE POPULATION

OBJECTIVE

To determine the prevalence of primary aldosteronism (PA) in hypertensive patients presenting to the primary care clinic at The Mount Sinai Hospital, regardless of the degree of hypertension and to identify clinical criteria that should prompt screening for PA.

METHODS

An aldosterone:renin ratio (ARR, cutoff ≥20, with plasma aldosterone concentration [PAC] ≥10 and suppressed renin) was used to prospectively screen 296 hypertensive patients (blood pressure [BP] ≥140/90) over the age of 18 from August 2012 through May 2013. Subjects who screened positive then underwent confirmatory oral salt load testing (OSLT).

RESULTS

Of the 296 patients, 14 screened positive for PA, an overall prevalence of 4.7%. Six of the 14 cases underwent confirmatory OSLT, upon which 2 were confirmed positive, for a prevalence of 0.7%. Overall, patients with confirmed PA were more likely to have resistant hypertension (42.9% vs. 18.1% (P = .0334)) and require more antihypertensive agents (2.8 ± 1.2 agents vs. 2.1 ± 1.1 agents, P = .0213). There was a trend toward lower potassium values in the cases.

CONCLUSION

The prevalence of PA in our clinic is much lower than in reports from certain "at-risk" populations. PA screening is indicated in patients with resistant hypertension, regardless of serum potassium levels.

ABBREVIATIONS

ARR = aldosterone:renin ratio ACTH = adrenocorticotropic hormone AVS = adrenal venous sampling BP = blood pressure MRA = mineralocorticoid receptor antagonist OSLT = oral salt load confirmatory test PA = primary aldosteronism PAC = plasma aldosterone concentration PCP = primary care provider PRA = plasma renin activity.

Secondary hypertension in adults

Secondary hypertension occurs in a significant proportion of adult patients (~10%). In young patients, renal causes (glomerulonephritis) and coarctation of the aorta should be considered. In older patients, primary aldosteronism, obstructive sleep apnoea and renal artery stenosis are more prevalent than previously thought. Primary aldosteronism can be screened by taking morning aldosterone and renin levels, and should be considered in patients with severe, resistant or hypokalaemia-associated hypertension. Symptoms of obstructive sleep apnoea should be sought. Worsening of renal function after starting an angiotensin-converting enzyme inhibitor suggests the possibility of renal artery stenosis. Recognition, diagnosis and treatment of secondary causes of hypertension lead to good clinical outcomes and the possible reversal of end-organ damage, in addition to blood pressure control. As most patients with hypertension are managed at the primary care level, it is important for primary care physicians to recognise these conditions and refer patients appropriately.

Primary aldosteronism: challenges in diagnosis and management

Primary aldosteronism (PA) is the main cause of endocrine hypertension, present in approximately 10% of hypertensive patients; about one-third is secondary to aldosterone-producing adenomas. Cardiovascular and renal morbidity are out of proportion to the degree of hypertension. Physicians have compelling rationale to correctly identify and treat PA. Physicians are challenged with patient selection for screening with the aldosterone/renin ratio (ARR), interpretation of ARR, and selecting a confirmatory test. Adrenal vein sampling is performed for subtype differentiation. The treatment depends on the disease subtype and results in control of hypertension and reversal of associated excess morbidity.

The value of losartan suppression test in the confirmatory diagnosis of primary aldosteronism in patients over 50 years old

OBJECTIVE

The diagnosis of primary aldosteronism (PA) among the older-aged population has posed a crucial challenge. Among patients over 50 years old, this trial assessed comparability of the performance of two PA diagnostic tests: losartan and captopril suppression tests.

METHODS

A post-hoc subgroup analysis from a prospective cohort was conducted by the TAIPAI (Taiwan Primary Aldosteronism Investigation) group between July 2003 and July 2006. Of the 160 patients in the cohort, 60 patients over 50 years old received captopril and losartan tests to confirm PA.

RESULTS

Among the 60 patients over 50 years old, 31 patients had PA confirmed by standardized protocol. The area under the receiver-operating characteristic (ROC) curve for post-captopril aldosterone was significantly less than that for post-losartan plasma aldosterone concentration (PAC) (0.87 vs 0.94, p=0.02). Using the aldosterone-renin ratio (ARR)>35 with PAC>10 ng/dl, the specificity was 82.76% vs 93.1% and the sensitivity was 77.42% vs 87.10% for the captopril and losartan tests, respectively. The equivalence between the two tests were confirmed by the exact McNemar's test (p=1.0).

CONCLUSION

The losartan test showed comparable accuracy to confirm PA. Verification of this "elderly-friendly" confirmatory test will be the first step to prepare a specific diagnostic model of PA for the older-aged population.

Primary aldosteronism: emerging trends

Primary aldosteronism (PA) is the most common etiology of endocrine hypertension (HTN), and recent prevalence studies suggest that it may be under-diagnosed. Indications for screening have been expanded with recognition that many patients with PA do not have hypokalemia and that the disease may be familial. The aldosterone:renin ratio (ARR) is the preferred screening test for PA. The ARR can be interpreted in patients on most anti-hypertensive agents, and can be used to guide medical therapy of HTN even in patients without PA. Once PA is confirmed, adrenal venous sampling (AVS) should be performed to determine if PA is due to bilateral disease or a unilateral adenoma, if surgery is being considered. Targeted medical or surgical therapy improves patient outcomes.

Prevalence and clinical characteristics of primary aldosteronism in Japanese patients with type 2 diabetes mellitus and hypertension

The prevalence of primary aldosteronism (PA) is around 3-15% in patients with hypertension. Hypertension is a frequent complication of type 2 diabetes mellitus (DM) because of the close etiological relationship between these two diseases. However, the possibility of PA in patients with DM and hypertension is often overlooked and the prevalence of PA in patients with DM and hypertension in Japan is unknown. We enrolled 124 hospitalized patients with both DM and hypertension. PA was diagnosed according to the modified criteria for Japanese patients. We examined the prevalence of PA and compared clinical characteristics between patients with and without PA. In another analysis of 43 patients with a confirmed diagnosis of PA, we compared the characteristics of patients with and without DM. Overall, 14/124 patients with DM and hypertension (11.3%) were diagnosed with PA. Multivariate logistic regression showed that the duration of DM was significantly shorter in the PA group. Fisher's direct probability test revealed that history of hypertension before the diagnosis of DM was a significant factor in patients with PA. Treatment with an angiotensin II receptor blocker (ARB) did not affect the diagnosis of PA in these patients. Among 43 patients with PA, those with DM were significantly older and the delay to the diagnosis of PA was significantly longer compared with patients without DM. In conclusion, almost 10% of patients with DM and hypertension actually have PA. More extensive screening for PA is recommended in patients with DM and hypertension, regardless of the use of ARBs.

Prevalence of primary aldosteronism in hypertensive subjects with hyperglycemia

The aim of this study was to examine the prevalence of primary aldosteronism (PA) in hypertensive patients with hyperglycemia. Two hundred and thirty-two hypertensive patients with hyperglycemia were screened for PA. Fifty-four subjects with an aldosterone/rennin activity ratio >20 ng/dL per ng/mL/hour underwent a saline loading test. Primary aldosteronism was present in 22.4% of patients with a plasma aldosterone concentration >5 ng/dL and 11.6% of those with plasma aldosterone concentrations >10 ng/dL. There were 14.0%-23.0% patients with PA in the diabetes mellitus group, 2.3%-23.3% in the impaired glucose tolerance group, and 9.1% in the impaired fasting glucose group. Primary aldosteronism is common in hypertensive individuals with hyperglycemia.

Changes in the perceived epidemiology of primary hyperaldosteronism

Primary aldosteronism has been considered a rare disease in the past years, affecting 1% of the hypertensive population. Subsequently, growing evidence of its higher prevalence is present in literature, although the estimates of disease range from 5 up to 20%, as in type 2 diabetes and resistant hypertension. The main reasons for these variations are associated with the selection of patients and diagnostic procedures. If we consider that hypertension is present in about 20% of the adult population, primary aldosteronism can no longer be considered a rare disease. Patients with primary aldosteronism have a high incidence of cardiovascular, cerebrovascular and kidney complications. The identification of these patients has therefore a practical value on therapy, and to control morbidities derived from vascular damage. The ability to identify the prevalence of a disease depends on the number of subjects studied and the methods of investigation. Epidemiological studies are affected by these two problems: there is not consensus on patients who need to be investigated, although testing is recommended in subjects with resistant hypertension and diabetes. The question of how to determine aldosterone and renin levels is open, particularly if pharmacological wash-out is difficult to perform because of inadequate blood pressure control.