Unawareness of Primary Aldosteronism as a Common Cause of Hypokalemia - Insights from the IPAHK+ Trial (Incidence of Primary Aldosteronism in Patients with Hypokalemia)

Hypokalemia plays an important role in the diagnosis and management of primary aldosteronism (PA). While the hypokalemic variant of the disease accounts for about one third of all cases, little is known about the incidence of PA in hypokalemic populations. The IPAHK+ study is an epidemiological, cross-sectional trial to provide evidence on the incidence of PA in hypokalemic patients from a university hospital outpatient population. Recruitment of outpatients with hypokalemia≤3 mmol/l is carried out on a continuous referral-basis through an automated data delivery system. Up to an interim data closure, 66 patients underwent the study protocol. The mean age of the participants was 52.9±1.5 years with an equal sex ratio of 1:1 women to men, a mean potassium value of 2.78±0.31 mmol/l [1.8;3.0] and a prevalence of arterial hypertension of 72.7%. PA was diagnosed in 46.6% of all participants, all of whom had a history of hypertension. Incidence of PA increased continuously with decreasing potassium levels with proportions of 26.7%, 50% and 57.1% in the subgroups of 3.0 mmol/l (n=15), 2.8-2.9 mmol/l (n=22) and≤2.7 mmol/l (n=21), respectively. Prior to testing, 59.1% of all patients presented at least with one plausible other cause of hypokalemia. The incidence of PA in the investigated outpatient population was more than 4 out of 10 and inversely correlated with baseline potassium levels. Moderate or severe hypokalemia, regardless of its cause, should therefore prompt evaluation for PA in hypertensive individuals. Normotensive hypokalemic PA was not observed in this cohort.

Sleep disturbances in primary aldosteronism are associated to depressive symptoms - Could specific mineralocorticoidreceptors be a common pathway?

Symptoms of depression and anxiety are frequent in patients with primary aldosteronism (PA) and are supposed to be independent risk factors for cardiovascular diseases (CVD). As patients with PA have an increased cardiovascular risk compared to patients with essential hypertension, sleep disturbances, which often accompany depressive and anxiety symptoms, may be an additional contributor to the cardiometabolic consequences of PA. To clarify this possible link we investigated 132 patients with PA at baseline and after one year after initiation of treatment either by adrenalectomy (ADX) or mineralocorticoid-receptor-antagonist (MRA). Sleep disturbances and daytime sleepiness were assessed with Pittsburg sleep Inventory (PSQI) and Epworth sleepiness scale (ESS). Patients with PA showed pathological scores for sleep disturbances at baseline according to PSQI, with females being more affected (8.1 vs. 5.7 p < 0.001), which was significantly improved after initiation of specific treatment (p = 0.002). For ESS we found scores within the normal range, but higher than the general population, which significantly improved at follow-up (p < 0.001). The intensity of sleep disturbances was highly correlated with scores of anxiety and depression at baseline and follow-up. However, clinical and biochemical markers of PA (e.g. aldosterone, blood pressure) and metabolic markers did not show a consistent association with sleep changes. The degree of improvement in PSQI was significantly associated with the improvement of brief patients health questionnaire (PHQD) (p = 0.0151). Sleep disturbances seem not to be an independent risk factor for cardiovascular and metabolic problems in PA. They are strongly associated to depressive symptoms and maybe mediated by the same mineralocorticoid receptor circuits.

Prevalence of primary aldosteronism in acute stroke or transient ischemic attack: a systematic review and meta-analysis

Background and purpose

Primary aldosteronism (PA) is the most common endocrine cause of secondary hypertension with a prevalence of 14% in patients with newly diagnosed hypertension. Patients with PA experience a higher rate of cardiovascular events including stroke when compared to those with blood pressure matched essential hypertension. This systematic review and meta-analysis summarize current evidence on the prevalence of PA in patients with acute stroke or transient ischemic attack (TIA).

Methods

Two reviewers independently reviewed the literature for observational studies on the prevalence of PA in patients with acute stroke or TIA. MEDLINE and Embase were searched for studies up to December 13, 2023.

Results

Three single center studies conducted in Japan, Singapore and China were found to meet the inclusion criteria. The reported prevalence of PA in two cohort studies of adults with stroke or TIA were 3.1% and 4.0% and a third cross-sectional study in adults under 45 years old revealed a prevalence rate of 12.9%. Following a meta-analysis, the pooled prevalence of PA in adults with stroke or TIA is 5.8% [95% CI 1.6%-12.3%].

Conclusions

A considerable proportion of patients with stroke or TIA may have PA as the underlying cause of their hypertension. Given the increased risk of stroke associated with PA, clinicians should consider screening for PA in hypertensive patients with stroke or TIA. Further research is needed to evaluate the effect of timing and interfering medications on test results, which will inform an evidence-based approach to testing for PA following TIA or stroke.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022328644.

Differences in the clinical and hormonal presentation of patients with familial and sporadic primary aldosteronism

Purpose

To compare the clinical and hormonal characteristics of patients with familial hyperaldosteronism (FH) and sporadic primary aldosteronism (PA).

Methods

A systematic review of the literature was performed for the identification of FH patients. The SPAIN-ALDO registry cohort of patients with no suspicion of FH was chosen as the comparator group (sporadic group).

Results

A total of 360 FH (246 FH type I, 73 type II, 29 type III, and 12 type IV) cases and 830 sporadic PA patients were included. Patients with FH-I were younger than sporadic cases, and women were more commonly affected (P = 0.003). In addition, the plasma aldosterone concentration (PAC) was lower, plasma renin activity (PRA) higher, and hypokalemia (P < 0.001) less frequent than in sporadic cases. Except for a younger age (P < 0.001) and higher diastolic blood pressure (P = 0.006), the clinical and hormonal profiles of FH-II and sporadic cases were similar. FH-III had a distinct phenotype, with higher PAC and higher frequency of hypokalemia (P < 0.001), and presented 45 years before sporadic cases. Nevertheless, the clinical and hormonal phenotypes of FH-IV and sporadic cases were similar, with the former being younger and having lower serum potassium levels.

Conclusion

In addition to being younger and having a family history of PA, FH-I and III share other typical characteristics. In this regard, FH-I is characterized by a low prevalence of hypokalemia and FH-III by a severe aldosterone excess causing hypokalemia in more than 85% of patients. The clinical and hormonal phenotype of type II and IV is similar to the sporadic cases.

Epidemiology and diagnosis of primary aldosteronism. What have we learned from the SPAIN-ALDO registry?

PURPOSE

To summarize the available data on the prevalence, clinical repercussion, and diagnosis of primary aldosteronism (PA) and to discuss the SPAIN-ALDO registry's findings, which is the largest PA patient registry in Spain.

METHODS

A comprehensive review of the literature focused on the prevalence, clinical presentation and diagnosis of PA was performed.

RESULTS

PA is the most common cause of secondary arterial hypertension. In addition, PA patients have a higher cardio-metabolic risk than patients with essential arterial hypertension matched by age, sex, and blood pressure levels. However, despite its high prevalence and associated metabolic and cardiovascular complications, PA remains largely under-recognized, with less than 2% of people in at-risk populations ever tested. The diagnostic investigation is a multistep process, including screening, confirmatory testing, and subtype differentiation of unilateral from bilateral PA forms. Data from the SPAIN-ALDO registry have shed light on the cardiometabolic impact of PA and about the limitations in the PA diagnosis of these patients in Spain.

CONCLUSIONS

The most common cause of secondary hypertension is PA. One of the most challenging aspects of the diagnosis is the differentiation between unilateral and bilateral PA because adrenal venous sampling is a difficult procedure that should be performed in experienced centers. Data from the SPAIN-ALDO registry have provided important information on the nationwide management of this pathology.

Follow-up care and assessment of comorbidities and complications in patients with primary aldosteronism: The clinical practice guideline of the Taiwan Society of aldosteronism

Primary aldosteronism (PA) is the most common form of endocrine hypertension, characterized by excess aldosterone production that leads to an increased risk of cardiovascular events and target organ damage. Both adrenalectomy and medical treatment have shown efficacy in improving clinical outcomes and comorbidities associated with PA, including a specific subtype of PA with autonomous cortisol secretion (ACS). Understanding the comorbidities of PA and establishing appropriate follow-up protocols after treatment are crucial for physicians to enhance morbidity and mortality outcomes in patients with PA. Additionally, the screening for hypercortisolism prior to surgery is essential, as the prognosis of patients with coexisting PA and ACS differs from those with PA alone. In this review, we comprehensively summarize the comorbidities of PA, encompassing cardiovascular, renal, and metabolic complications. We also discuss various post-treatment outcomes and provide insights into the strategy for glucocorticoid replacement in patients with overt or subclinical hypercortisolism. This clinical practice guideline aims to equip medical professionals with up-to-date information on managing concurrent hypercortisolism, assessing treatment outcomes, and addressing comorbidities in patients with PA, thereby improving follow-up care.

Primary aldosteronism and obstructive sleep apnea: A meta-analysis of prevalence and metabolic characteristics

BACKGROUND

Primary aldosteronism (PA) and obstructive sleep apnea (OSA) are both causes for resistant hypertension and contribute to adverse cardiovascular outcome. However, the association of these two disorders remains to be investigated. We conducted this meta-analysis to estimate the prevalence and metabolic characteristics of the coexistence of PA and OSA.

METHODS

The databases of MEDLINE, EMBASE and Cochrane Reviews were searched for studies investigating the prevalence or clinical characteristics of PA and OSA until Jan 2023. Single proportions of PA and OSA were meta-analyzed for pooled prevalence and 95% confidence intervals (CIs). Odds ratios (ORs) and 95% CIs were calculated for the comparison of the prevalence. Mean differences (MDs) and 95% CIs were calculated for comparisons of the characteristics between patients with both OSA and PA and control groups.

RESULTS

A total of 16 studies were included. The pooled prevalence of PA was 27% (95% CI = 24-29%) in all patients with OSA (n = 3498). The prevalence of PA in patients with OSA was significantly higher than that in the patients without OSA (OR = 2.03, 95% CI = 1.30, 3.16, p = 0.002). The pooled prevalence (95% CI) of OSA was 46% (39-54%) in patients with PA (n = 2335). Compared with the hypertensive patients without PA, the prevalence of OSA in the patients with PA was significantly higher (OR = 2.01, 95% CI = 1.37, 2.95, p < 0.001). Compared with the patients of control groups, the patients with both PA and OSA had higher blood pressure and body mass index (BMI).

CONCLUSION

Screening for the coexistence of PA and OSA was warranted.

What We Know about and What Is New in Primary Aldosteronism

Primary aldosteronism (PA), a significant and curable cause of secondary hypertension, is seen in 5-10% of hypertensive patients, with its prevalence contingent upon the severity of the hypertension. The principal aetiologies of PA include bilateral idiopathic hypertrophy (BIH) and aldosterone-producing adenomas (APAs), while the less frequent causes include unilateral hyperplasia, familial hyperaldosteronism (FH) types I-IV, aldosterone-producing carcinoma, and ectopic aldosterone synthesis. This condition, characterised by excessive aldosterone secretion, leads to augmented sodium and water reabsorption alongside potassium loss, culminating in distinct clinical hallmarks: elevated aldosterone levels, suppressed renin levels, and hypertension. Notably, hypokalaemia is present in only 28% of patients with PA and is not a primary indicator. The association of PA with an escalated cardiovascular risk profile, independent of blood pressure levels, is notable. Patients with PA exhibit a heightened incidence of cardiovascular events compared to counterparts with essential hypertension, matched for age, sex, and blood pressure levels. Despite its prevalence, PA remains frequently undiagnosed, underscoring the imperative for enhanced screening protocols. The diagnostic process for PA entails a tripartite assessment: the aldosterone/renin ratio (ARR) as the initial screening tool, followed by confirmatory and subtyping tests. A positive ARR necessitates confirmatory testing to rule out false positives. Subtyping, achieved through computed tomography and adrenal vein sampling, aims to distinguish between unilateral and bilateral PA forms, guiding targeted therapeutic strategies. New radionuclide imaging may facilitate and accelerate such subtyping and localisation. For unilateral adrenal adenoma or hyperplasia, surgical intervention is optimal, whereas bilateral idiopathic hyperplasia warrants treatment with mineralocorticoid antagonists (MRAs). This review amalgamates established and emerging insights into the management of primary aldosteronism.

Subclinical Primary Aldosteronism and Cardiovascular Health: A Population-Based Cohort Study

BACKGROUND

Primary aldosteronism, characterized by overt renin-independent aldosterone production, is a common but underrecognized form of hypertension and cardiovascular disease. Growing evidence suggests that milder and subclinical forms of primary aldosteronism are highly prevalent, yet their contribution to cardiovascular disease is not well characterized.

METHODS

This prospective study included 1284 participants between the ages of 40 and 69 years from the randomly sampled population-based CARTaGENE cohort (Québec, Canada). Regression models were used to analyze associations of aldosterone, renin, and the aldosterone-to-renin ratio with the following measures of cardiovascular health: arterial stiffness, assessed by central blood pressure (BP) and pulse wave velocity; adverse cardiac remodeling, captured by cardiac magnetic resonance imaging, including indexed maximum left atrial volume, left ventricular mass index, left ventricular remodeling index, and left ventricular hypertrophy; and incident hypertension.

RESULTS

The mean (SD) age of participants was 54 (8) years and 51% were men. The mean (SD) systolic and diastolic BP were 123 (15) and 72 (10) mm Hg, respectively. At baseline, 736 participants (57%) had normal BP and 548 (43%) had hypertension. Higher aldosterone-to-renin ratio, indicative of renin-independent aldosteronism (ie, subclinical primary aldosteronism), was associated with increased arterial stiffness, including increased central BP and pulse wave velocity, along with adverse cardiac remodeling, including increased indexed maximum left atrial volume, left ventricular mass index, and left ventricular remodeling index (all P<0.05). Higher aldosterone-to-renin ratio was also associated with higher odds of left ventricular hypertrophy (odds ratio, 1.32 [95% CI, 1.002-1.73]) and higher odds of developing incident hypertension (odds ratio, 1.29 [95% CI, 1.03-1.62]). All the associations were consistent when assessing participants with normal BP in isolation and were independent of brachial BP.

CONCLUSIONS

Independent of brachial BP, a biochemical phenotype of subclinical primary aldosteronism is negatively associated with cardiovascular health, including greater arterial stiffness, adverse cardiac remodeling, and incident hypertension.

Renin as a Biomarker to Guide Medical Treatment in Primary Aldosteronism Patients. Findings from the SPAIN-ALDO Registry

INTRODUCTION

Primary aldosteronism (PA) is associated with several cardiometabolic comorbidities. Specific treatment by mineralocorticoid receptor antagonists (MRA) or adrenalectomy has been reported to reduce the cardiometabolic risk. However, the cardiovascular benefit could depend on plasma renin levels in patients on MRA.

AIM

To compare the development of cardiovascular, renal and metabolic complications between medically treated patients with PA and those who underwent adrenalectomy, taking the renin status during MRA treatment into account.

METHODS

A multicenter retrospective study (SPAIN-ALDO Register) of patients with PA treated at 35 Spanish tertiary hospitals. Patients on MRA were divided into two groups based on renin suppression (n = 90) or non-suppression (n = 70). Both groups were also compared to unilateral PA patients (n = 275) who achieved biochemical cure with adrenalectomy.

RESULTS

Adrenalectomized patients were younger, had higher plasma aldosterone concentration, and lower potassium levels than MRA group. Patients on MRA had similar baseline characteristics when stratified into treatment groups with suppressed and unsuppressed renin. 97 (55.1%) of 176 patients without comorbidities at diagnosis, developed at least one comorbidity during follow-up (median 12 months vs. 12.5 months' follow-up after starting MRA and surgery, respectively). Surgery group had a lower risk of developing new cardiovascular events (HR 0.40 [95% CI 0.18-0.90]) than MRA group. Surgical treatment improved glycemic and blood pressure control, increased serum potassium levels, and required fewer antihypertensive drugs than medical treatment. However, there were no differences in the cardiometabolic profile or the incidence of new comorbidities between the groups with suppressed and unsuppressed renin levels (HR 0.95 [95% CI 0.52-1.73]).

CONCLUSION

Cardiovascular, renal, and metabolic events were comparable in MRA patients with unsuppressed and suppressed renin. Effective surgical treatment of PA was associated with a decreased incidence of new cardiovascular events when compared to MRA therapy.

Development of a risk-prediction model for primary aldosteronism in veterans with hypertension

BACKGROUND

Rates of screening for primary aldosteronism in patients who meet the criteria are exceedingly low (1%-3%). To help clinicians prioritize screening in patients most likely to benefit, we developed a risk-prediction model.

METHODS

Using national Veterans Health Administration data, we identified patients who met the criteria for primary aldosteronism screening between 2000 and 2019. We performed multivariable logistic regression to identify characteristics associated with positive primary aldosteronism testing before generating a risk-scoring system based on the coefficients (0< β < 0.5 = 1 pt, 0.5 ≤ β < 1 = 2 pts, 1 ≤ β < 1.5 = 3 pts) and then tested the system performance using an internal validation cohort.

RESULTS

We identified 502,190 patients who met primary aldosteronism screening criteria, of whom 1.6% were screened and 15% tested positive. Based on the regression model, we generated a risk-scoring system based on a total of 9 possible points in which age under 50, absence of smoking history, and resistant hypertension each scored 1 point; elevated serum sodium 2 points; and hypokalemia 3 points. Rates of positive screening increased with risk score, with 5.6% to 6.7% of those scoring 0 points testing positive; 7.9% to 9.0% 1 point; 8.6% to 10% 2 points; 13% to 14% 3 points; 21% 4 points; 22% to 38% 5 points; 27% to 38% 6 points; 42% to 49% 7 points; and 50% to 51% ≥8 points.

CONCLUSION

In hypertensive patients who meet the criteria for primary aldosteronism screening, rates of positive screening range from 5.6% to 51%. Use of our risk-predication model incorporating these factors can identify patients most likely to benefit from testing.

Effect of Obesity on Clinical Characteristics of Primary Aldosteronism Patients at Diagnosis and Postsurgical Response

CONTEXT

Patients with obesity have an overactivated renin-angiotensin-aldosterone system (RAAS) that is associated with essential hypertension. However, the influence of obesity in primary aldosteronism (PA) is unknown.

OBJECTIVE

We analyzed the effect of obesity on the characteristics of PA, and the association between obesity and RAAS components.

METHODS

A retrospective study was conducted of the Spanish PA Registry (SPAIN-ALDO Registry), which included patients with PA seen at 20 tertiary centers between 2018 and 2022. Differences between patients with and without obesity were analyzed.

RESULTS

A total of 415 patients were included; 189 (45.5%) with obesity. Median age was 55 years (range, 47.3-65.2 years) and 240 (58.4%) were male. Compared to those without obesity, patients with obesity had higher rates of diabetes mellitus, chronic kidney disease, obstructive apnea syndrome, left ventricular hypertrophy, prior cardiovascular events, higher means of systolic blood pressure, and required more antihypertensive drugs. Patients with PA and obesity also had higher values of serum glucose, glycated hemoglobin A1c, creatinine, uric acid, and triglycerides, and lower levels of high-density lipoprotein cholesterol. Levels of blood aldosterone (PAC) and renin were similar between patients with and without obesity. Body mass index was not correlated with PAC nor renin. The rates of adrenal lesions on imaging studies, as well as the rates of unilateral disease assessed by adrenal vein sampling or I-6β-iodomethyl-19-norcholesterol scintigraphy, were similar between groups.

CONCLUSION

Obesity in PA patients involves a worse cardiometabolic profile, and need for more antihypertensive drugs but similar PAC and renin levels, and rates of adrenal lesions and lateral disease than patients without obesity. However, obesity implicates a lower rate of hypertension cure after adrenalectomy.

Primary aldosteronism and lower-extremity arterial disease: a two-sample Mendelian randomization study

BACKGROUND AND AIMS

Primary aldosteronism (PA) is an adrenal disorder of autonomous aldosterone secretion which promotes arterial injury. We aimed to explore whether PA is causally associated with lower-extremity arterial disease (LEAD).

METHODS

We included 39,713 patients with diabetes and 419,312 participants without diabetes from UK Biobank. We derived a polygenic risk score (PRS) for PA based on previous genome-wide association studies (GWAS). Outcomes included LEAD and LEAD related gangrene or amputation. We conducted a two-sample Mendelian randomization analysis for PA and outcomes to explore their potential causal relationship.

RESULTS

In whole population, individuals with a higher PA PRS had an increased risk of LEAD. Among patients with diabetes, compared to the subjects in the first tertile of PA PRS, subjects in the third tertile showed a 1.24-fold higher risk of LEAD (OR 1.24, 95% CI 1.03-1.49) and a 2.09-fold higher risk of gangrene (OR 2.09, 95% CI 1.27-3.44), and 1.72-fold higher risk of amputation (OR 1.72, 95% CI 1.10-2.67). Among subjects without diabetes, there was no significant association between PA PRS and LEAD, gangrene or amputation. Two-sample Mendelian randomization analysis indicated that genetically predictors of PA was significantly associated with higher risks of LEAD and gangrene (inverse variance weighted OR 1.20 [95% CI 1.08-1.34]) for LEAD, 1.48 [95% CI 1.28-1.70] for gangrene), with no evidence of significant heterogeneity or directional pleiotropy.

CONCLUSIONS

Primary aldosteronism is genetically and causally associated with higher risks of LEAD and gangrene, especially among patients with diabetes. Targeting on the autonomous aldosterone secretion may prevent LEAD progression.

Assessing the cardiovascular events and clinical outcomes of COVID-19 on patients with primary aldosteronism

BACKGROUND

Primary Aldosteronism (PA) is a common subtype of hypertension that increases the risk of adverse cardiovascular and kidney events. The impact of COVID-19 on patients with PA is not well understood. This study aimed to investigate the impact of COVID-19 on patients with PA and compare their outcomes with hypertensive patients with essential hypertension.

METHODS

A cohort study was conducted using data from the Trinetx platform, including 9,817,307 participants enrolled between January 1, 2020, and July 31, 2022. The study group consisted of participants who tested positive for PCR SARS-CoV-2. The primary outcome was critical care and all-cause mortality, while the secondary outcomes were major adverse cardiac events (MACE) or major adverse kidney events (MAKE). The study included 4814 patients with PA and 4814 hypertensive controls.

RESULTS

Patients with PA had a higher risk of critical outcomes than the hypertensive control group (adjusted hazard ratio [aHR] 1.14, p = 0.001). Moreover, they had higher risks of MACE (aHR 1.32, p < 0.001) and MAKE (aHR 1.36, p < 0.001) for up to 180 days after COVID-19. The analysis of the aHR as a horizon plot after discharge showed that patients with pre-existing PA and COVID-19 had the highest risk of critical outcomes at 7 months (aHR = 1.21), MACE (aHR = 1.35) at 9 months, and MAKE (aHR = 1.47) at 10 months compared to those with EH.

CONCLUSIONS

This study provides a comprehensive analysis of the cardiovascular impact of the COVID-19 pandemic on individuals with PA. The findings underscore the increased risk of mortality, critical care, MACE, and MAKE among patients with PA and COVID-19. The study highlights the need for continued optimization of strategies for follow-up care for patients with PA after SARS-CoV-2 infections.

The prevalence of primary and secondary hyperparathyroidism and its cardiometabolic implications in primary aldosteronism

BACKGROUND

The aim of this study was to analyze the prevalence of primary and secondary hyperparathyroidism in patients with primary aldosteronism (PA), and its implication on cardiovascular and metabolic outcomes.

METHODS

A retrospective study of patients with PA (exposed cohort, N.=44) and all hypertensive (EH) patients with adrenal lesions without PA nor other adrenal hypersecretion (non-exposed cohort, N.=41) on follow-up at our center between 2016 and 2020.

RESULTS

The mean age of patients with PA and EH was 55.1±14.13 and 66.3±10.93 (P<0.001), and 50% of PA and 39.0% of EH were women (P=0.309). At diagnosis, the prevalence of primary hyperparathyroidism in PA was of 18.2%, and all were normocalcemic hyperparathyroidism cases. Globally, no differences were found in the prevalence of primary hyperparathyroidism compared to EH (18.2% vs. 29.3%, P=0.229), but hypercalcemic primary hyperparathyroidism was significantly more prevalent in EH patients than in PA (22.0% vs. 0%, P=0.001). There were 47.7% (N.=21) cases of secondary hyperparathyroidism in patients with PA (4 due to chronic kidney disease (CKD) and vitamin D deficiency, and 17 due to vitamin D deficiency alone). The cardiometabolic profile of patients with PA and hyperparathyroidism (N.=29) was similar to of those patients without hyperparathyroidism (N.=15) at diagnosis and after a median follow-up of 3.6 years (interquartile range 1.1-5.9).

CONCLUSIONS

Although primary and secondary hyperparathyroidism are common in patients with PA, their prevalence was similar than the observed in EH patients. Primary hyperparathyroidism is usually mild in PA, appearing as normocalcemic forms. No negative implications of the hyperparathyroidism in the cardiometabolic profile of PA were observed.

Mortality in Patients With Primary Aldosteronism: A Swedish Nationwide Study

BACKGROUND

Primary aldosteronism (PA) is associated with increased mortality. The extent to which this phenomenon is affected by sex, age, comorbidities at diagnosis, and different treatment modalities is largely unknown. The objective was to determine all-cause and cause-specific mortality in a population-based cohort of patients with PA and the impact of age at diagnosis, sex, comorbidities, and treatment modalities.

METHODS

We used national registers to identify patients diagnosed with PA between 1997 and 2019 (n=2419) and controls (n=24 187) from the general population, matched for sex, age, and county of residence. We obtained mortality data from the Cause-of-Death Register. We used Cox regression models, adjusted for socioeconomic factors and diabetes, to estimate adjusted hazard ratios (HRs [95% CI]).

RESULTS

Overall, 346 (14.3%) patients with PA and 2736 (11.3%) controls died during a median follow-up time of 8.1 years. PA was associated with increased risk from all-cause mortality (HR, 1.23 [95% CI, 1.10-1.38]), death from cardiovascular disease (HR, 1.57 [95% CI, 1.30-1.89]), and stroke (HR, 1.85 [95% CI, 1.16-2.93]). Patients with cardiovascular disease at diagnosis (HR, 1.53 [1.26-1.85]), age >56 years (HR, 1.28 [95% CI, 1.13-1.45]), patients treated with a low dose of a mineralocorticoid receptor antagonist (HR, 1.30 [95% CI, 1.02-1.66]), and untreated patients (HR, 2.51 [95% CI, 1.72-3.67]) had excess mortality.

CONCLUSIONS

Mortality, mainly due to cardiovascular disease, is increased in patients with PA compared with controls from the general population, particularly in patients aged >56 years, patients with preexisting cardiovascular comorbidities, and patients receiving low dose of a mineralocorticoid receptor antagonist.

Sex modifies the predictive value of computed tomography combined with serum potassium for primary aldosteronism subtype diagnosis

Objective

We aimed to investigate the predictive value of the CT findings combined with serum potassium levels for primary aldosteronism (PA) subtype diagnosis, with a particular interest in sex differences.

Methods

In this retrospective study, we eventually included 482 PA patients who underwent successful adrenal venous sampling (AVS) and had available data. We diagnosed the subjects as having either unilateral (n = 289) or bilateral PA (n = 193) based on AVS. We analyzed the concordance rate between AVS and adrenal CT combined with serum potassium and performed a logistic regression analysis to assess the prevalence of unilateral PA on AVS.

Results

The total diagnostic concordance rate between CT findings and AVS was 51.5% (248/482). The prevalence of hypokalemia in men and women was 47.96% (129/269) and 40.85% (87/213), respectively. The occurrence of unilateral lesions on CT and hypokalemia was significantly associated with an increased prevalence of unilateral PA [odds ratio (OR) 1.537; 95% confidence interval (CI) 1.364-1.731; p < 0.001]. In male participants, G2 (bilateral lesion on CT and normokalemia), G3 (unilateral lesion on CT and normokalemia), G4 (bilateral normal on CT and hypokalemia), G5 (bilateral lesion on CT and hypokalemia), and G6 (unilateral lesion on CT and hypokalemia) were significantly increased for the prevalence of unilateral PA on AVS (G2: OR 4.620, 95% CI 1.408-15.153; G3: OR 6.275, 95% CI 2.490-15.814; G4: OR 3.793, 95% CI 1.191-12.082; G5: OR 16.476, 95% CI 4.531-59.905; G6: OR 20.101, 95% CI 7.481-54.009; all p < 0.05), compared with G1 (patients with bilateral normal on CT and normokalemia). However, among female participants, we found an increased likelihood for unilateral PA in patients with unilateral lesions on CT and hypokalemia alone (OR 10.266, 95% CI 3.602-29.259, p < 0.001), while no associations were found in other groups (all p > 0.05). Sex had a significant effect on modifying the relationship between unilateral PA and the combination of CT findings and serum potassium (p for interaction <0.001).

Conclusion

In conclusion, our results indicated that CT findings combined with serum potassium levels have a great value for predicting the subtype of PA and are stronger in men.

Increasing rates of referrals for investigation of primary aldosteronism at a tertiary centre

AIM

To describe the frequency and characteristics of patients referred for specialist investigation of primary aldosteronism (PA) in the lower North Island over a 5-year period, and the outcomes of those who received treatment.

METHODS

Patients who underwent confirmatory testing or treatment for PA at Wellington Regional Hospital were retrospectively identified and data were collected from electronic clinical records.

RESULTS

There has been a five-fold increase in both referrals and confirmatory testing for PA in 2021 compared to 2015. Compared to patients without PA, those eventually diagnosed with PA had a higher ARR, serum sodium, antihypertensive requirement and cardiovascular disease prevalence, as well as lower serum renin, potassium and GFR (all p <0.05), but similar blood pressure. Complete or partial clinical success was achieved in 96% of surgically treated patients compared with 70% of medically treated patients. Thirty-nine percent of patients experienced minor adverse effects with spironolactone and only one significant adverse event was experienced perioperatively.

CONCLUSIONS

The rate of referrals and confirmatory testing for PA are increasing in our region. Adrenalectomy and mineralocorticoid antagonist therapy are both safe and effective treatments, although minor adverse effects were common with spironolactone.

Primary aldosteronism: an unsuspected culprit of hypertension in systemic lupus erythematosus?

Primary aldosteronism (PA) is the most common endocrine cause of secondary hypertension and is associated with a high risk of cardiovascular disease in the general population. Patients suffering from systemic lupus erythematosus (SLE), a multisystem and multifactorial autoimmune disease, experience a high burden of hypertension and cardiovascular disease. Importantly, cardiovascular disease is one of the leading causes of death in SLE. Very limited evidence suggests an increased proportion of autoimmune diseases such as SLE in patients with PA. However, studies evaluating the prevalence of PA in the SLE population are lacking. Despite the potential for curative or targeted treatments, guidelines for the management of hypertension in SLE do not currently recommend testing for PA. This review highlights PA as a potentially over-looked secondary cause of hypertension in SLE, and offers future directions in research to improve the detection of this highly modifiable cardiovascular risk factor in the SLE population.

Prevalence, risk factors and evolution of diabetes mellitus after treatment in primary aldosteronism. Results from the SPAIN-ALDO registry

PURPOSE

To evaluate the prevalence, risk factors and evolution of diabetes mellitus (DM) after targeted treatment in patients with primary aldosteronism (PA).

METHODS

A retrospective multicenter study of PA patients in follow-up at 27 Spanish tertiary hospitals (SPAIN-ALDO Register).

RESULTS

Overall, 646 patients with PA were included. At diagnosis, 21.2% (n = 137) had DM and 67% of them had HbA1c levels < 7%. In multivariate analysis, family history of DM (OR 4.00 [1.68-9.53]), the coexistence of dyslipidemia (OR 3.57 [1.51-8.43]) and advanced age (OR 1.04 per year of increase [1.00-1.09]) were identified as independent predictive factors of DM. Diabetic patients were on beta blockers (46.7% (n = 64) vs. 27.5% (n = 140), P < 0.001) and diuretics (51.1% (n = 70) vs. 33.2% (n = 169), p < 0.001) more frequently than non-diabetics. After a median follow-up of 22 months [IQR 7.5-63.0], 6.9% of patients developed DM, with no difference between those undergoing adrenalectomy and those treated medically (HR 1.07 [0.49-2.36], p = 0.866). There was also no significant difference in the evolution of glycemic control between DM patients who underwent surgery and those medically treated (p > 0.05).

CONCLUSION

DM affects about one quarter of patients with PA and the risk factors for its development are common to those of the general population. Medical and surgical treatment provides similar benefit in glycemic control in patients with PA and DM.

Willingness to be tested for a secondary cause of hypertension: a survey of the Australian general community

BACKGROUND

Primary aldosteronism (PA) represents the most common and potentially curable cause of secondary hypertension. However, PA is not commonly screened for, and up to 34% of patients who screen positive do not complete the full diagnostic process. This suggests that the diagnostic process may pose a barrier to patients and may contribute to the under-diagnosis of PA.

AIMS

To evaluate the willingness of the Australian general public to undergo testing for secondary causes of hypertension and identify enablers or barriers to testing from the patients' perspective.

METHODS

An online survey containing questions on knowledge and attitudes towards hypertension, willingness to be tested and enablers/barriers towards testing was distributed to the Australian community.

RESULTS

Of 520 adult respondents (mean age 50.4 years, SD 27.3 years; 28.8% hypertensive; 56.0% female), the majority of non-hypertensive and hypertensive respondents (82.7% vs 70.0%; P = 0.03) were willing to undergo testing for a secondary cause of hypertension that involved blood and urine tests. Greater knowledge of hypertensive risk modification strategies and complications was predictive of willingness to be tested, whereas age, sex, education level, geographic location, socio-economic status and cardiovascular comorbidities were not. The top three barriers to testing included fear of a serious underlying condition, lack of belief in further testing and increased stress associated with further testing.

CONCLUSION

A high proportion of patients are willing to engage in testing for a secondary cause of hypertension. Education about the risks associated with hypertension and the testing process may overcome several barriers to testing.

Associated factors and effects of comorbid atrial fibrillation in hypertensive patients due to primary aldosteronism

The incidence of atrial fibrillation (AF) and risk of cardiovascular events are reportedly higher in patients with primary aldosteronism (PA) than essential hypertension. However, associated factors of comorbid AF and cardiovascular events in PA patients after PA treatment remain unclear. This nationwide registration study included PA patients ≥20 years old. Incident cardiovascular events were observed with a mean follow-up of approximately 3 years. A total of 3654 patients with PA were included at the time of analysis. Prevalence of AF was 2.4%. PA patients with AF were older, more frequently male and had longer duration of hypertension than those without AF. No significant difference in basal plasma and adrenal venous aldosterone concentration, renin activity, potassium concentration, confirmatory tests of PA, laterality or surgery rate were seen between groups. Logistic regression analysis showed age, male sex, cardiothoracic ratio, past history of coronary artery disease and heart failure were independent factors associated with AF. PA patients with AF showed a higher frequency of cardiovascular events than those without AF (P < 0.001). Multivariate Cox analyses demonstrated AF in addition to older age, duration of hypertension, body mass index and chronic kidney disease as independent prognostic factors for cardiovascular events after PA treatment. Incidence of cardiovascular events were significantly lower in PA patients with AF than AF patients from the Fushimi registry during follow-up after adjusting age, sex and systolic blood pressure. Early diagnosis of PA may prevent AF and other cardiovascular events in PA patients by shortening the duration of hypertension and appropriate PA treatment.

Underdiagnosis of Primary Aldosteronism: A Review of Screening and Detection

A clinical condition may be missed due to its higher-than-recognized prevalence or inadequate diagnostic screening. Both factors apply to primary aldosteronism, which is woefully underdiagnosed as a cause of hypertension and end-organ damage. Screening tests should be strongly considered for diseases that pose significant morbidity or mortality if left untreated, that have a high prevalence, and that have treatments that lead to improvement or cure. In this review we present the evidence for each of these points. We outline studies that estimate the prevalence of primary aldosteronism in different at-risk populations and how its recognition has changed over time. We also evaluate myriad studies of screening rates for primary aldosteronism and what factors do and do not influence current screening practices. We discuss the ideal conditions for screening, measuring the aldosterone to renin ratio in different populations that use plasma renin activity or direct renin concentration, and the steps for diagnostic workup of primary aldosteronism. Finally, we conclude with potential strategies to implement higher rates of screening and diagnosis of this common, consequential, and treatable disease.

Prevalence of Cortisol Cosecretion in Patients With Primary Aldosteronism: Role of Metanephrine in Adrenal Vein Sampling

CONTEXT

Adrenal venous sampling (AVS) is the gold standard procedure for subtype diagnosis in patients with primary aldosteronism (PA). Cortisol is usually adopted for the normalization of aldosterone levels in peripheral and adrenal samples. However, asymmetrical cortisol secretion can potentially affect the lateralization index, leading to subtype misdiagnosis.

OBJECTIVE

We aimed to assess the prevalence of asymmetrical cortisol secretion in patients undergoing AVS and whether variations in adrenal vein cortisol might influence AVS interpretations. We then evaluated the use of metanephrines for the normalization of aldosterone levels for lateralization index.

METHODS

We retrospectively included 101 patients with PA who underwent AVS: 49 patients underwent unstimulated AVS, while 52 patients underwent both unstimulated and cosyntropin-stimulated AVS. Eighty-eight patients had bilateral successful AVS according to metanephrine ratio. We assessed the prevalence of asymmetrical cortisol secretion through the cortisol to metanephrine (C/M) lateralization index (LI). We then evaluated whether the use of aldosterone to metanephrine (A/M) LI can improve the diagnostic accuracy of AVS compared with aldosterone to cortisol (A/C) LI.

RESULTS

Asymmetrical cortisol secretion is present in 18% of patients with PA. Diagnosis with A/M LI and A/C LI is discordant in 14% of patients: 9% had a diagnosis of unilateral PA with A/M LI instead of bilateral PA with A/C LI and 5% had a diagnosis of bilateral PA with A/M LI instead of unilateral PA.

CONCLUSION

The assessment of metanephrine levels in AVS is useful for the determination of selectivity and lateralization, allowing an accurate diagnosis, especially in patients with asymmetrical cortisol secretion.

Risk of dementia in primary aldosteronism compared with essential hypertension: a nationwide cohort study

BACKGROUND

Although hypertension is a critical risk factor for dementia, the association between primary aldosteronism (PA) and dementia has been scarcely reported. We aimed to investigate whether the risk of dementia in patients with PA was elevated compared with patients with essential hypertension (EH).

METHODS

From the National Health Insurance Claim database in Korea (2003-2017), 3,687 patients with PA (adrenalectomy [ADX], n = 1,339, mineralocorticoid receptor antagonist [MRA] n = 2,348) with no prior dementia were age- and sex-matched at a 1:4 ratio to patients with EH (n = 14,741). The primary outcomes were all-cause dementia events, including Alzheimer's disease, vascular dementia, or other dementia combined with a prescription of one or more medications for dementia (donepezil, galantamine, memantine, or rivastigmine). Multivariable Cox regression models were used to evaluate the hazard ratios (HRs) and 95% confidence intervals for the outcome incidence rates between patients with PA and their EH matches.

RESULTS

During a median follow-up of 5.2 years, there were 156 cases of all-cause dementia (4.2%), 140 cases of Alzheimer's disease (3.8%), and 65 cases of vascular dementia (1.8%). Compared with EH, the risk of all-cause dementia was increased in treated PA (unadjusted hazard ratio [HR] 1.26; p < 0.011). Among PA, MRA group had higher risks of all-cause dementia, especially vascular dementia, adjusted for age, sex, income, comorbidities, and concurrent medication (adjusted HR 1.31; p = 0.027 and adjusted HR 1.62; p = 0.020, respectively) compared to EH. ADX group seemed to have a lower dementia risk than the EH group, but there was no statistical significance after full adjustment. This trend became more prominent when the dementia risks were evaluated from the time of hypertension diagnosis rather than treatment initiation for PA.

CONCLUSION

The findings of this cohort study suggest that PA, especially the MRA group, is associated with an increased risk of dementia. Monitoring cognitive function in PA patients even after treatment initiation might be warranted to prevent dementia.

Primary Aldosteronism Prevalence - An Unfolding Story

Primary aldosteronism (PA) is characterized by dysregulated, renin-independent aldosterone excess. Long perceived as rare, PA has emerged as one of the most common causes of secondary hypertension. Failure to recognize and treat PA results in cardiovascular and renal complications, through processes mediated by both direct target tissue insults and indirectly, by hypertension. PA spans a continuum of dysregulated aldosterone secretion, which is typically recognized in late stages after treatment-resistant hypertension and cardiovascular and/or renal complications develop. Determining the precise disease burden remains challenging due to heterogeneity in testing, arbitrary thresholds, and populations studied. This review summarizes the reports on PA prevalence among the general population and in specific high-risk subgroups, highlighting the impact of rigid versus permissive criteria on PA prevalence perception.

Screening for Primary Aldosteronism Among Hypertensive Adults with Obstructive Sleep Apnea: A Retrospective Population-Based Study

BACKGROUND

Hypertension plus obstructive sleep apnea (OSA) is recommended in some guidelines as an indication to screen for primary aldosteronism (PA), yet prior data has brought the validity of this recommendation into question. Given this context, it remains unknown whether this screening recommendation is being implemented into clinical practice.

METHODS

We conducted a population-based retrospective cohort study of all adult Ontario (Canada) residents with hypertension plus OSA from 2009 to 2020 with follow-up through 2021 utilizing provincial health administrative data. We measured the proportion of individuals who underwent PA screening via the aldosterone-to-renin ratio by year. We further examined screening rates among patients with hypertension plus OSA by the presence of concurrent hypokalemia and resistant hypertension. Clinical predictors associated with screening were assessed via Cox regression modeling.

RESULTS

The study cohort included 53,130 adults with both hypertension and OSA, of which only 634 (1.2%) underwent PA screening. Among patients with hypertension, OSA, and hypokalemia, the proportion of eligible patients screened increased to 2.8%. Among patients ≥65 years with hypertension, OSA, and prescription of ≥4 antihypertensive medications, the proportion of eligible patients screened was 1.8%. Older age was associated with a decreased likelihood of screening while hypokalemia and subspecialty care with internal medicine, cardiology, endocrinology, or nephrology were associated with an increased likelihood of screening. No associations with screening were identified with sex, rural residence, cardiovascular disease, diabetes, or respirology subspecialty care.

CONCLUSIONS

The population-level uptake of the guideline recommendation to screen all patients with hypertension plus OSA for PA is exceedingly low.

[Clinical Characteristics of Obstructive Sleep Apnea and Comorbid Primary Aldosteronism]

Objective

To explore the characteristics of patients with obstructive sleep apnea (OSA) and comorbid primary aldosteronism (PA) and to explore the relevant factors affecting plasma aldosterone concentration.

Methods

A total of 105 patients diagnosed with PA and admitted at West China Hospital, Sichuan University between January 2016 and December 2021 were retrospectively analyzed. The subjects were divided into a PA with comorbid snoring group (n=20) and a PA with comorbid OSA group (n=85) based on the results of polysomnography (PSG). The PA with comorbid OSA group was further divided into mild, moderate, and severe subgroups according to the apnea-hypopnea index (AHI). A total of 85 outpatients diagnosed with OSA were included as the control group. Demographic, clinical, biochemical, and PSG data were compared between the groups.

Results

Compared with patients with only OSA, a significantly higher proportion of patients with OSA and comorbid PA had hypertension and elevated levels of systolic and diastolic blood pressure (P<0.05). In addition, patients with OSA and comorbid PA had significantly increased AHI and significantly decreased mean oxygen saturation and sleep efficiency (P<0.05). The more severe the OSA was, the higher levels of BMI, cholesterol, low-density lipoprotein, and uric acid the PA patients had. Linear regression analysis showed that the lowest oxygen saturation (β=－0.222, P=0.045) was negatively correlated with plasma aldosterone concentration.

Conclusion

Comorbidity with PA can aggravate the clinical manifestations of OSA, while OSA further disrupted the metabolism of lipids and uric acid in PA patients. Plasma aldosterone concentrations in patients with comorbid OSA and PA were affected by the lowest oxygen saturation level.

Implementation of a formal sleep center-based screening protocol for primary aldosteronism in patients with obstructive sleep apnea

BACKGROUND

There is a bidirectional association between primary aldosteronism and obstructive sleep apnea, with evidence suggesting that the treatment of primary aldosteronism can reduce obstructive sleep apnea severity. Current guidelines recommend screening for primary aldosteronism in patients with comorbid hypertension and obstructive sleep apnea, identifying potential candidates for treatment. However, emerging data suggest current screening practices are unsatisfactory. Moreover, data regarding the true incidence of primary aldosteronism among this population are limited. This study aimed to assess the primary aldosteronism screening rate among patients with obstructive sleep apnea and hypertension at our institution and estimate the prevalence of primary aldosteronism among this population.

METHODS

Sleep studies conducted at our institution between January and September 2021 were retrospectively reviewed. Adult patients with a sleep study diagnostic of obstructive sleep apnea (respiratory disturbance index ≥5) and a diagnosis of hypertension were included. Patient medical records were reviewed and laboratory data of those with biochemical screening for primary aldosteronism were assessed by an experienced endocrinologist. Screening rates were compared before and after initiation of a screening protocol in accordance with the 2016 Endocrine Society guidelines.

RESULTS

A total of 1,005 patients undergoing sleep studies were reviewed; 354 patients had comorbid obstructive sleep apnea and hypertension. Patients were predominantly male (67%), with a mean age of 58 years (standard deviation = 12.9) and mean body mass index of 34 (standard deviation = 8.1). The screening rate for primary aldosteronism among included patients was 19% (n = 67). The screening rate was significantly higher after initiation of a dedicated primary aldosteronism screening protocol (23% vs 12% prior; P = .01). Fourteen screens (21%) were positive for primary aldosteronism, whereas 45 (67%) were negative and 8 (12%) were indeterminate. Four had prior abdominal cross-sectional imaging, with 3 revealing an adrenal adenoma. Compared with patients without primary aldosteronism, patients with positive primary aldosteronism screens were more likely to have a history of hypokalemia (36% vs 4.4%; P = .002). The frequency of hyperlipidemia, diabetes mellitus, and left ventricular hypertrophy did not differ between patients with positive versus negative screens.

CONCLUSION

Current screening practices for primary aldosteronism among patients with comorbid obstructive sleep apnea and hypertension are suboptimal. Patients evaluated at sleep centers may represent an optimal population for screening, as the prevalence of primary aldosteronism among this cohort appears high.

Risky business: a single-centre cross-sectional analysis of calculated cardiovascular risk in patients with primary aldosteronism and essential hypertension

OBJECTIVES

Primary aldosteronism (PA), the most common endocrine cause of hypertension, is associated with a higher risk of cardiovascular disease (CVD) than blood pressure (BP)-matched essential hypertension (EH). We aimed to compare the calculated risks of CVD in patients who had hypertension with PA or EH using CVD risk calculators, hypothesising that they will fail to recognise the increased CVD risk in PA.

DESIGN

Cross-sectional analysis.

SETTING

An endocrine hypertension service in Victoria, Australia.

PARTICIPANTS

Patients who had hypertension without CVD referred for the investigation of hypertension.

OUTCOME MEASURES

Calculated 5-year or 10-year CVD risk as predicted by the National Vascular Disease Prevention Alliance (NVDPA) algorithm, Framingham Risk Score, Pooled Cohort Equations and QRISK3.

RESULTS

Those with PA (n=128) and EH (n=133), did not differ significantly in their calculated CVD risks with the NVDPA algorithm (moderate-to-high 5-year risk 36/100 vs 45/99, p=0.17); the Framingham Risk Score (median 10-year risk 7.72% (4.43%-12.95%) vs 6.84% (3.85%-10.50%), p=0.14); the Pooled Cohort Equations (median 10-year risk 9.45% (4.36%-15.37%) vs 7.90% (2.09%-14.73%), p=0.07); and QRISK3 (median 10-year risk 11.31% (7.22%-20.29%) vs 12.47% (5.10%-19.93%), p=0.51). Similarities persisted on regression analyses accounting for systolic BP.

CONCLUSIONS

CVD risk algorithms do not reflect the increased risk of CVD in patients with PA, and likely underestimate the true risk of CVD among those with PA. Screening for PA, in addition to using the CVD risk algorithm in patients who had hypertension, may facilitate the targeted treatment of PA and minimisation of cardiovascular risk in affected individuals.

Primary aldosteronism - a multidimensional syndrome

Primary aldosteronism is a common cause of hypertension and is a risk factor for cardiovascular and renal morbidity and mortality, via mechanisms mediated by both hypertension and direct insults to target organs. Despite its high prevalence and associated complications, primary aldosteronism remains largely under-recognized, with less than 2% of people in at-risk populations ever tested. Fundamental progress made over the past decade has transformed our understanding of the pathogenesis of primary aldosteronism and of its clinical phenotypes. The dichotomous paradigm of primary aldosteronism diagnosis and subtyping is being redefined into a multidimensional spectrum of disease, which spans subclinical stages to florid primary aldosteronism, and from single-focal or multifocal to diffuse aldosterone-producing areas, which can affect one or both adrenal glands. This Review discusses how redefining the primary aldosteronism syndrome as a multidimensional spectrum will affect the approach to the diagnosis and subtyping of primary aldosteronism.

Cortisol-producing adenoma-related somatic mutations in unilateral primary aldosteronism with concurrent autonomous cortisol secretion: their prevalence and clinical characteristics

OBJECTIVE

Concurrent autonomous cortisol secretion (ACS) in patients with primary aldosteronism (PA) is being reported more frequently. Several somatic mutations including PRKACA, GNAS, and CTNNB1 were identified in cortisol-producing adenomas (CPAs). The presence of these mutations in unilateral PA (uPA) patients concurrent with ACS (uPA/ACS) is not well known. This study aimed to investigate the prevalence of these mutations and their clinical vs pathological characteristics in uPA/ACS.

DESIGN

This is a retrospective cohort study.

METHODS

Totally 98 uPA patients from the Taiwan Primary Aldosteronism Investigation registry having overnight 1-mg dexamethasone suppression test (DST) and adrenalectomy from 2016 to 2018 were enrolled. Their adrenal tumors were tested for PRKACA, GNAS, and CTNNB1 mutations.

RESULTS

11 patients had CPA-related mutations (7 PRKACA and 4 GNAS). The patients carrying these mutations had higher post-DST cortisol (5.6 vs 2.6 μg/dL, P = 0.003) and larger adenoma (2.2 ± 0.3 vs 1.9 ± 0.7 cm, P = 0.025). Adenomas with these mutations had a higher prevalence of non-classical uPA (72.7% vs 26.3%, P = 0.014). Numerically, slightly more complete clinical success of uPA patients with these mutations was noticed after adrenalectomy, although it was statistically non-significant. Post-DST cortisol levels, adenoma size >1.9 cm, and the interaction of adenoma size >1.9 cm with potassium level were found to be associated with the presence of these mutations.

CONCLUSION

Our study showed that CPA-related mutations were detected in 36.7% of uPA/ACS adenomas. The presence of these mutations was associated with higher post-DST cortisol levels, larger adenoma sizes, and a high percentage of non-classical uPA. However, these mutations did not significantly affect the clinical and biochemical outcomes after adrenalectomy of uPA/ACS patients but they showed a better trend.

Who should be screened for primary aldosteronism? A comprehensive review of current evidence

Arterial hypertension is a major risk factor for cardiovascular disease. The prevalence of primary aldosteronism (PA) ranges from 5% to 10% in the general hypertensive population and is regarded as one of the most common causes of secondary hypertension. There are two major causes of PA: bilateral adrenal hyperplasia and aldosterone-producing adenoma. The diagnosis of PA comprises screening, confirmatory testing, and subtype differentiation. The Endocrine Society Practice Guidelines for the diagnosis and treatment of PA recommends screening of patients at an increased risk of PA. These categories include patients with stage 2 and 3 hypertension, drug-resistant hypertension, hypertensive with spontaneous or diuretic-induced hypokalemia, hypertension with adrenal incidentaloma, hypertensive with a family history of early onset hypertension or cerebrovascular accident at a young age, and all hypertensive first-degree relatives of patients with PA. Recently, several studies have linked PA with obstructive sleep apnea and atrial fibrillation unexplained by structural heart defects and/or other conditions known to cause the arrhythmia, which may be partly responsible for the higher rates of cardiovascular and cerebrovascular accidents in patients with PA. The aim of this review is to discuss which patients should be screened for PA, focusing not only on well-established guidelines but also on additional groups of patients with a potentially higher prevalence of PA, as has been reported in recent research.

Cardiac Structure and Function Across the Spectrum of Aldosteronism: the Atherosclerosis Risk in Communities Study

BACKGROUND

Aldosterone production and mineralocorticoid receptor activation are implicated in myocardial fibrosis and cardiovascular events.

METHODS

Cardiac structure and function were assessed in 4547 participants without prevalent heart failure (HF) in the ARIC study (Atherosclerosis Risk in Communities), with echocardiography, aldosterone, and plasma renin activity measurement (2011-2013). Subjects were characterized by plasma renin activity as suppressed (≤0.5 ng/mL per hour) or unsuppressed (>0.5 ng/mL per hour). Cross-sectional relationships with cardiac structure and function, and longitudinal relationships with outcomes (HF hospitalization; HF and all-cause death; HF, death, myocardial infarction, and stroke; and incident atrial fibrillation) were assessed. Models were adjusted for demographic and anthropometric characteristics and additively, for blood pressure and antihypertensives.

RESULTS

Evidence of primary aldosteronism physiology was prevalent (11.6% with positive screen) and associated with echocardiographic parameters. Renin suppression was associated with greater left ventricular mass, left ventricular volumes, and left atrial volume index, and a lower E/A ratio (adjusted P<0.001 for all). Higher aldosterone was associated with greater left ventricular mass and lower global longitudinal strain and lateral E'. The highest tertile of aldosterone was associated with a hazard ratio of 1.37 (95% CI, 1.06-1.77; 5.5-year follow-up) for incident atrial fibrillation relative to the lowest. Renin suppression was associated with HF (hazard ratio, 1.34 [95% CI, 1.05-1.72]; 7.3-year follow-up), although these relationships did not remain statistically significant after additional adjustment for hypertension.

CONCLUSIONS

Renin suppression and aldosterone excess, consistent with primary aldosteronism pathophysiology, were associated with cardiac structural and functional alterations and may represent an early target for mitigation of fibrosis with mineralocorticoid receptor antagonists.

Newly diagnosed diabetes mellitus is a risk factor for cardiocerebrovascular events in primary aldosteronism

OBJECTIVE

To explore the prevalence and clinical significance of newly diagnosed diabetes mellitus (DM) in patients with primary aldosteronism (PA). Investigating the risk factors for cardiocerebrovascular disease (CCVD) will guide strategies for reducing CCVD in patients with PA.

METHODS

We retrospectively included 729 PA patients without DM and conducted oral glucose tolerance tests.

RESULTS

We found that 15.0% of PA patients had newly diagnosed DM. The DM prevalence increased with elevated aldosterone levels [OR = 3.20 (1.77, 5.78), P value < 0.001]. The rate of CCVD in newly diagnosed diabetic PA patients was higher than that in nondiabetic PA patients at diagnosis (11.9% vs. 5.0%, P = 0.005). Furthermore, multivariate logistic analysis revealed that HT duration [1.055 (1.002,1.111), P = 0.041] and newly diagnosed DM [2.600 (1.072,6.303), P = 0.034] were significantly associated with CCVD in PA patients.

CONCLUSION

The prevalence of newly diagnosed DM in PA patients was higher than that in the general population. Aldosterone level was an independent risk factor for DM not for CCVD. CCVD was correlated with longer HT duration and newly diagnosed DM. Therefore, it is crucial to screen DM at the diagnosis in PA patients.

Assessment and Management of Primary Aldosteronism in Pregnancy: A Case-Control Study

CONTEXT

Primary aldosteronism (PA) is a common secondary cause of hypertension. Literature regarding PA in pregnancy has demonstrated poor outcomes.

OBJECTIVE

Compare the management and outcomes of PA in pregnancy to both high and low-risk matched controls.

METHODS

This was a case-control trial conducted in a network of metropolitan hospitals in Sydney, Australia. PA women (positive salt suppression test) with singleton pregnancies delivered after 20 weeks' gestation were matched to women with high- and low-risk pregnancies. Management outcomes included pre-eclampsia prophylaxis and antihypertensive medications required prenatally, antenatally, and postnatally. Maternal outcomes included incidence of pre-eclampsia, gestational diabetes, hypokalemia, mode of delivery, and length of stay postpartum. Neonatal outcomes included gestation, birthweight, intensive care unit admission, and length of stay.

RESULTS

Fifty-nine women with 60 pregnancies were included (20 PA, 20 high risk, and 20 low risk). The number of antihypertensive medications women with PA took prepregnancy was similar to the high-risk group. A similar proportion of women in the PA and high-risk groups were prescribed pre-eclampsia prophylaxis and developed pre-eclampsia. Even after adjustment for several factors, PA was not independently associated with pre-eclampsia development. Women with PA had higher antihypertensive requirements and a longer stay in hospital postpartum than the high-risk group (both P = .02). There was no difference in neonatal adverse outcomes. Four women took epleronone during pregnancy without any adverse effects noted.

CONCLUSION

Women with PA required more antihypertensives and had a longer postpartum length of stay than matched high-risk women, but similar rates of pre-eclampsia. There was no difference in the rate of neonatal intensive care admissions or adverse outcomes for neonates.

Autonomous cortisol secretion is associated with worse arterial stiffness and vascular fibrosis in primary aldosteronism: a cross-sectional study with follow-up data

OBJECTIVE

The presence of autonomous cortisol secretion (ACS) in patients with primary aldosteronism (PA) is common and potentially associated with poor outcomes. The aim of this study was to investigate the association between ACS and vascular remodeling in PA patients.

DESIGN AND METHODS

We prospectively enrolled 436 PA patients from October 2006 to November 2019. ACS (defined as a cortisol level >1.8 μg/dL after a 1 mg dexamethasone suppression test) was detected in 23% of the PA patients. Propensity score matching (PSM) with age, sex, systolic and diastolic blood pressure was performed. The brachial-ankle pulse wave velocity (baPWV) was examined at baseline and 1 year after targeted treatment. Small arteries of periadrenal fat in 46 patients were stained with Picro Sirus red to quantify the severity of vascular fibrosis.

RESULTS

After PSM, the PA patients with ACS had a significantly higher prevalence of diabetes mellitus, higher plasma aldosterone concentration and higher aldosterone-to-renin ratio. The baseline mean baPWV was also significantly higher in the PA patients with ACS. After multivariable regression analysis, the presence of ACS was a significant predictor of worse baseline mean baPWV (β: 235.745, 95% CI: 59.602-411.888, P = 0.010). In addition, the PA patients with ACS had worse vascular fibrosis (fibrosis area: 25.6 ± 8.4%) compared to those without ACS (fibrosis area: 19.8 ± 7.7%, P = 0.020). After 1 year of PA treatment, baPWV significantly improved in both groups.

CONCLUSION

The presence of ACS in PA patients is associated with worse arterial stiffness and vascular remodeling.

Evolution of the cardiometabolic profile of primary hyperaldosteronism patients treated with adrenalectomy and with mineralocorticoid receptor antagonists: results from the SPAIN-ALDO Registry

OBJECTIVE

To analyze the evolution of the cardiometabolic profile of patients with primary hyperaldosteronism (PA) after the treatment with surgery and with mineralocorticoid receptor antagonists (MRA).

DESIGN

Retrospective multicentric study of patients with PA on follow-up in twelve Spanish centers between 2018 and 2020.

RESULTS

268 patients with PA treated by surgery (n = 100) or with MRA (n = 168) were included. At baseline, patients treated with surgery were more commonly women (54.6% vs 41.7%, P = 0.042), had a higher prevalence of hypokalemia (72.2% vs 58%, P = 0.022) and lower prevalence of obesity (37.4% vs 51.3%, P = 0.034) than patients treated with MRA. Adrenalectomy resulted in complete biochemical cure in 94.0% and clinical response in 83.0% (complete response in 41.0% and partial response in 42.0%). After a median follow-up of 23.6 (IQR 9.7-53.8) months, the reduction in blood pressure (BP) after treatment was similar between the group of surgery and MRA, but patients surgically treated reduced the number of antihypertensive pills for BP control more than those medically treated (∆antihypertensives: -1.3 ± 1.3 vs 0.0 ± 1.4, P < 0.0001) and experienced a higher increased in serum potassium levels (∆serum potassium: 0.9 ± 0.7 vs 0.6 ± 0.8mEq/ml, P = 0.003). However, no differences in the risk of the onset of new renal and cardiometabolic comorbidities was observed between the group of surgery and MRA (HR = 0.9 [0.5-1.5], P = 0.659).

CONCLUSION

In patients with PA, MRA and surgery offer a similar short-term cardiovascular protection, but surgery improves biochemical control and reduces pill burden more commonly than MRA, and lead to hypertension cure or improvement in up to 83% of the patients.

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.

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.

Differences in Glycemic Abnormalities Between Primary Aldosteronism and Essential Hypertension: A Systematic Review and Meta-Analysis

Background

The relationship of glycemic abnormalities between primary aldosteronism (PA) patients and essential hypertension (EH) patients is still debatable. This meta-analysis aimed to explore differences in the prevalence of glycemic abnormalities and levels of abnormal glucose metabolism in PA and EH patients.

Methods

A search was performed using PubMed, Scopus, Cochrane and Web of Science databases from their inception through January 2022. Inclusion criteria for this study were 1) observational studies which contained specific data of interest, 2) studies including data which compared adult PA and EH patients and 3) studies which used appropriate methods to diagnose PA. Risk ratio (RR) or standardized mean difference (SMD) with a 95% confidence interval (95% CI) was calculated.

Results

Twenty-six studies involving 53,186 patients were included in the meta-analysis. Patients with PA demonstrated significantly higher overall incidence of glycemic abnormalities than patients with EH [RR 1.54; 95% CI (1.20,1.98)]. Risk of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in PA patients were higher than in EH patients [RR 1.27; 95%CI (1.08, 1.49) and RR 2.99; 95%CI (1.74, 5.16), respectively]. There was no statistically significant difference of risk between these groups for impaired fasting glucose (IFG) [RR 1.70; 95%CI (0.55, 5.26)]. Moderate heterogeneity was observed in overall glycemic abnormalities outcomes. A high level of heterogeneity was observed for IFG, while the level was low for DM and IGT.

Conclusions

PA patients have a higher risk of glycemic abnormalities than in EH patients. Further study should be conducted to investigate underlying mechanisms of glycemic abnormalities in PA.

Systematic Review Registration

www.inplasy.com, INPLASY, identifier 202220004.

Screening for primary aldosteronism is underutilised in patients with chronic kidney disease

BACKGROUND

Primary aldosteronism (PA) is the most common and potentially curable endocrine cause of secondary hypertension, and carries a worse prognosis than essential hypertension. Despite the high prevalence of hypertension in patients with chronic kidney disease (CKD), the screening rates for primary aldosteronism in CKD are unknown.

METHODS

In this study, we retrospectively reviewed medical records of 1627 adults who presented to the nephrology clinics of 2 tertiary hospitals in Melbourne, Australia, between 2014 and 2019. In addition to assessing the pattern of screening, we also evaluated patient-specific factors associated with the decision to test for primary aldosteronism. Patients were excluded from the final analysis if they did not have CKD, had an organ transplant, had end stage renal failure, or had insufficient data or follow-up.

RESULTS

Of the 600 patients included in the analysis, 234 (39%) had an indication for screening for primary aldosteronism based on recommendations made by the Endocrine Society. However, only 33 (14%) were tested. They were younger, had a higher mean systolic blood pressure, better renal function, and lower mean serum potassium than those who were indicated but not screened. Of the 33 screened patients, an elevated aldosterone-to-renin ratio was noted in 8 patients and a diagnosis of primary aldosteronism was made in 4 patients.

CONCLUSIONS

The screening rate for primary aldosteronism is low in a CKD population, especially in patients who are older, have a lower eGFR and normal serum potassium. The consequences of undiagnosed primary aldosteronism in this select population may be substantial due to the cardiovascular and renal sequelae associated with untreated disease.

Clinical Characteristics of Target Organ Damage in Primary Aldosteronism with or without Metabolic Syndrome

The aim of this study is to investigate the prevalence of metabolic disorders in patients with primary aldosteronism (PA) and target organ damage (TOD) in different subtypes of patients with PA with or without metabolic syndrome (MS). Patients with PA were screened out from those with secondary hypertension and then subtyped via adrenal venous sampling (AVS). Baseline clinical characteristics (blood pressure, blood glucose, abdominal circumference, and lipid profile) were collected for the diagnosis of MS. Organ damage was evaluated according to cardiac and carotid ultrasound and urine microalbumin measurements. In all 261 patients with PA, 113 patients had concomitant MS and experienced more severe cardiac hypertrophy and increased intima-media thickness (IMT). The incidence of MS and diabetes mellitus (DM) had no statistic difference between the two groups, moreover, the rates of TOD were not different except microalbuminuria. However, metabolic disorders caused more remarkable TOD in PA patients with unilateral hypersecretion. It showed that cardiac hypertrophy was associated with obesity while microalbuminuria was related to plasma aldosterone concentration (PAC) in PA patients. In this retrospective study, our findings suggest that the effect of metabolic disorders on organ damage is more remarkable in patients with unilateral PA.

Primary aldosteronism and obstructive sleep apnea: What do we know thus far?

Both primary aldosteronism and obstructive sleep apnea are well-known causes of hypertension and contribute to increased cardiovascular morbidity and mortality independently. However, the relationship between these two entities remains unclear, with studies demonstrating contradictory results. This review aims to collate and put into perspective current available research regarding the association between primary aldosteronism and obstructive sleep apnea. The relationship between these two entities, clinical characteristics, clinical implications, outcomes of treatment, potential causal links and mechanisms are hereby presented.

Online prediction model for primary aldosteronism in patients with hypertension in Chinese population: A two-center retrospective study

BACKGROUND

The prevalence of primary aldosteronism (PA) varies from 5% to 20% in patients with hypertension but is largely underdiagnosed. Expanding screening for PA to all patients with hypertension to improve diagnostic efficiency is needed. A novel and portable prediction tool that can expand screening for PA is highly desirable.

METHODS

Clinical characteristics and laboratory data of 1,314 patients with hypertension were collected for modeling and randomly divided into a training cohort (919 of 1,314, 70%) and an internal validation cohort (395 of 1,314, 30%). Additionally, an external dataset (n = 285) was used for model validation. Machine learning algorithms were applied to develop a discriminant model. Sensitivity, specificity, and accuracy were used to evaluate the performance of the model.

RESULTS

Seven independent risk factors for predicting PA were identified, including age, sex, hypokalemia, serum sodium, serum sodium-to-potassium ratio, anion gap, and alkaline urine. The prediction model showed sufficient predictive accuracy, with area under the curve (AUC) values of 0.839 (95% CI: 0.81-0.87), 0.814 (95% CI: 0.77-0.86), and 0.839 (95% CI: 0.79-0.89) in the training set, internal validation, and external validation set, respectively. The calibration curves exhibited good agreement between the predictive risk of the model and the actual risk. An online prediction model was developed to make the model more portable to use.

CONCLUSION

The online prediction model we constructed using conventional clinical characteristics and laboratory tests is portable and reliable. This allowed it to be widely used not only in the hospital but also in community health service centers and may help to improve the diagnostic efficiency of PA.

Primary Aldosteronism More Prevalent in Patients With Cardioembolic Stroke and Atrial Fibrillation

BACKGROUND

Primary aldosteronism (PA) is the most common cause of secondary hypertension, and patients are at an increased risk of atrial fibrillation (AF) and stroke. We assessed the prevalence of PA in patients with recent stroke.

METHODS

We recruited 300 patients admitted to an acute stroke unit with diagnosis of cerebrovascular accident (haemorrhagic/ischaemic) or transient ischaemic attack. Three months post-stroke, plasma renin and aldosterone were measured. Patients with an elevated aldosterone-renin ratio proceeded to the confirmatory saline loading test.

RESULTS

Twenty-six of 192 (14%) patients had an elevated aldosterone-renin ratio. Three of 14 patients who proceeded to saline loading were confirmed with PA (post-saline aldosterone >138 pmol/l). Another three patients were classified as confirmed/likely PA based on the markedly elevated aldosterone-renin ratio and clinical characteristics. The overall prevalence of PA amongst stroke patients with hypertension was 4.0% (95% confidence interval (CI): 0.9%-7.1%). Prevalence of PA was higher amongst patients with cardioembolic stroke, 11% (95% CI: 1.3%-33%), resistant hypertension, 11% (95% CI: 0.3%-48%), and hypertension and AF, 30% (95%CI: 6.7%-65%). If only young patients or those with hypokalaemia were screened for PA, half of our patients with PA would not have been diagnosed. Our decision tree identified that stroke patients with AF and diastolic blood pressure ≥83mmHg were most likely to have PA.

CONCLUSION

We found that amongst hypertensive patients with stroke, PA was more prevalent in those with AF, or cardioembolic stroke. Screening for PA should be considered for all patients with stroke.

Incidence of Primary Aldosteronism in Patients with Hypokalemia (IPAHK+): Study Design and Baseline Characteristics

Hypokalemia plays a central role for case finding, course, treatment decision, and prognosis of patients with primary aldosteronism. However, to date there is a lack of high-level evidence about the incidence of primary aldosteronism in hypokalemic patients. The IPAHK⁺study is an epidemiological, cross-sectional, monocentric study to provide evidence on the incidence of PA in a hypokalemic population. The aim of the current analysis was to describe the baseline characteristics of the first 100 patients eligible for study inclusion. The recruitment of patients with hypokalemia (≤3 mmol/l) is carried out continuously on a referral-basis by the central laboratory of the University Hospital Zurich through an automated suitability testing and data delivery system. The careful evaluation of the first 100 reported patients was based on the available reporting system. Out of 28 140 screened patients, 222 (0.79%) were identified with a serum potassium value of≤3 mmol/l (mean 2.89±0.02 mmol/l). Mean potassium levels were slightly lower in non-hypertensive subjects compared to hypertensive subjects (mean difference 0.07 mmol/l, p=0.033), while no significant difference was found between the sexes and patients with and without the diagnosis of primary aldosteronism, atrial fibrillation, or the use of diuretics. The incidence of PA was 4% in the total population studied and 7.5% in the subgroup of hypertensive patients. In conclusion, the continuous enrollment of patients from the IPHAK⁺hypokalemia registry into the IPAHK⁺trial will provide evidence about the actual incidence of primary aldosteronism in a hypokalemic outpatient population.