Primary aldosteronism (PA) is a common form of endocrine hypertension previously believed to account for less than 1% of hypertensive patients. Hypokalemia was considered a prerequisite for pursuing diagnostic tests for PA. Recent studies applying the plasma aldosterone/plasma renin activity ratio (ARR) as a screening test have reported a higher prevalence. This study is a retrospective evaluation of the diagnosis of PA from clinical centers in five continents before and after the widespread use of the ARR as a screening test. The application of this strategy to a greater number of hypertensives led to a 5- to 15-fold increase in the identification of patients affected by PA. Only a small proportion of patients (between 9 and 37%) were hypokalemic. The annual detection rate of aldosterone-producing adenoma (APA) increased in all centers (by 1.3–6.3 times) after the wide application of ARR. Aldosterone-producing adenomas constituted a much higher proportion of patients with PA in the four centers that employed adrenal venous sampling (28–50%) than in the center that did not (9%). In conclusion, the wide use of the ARR as a screening test in hypertensive patients led to a marked increase in the detection rate of PA.

Background: Primary aldosteronism (PA), a primary adrenal disorder leading to excessive aldosterone production by one or both adrenal glands, is a common cause of hypertension. It is associated with an increased risk of cardiovascular complications compared with primary hypertension. Despite effective methods for diagnosing and treating PA, it remains markedly underdiagnosed and undertreated. Objective: To develop an updated guideline that provides a practical, clinical approach to identifying and managing PA to improve diagnosis rates and encourage targeted treatment. Methods: The Guideline Development Panel (GDP), composed of a multidisciplinary panel of clinical experts and experts in systemic review methodology, used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to define 10 questions related to the diagnosis and treatment of PA. Systematic reviews were conducted for each question. The GDP used the GRADE Evidence to Decision (EtD) framework to consider contextual factors, such as stakeholder values and preferences, costs and required resources, cost-effectiveness, acceptability, feasibility, and the potential impact on health equity. Results: We suggest that all individuals with hypertension be screened for PA by measuring aldosterone and renin and determining the aldosterone to renin ratio, and that subsequent clinical care be guided by the results. We suggest that individuals with PA receive PA-specific therapy, either medical or surgical. In individuals who screen positive for PA, we suggest (1) commencement of PA-specific medical therapy in individuals who do not desire or are not candidates for surgery and in situations where the probability of lateralizing PA (excess aldosterone produced by one adrenal) is low based on screening results; and (2) aldosterone suppression testing in situations when screening results indicate an intermediate probability for lateralizing PA and individualized decision making confirms a desire to pursue eligibility for surgical therapy. In those who test positive by aldosterone suppression testing, and in those in whom screening results show a high probability of lateralizing PA (obviating the need for aldosterone suppression testing), we suggest adrenal lateralization with computed tomography scanning and adrenal venous sampling prior to deciding the treatment approach (medical vs surgical). In all individuals with PA and an adrenal adenoma, we suggest performing a 1-mg overnight dexamethasone suppression test. We suggest the use of mineralocorticoid receptor antagonists (MRAs) over epithelial sodium-channel (ENaC) inhibitors in the medical treatment of PA. We suggest the use of spironolactone over other MRAs, given its lower cost and greater availability; however, all MRAs, when titrated to equivalent potencies, are anticipated to have similar efficacy in treating PA. Thus, MRAs with greater mineralocorticoid receptor specificity and fewer androgen/progesterone receptor-mediated side effects may be preferred in some situations. In individuals receiving MRA therapy, we suggest monitoring renin and, in those whose hypertension remains uncontrolled and renin is suppressed, titrating the MRA to increase renin. Conclusion: These recommendations provide a practical framework for the diagnosis and treatment of PA. They are based on currently available literature and take into consideration outcomes that are important to key stakeholders. The goal is to increase identification of individuals with PA and, by initiating PA-specific medical or surgical therapy, improve blood pressure control and reduce PA-associated adverse cardiovascular events. The guidelines also highlight important knowledge gaps in PA diagnosis and management.

Aldosterone plays a detrimental role on the cardiovascular system and PA patients display a higher risk of events compared with EH. The objectives of the study were to compare cardio- and cerebrovascular events in patients with primary aldosteronism (PA) and matched essential hypertension (EH). We retrospectively compared the percentage of patients experiencing events at baseline and during a median follow-up of 12 years in 270 PA patients case-control matched 1:3 with EH patients and in PA subtypes [aldosterone-producing adenoma (n = 57); bilateral adrenal hyperplasia (n = 213)] vs matched EH. A significantly higher number of PA patients experienced cardiovascular events over the entire period of the study (22.6% vs 12.7%, P < .001). At the diagnosis of PA, a higher number of patients had experienced total events (14.1% vs 8.4% EH, P = .007); furthermore, during the follow-up period, PA patients had a higher rate of events (8.5% vs 4.3% EH, P = .008). In particular, stroke and arrhythmias were more frequent in PA patients. During the follow-up, a higher percentage of PA patients developed type 2 diabetes. Parameters that were independently associated with the occurrence of all events were age, duration of hypertension, systolic blood pressure, presence of diabetes mellitus, and PA diagnosis. After division into PA subtypes, patients with either aldosterone-producing adenoma or bilateral adrenal hyperplasia displayed a higher rate of events compared with the matched EH patients. This study demonstrates in a large population of patients the pathogenetic role of aldosterone excess in the cardiovascular system and thus the importance of early diagnosis and targeted PA treatment.

Primary aldosteronism is a specifically treatable and potentially curable form of secondary hypertension. The aldosterone/plasma renin activity ratio (ARR) is routinely used as a screening test. Antihypertensive therapy can interfere with the interpretation of this parameter, but a correct washout period can be potentially harmful. We have investigated the effects of therapy with atenolol, amlodipine, doxazosin, fosinopril, and irbesartan on the ARR in a group of 230 patients with suspected primary aldosteronism. The percent change from control of ARR in patients taking amlodipine was −17%±32; atenolol, 62%±82; doxazosin, −5%±26; fosinopril, −30%±24; and irbesartan, −43%±27. The ARR change induced by atenolol was significantly higher compared with that induced by all other drugs ( P <0.0001), and the ARR change induced by irbesartan was significantly lower than that induced by doxazosin ( P <0.0001). One of 55 patients from the group taking amlodipine (1.8%) and 4/17 of the patients taking irbesartan (23.5%) gave a false-negative ARR (<50). None of the patients of the groups taking fosinopril, doxazosin, and atenolol displayed a false-negative ARR. Doxazosin and fosinopril can be used in hypertensive patients who need to undergo aldosterone and PRA measurement for the diagnosis of primary aldosteronism; amlodipine gave a very small percentage of false-negative diagnoses. β-Blockers also do not interfere with the diagnosis of primary aldosteronism, but they can be responsible for an increased rate of false-positive ARRs. The high rate of false-negative diagnoses in patients undergoing irbesartan treatment requires confirmation in a higher number of patients.