CHICAGO — For millions of adults worldwide, a diagnosis of hypertension serves as a standard health milestone, often managed with routine lifestyle modifications and common antihypertensive medications. However, a significant subset of these patients may be battling a far more complex condition that remains largely invisible to the medical establishment: primary aldosteronism (PA).
New research presented at ENDO 2026, the annual meeting of the Endocrine Society, suggests that the current clinical approach to hypertension is leaving a vast population of patients at risk. A large-scale, real-world cohort study has revealed that only a fraction of patients newly diagnosed with hypertension undergo the necessary screening for primary aldosteronism, despite guidelines explicitly recommending it for all such individuals.
The Hidden Epidemic: Main Facts of the Study
The study, led by Diana Grace Varghese, MD, of the University of Maryland in Rockville, analyzed an expansive dataset of 2.5 million adults diagnosed with incident hypertension between 2011 and 2023. The findings were stark: only 18,787 of these patients—a mere 0.76%—received the diagnostic screening required to identify primary aldosteronism.
Among those who were screened and had available biochemical data, 8.7% tested positive for the condition. This figure is particularly significant because it confirms that primary aldosteronism is not merely a rare clinical curiosity but a common, treatable, and currently underdiagnosed cause of high blood pressure.
"We all know primary aldosteronism is a common but underdiagnosed cause of hypertension," Varghese stated during her presentation. "Only 0.76% of eligible adults were screened, so expanding screening may meaningfully improve detection. An 8.7% positive rate in real-world screening is a meaningful yield."
Primary aldosteronism occurs when the adrenal glands produce an excess of aldosterone, a hormone that regulates the balance of salt and water in the body. The resulting hormonal imbalance leads to sodium retention and potassium excretion, which significantly raises blood pressure. Unlike essential hypertension, which is often managed through generic lifestyle changes or broad-spectrum blood pressure medications, PA requires a specialized clinical approach.
A Timeline of Neglect: The Chronology of the Crisis
The challenge of primary aldosteronism is not new, yet it remains one of the most significant "blind spots" in modern cardiology and endocrinology.
The Early Understanding
For decades, primary aldosteronism was thought to be a rare condition, typically associated with severe, resistant hypertension. Clinical textbooks historically framed it as a "surgical" disease, specifically looking for adrenal adenomas (Conn’s syndrome).
The Shift in Diagnostic Criteria
Over the last 15 years, the medical community has shifted its perspective. Advanced diagnostic tools and a better understanding of the endocrine system have revealed that PA is far more prevalent in the general hypertensive population than previously estimated. Despite this, clinical practice has lagged.
The 2011–2023 Observational Window
The study conducted by Varghese utilized the Optum Labs Data Warehouse, covering a 12-year period. By tracking claims and electronic health records, the researchers were able to capture the real-world disconnect between official Endocrine Society guidelines—which advocate for universal screening for all hypertension patients—and the actual delivery of care in community settings.
The 2026 Disclosure
The presentation at ENDO 2026 serves as a "wake-up call" to the medical community. By identifying that nearly 99% of new hypertension patients are being missed by screening protocols, the study provides a clear metric for where the healthcare system is failing to meet international standards.
Supporting Data: The Risks of Inaction
The danger of failing to screen for primary aldosteronism extends far beyond elevated blood pressure numbers. Data from previous studies emphasize that untreated or improperly treated PA acts as a silent driver of cardiovascular morbidity and mortality.
A landmark 2023 study published in Hypertension highlighted the catastrophic outcomes associated with undetected PA. Compared to the general population, patients with primary aldosteronism faced:
- 23% higher risk of all-cause mortality.
- 57% higher risk of cardiovascular disease-related death.
- 85% higher risk of stroke.
Furthermore, untreated patients were found to have more than a two-fold higher mortality risk compared to those whose condition was correctly identified and managed. A 2020 meta-analysis reinforced these findings, reporting a significantly higher 3-year mortality risk for PA patients compared to those suffering from essential hypertension.
These statistics illustrate why the current low screening rate is a public health crisis. By failing to differentiate PA from essential hypertension, providers are missing the chance to prescribe targeted therapies that could potentially save thousands of lives annually.
Official Responses and Clinical Guidance
The Endocrine Society has been consistent in its messaging: every patient with hypertension should be screened for primary aldosteronism. The current diagnostic process is relatively straightforward, involving the measurement of aldosterone and renin levels to determine the aldosterone-to-renin ratio.
The Therapeutic Protocol
When a patient screens positive, the treatment pathway diverges sharply from standard hypertension care:
- Surgical Intervention: For patients with unilateral disease (where only one adrenal gland is overproducing), surgery can be curative.
- Medical Management: For those who are not candidates for surgery or have bilateral disease, specialized medication is required. The guidelines prioritize mineralocorticoid receptor antagonists (MRAs), with spironolactone being the preferred agent due to its proven efficacy, low cost, and wide availability.
- Avoiding Ineffective Drugs: The guidelines specifically advise against the use of epithelial sodium-channel (ENaC) inhibitors as a first-line treatment, emphasizing that appropriate MRA therapy is the gold standard for reducing adverse cardiovascular events.
"The goal is to increase identification of individuals with primary aldosteronism and, by initiating primary aldosteronism-specific medical or surgical therapy, improve blood pressure control and reduce primary aldosteronism-associated adverse cardiovascular events," the society notes.
The Implications: Why Screenings Must Expand
The implications of Varghese’s study are twofold: they highlight the failure of the status quo and provide a roadmap for improvement. By analyzing predictors of a positive screen, the research team identified key patient profiles that should trigger immediate concern for clinicians.
Predictors of a Positive Screen
While the study was retrospective, it identified specific demographic and clinical markers that increased the likelihood of a positive result. Patients presenting with these markers should be considered high-priority candidates for the aldosterone-to-renin ratio test.
Barriers to Implementation
Conversely, the study found that certain factors—such as the use of RAAS inhibitors or the presence of heart failure—were tied to lower odds of a positive screen. This is partly due to the way these medications interfere with biochemical testing, making accurate diagnosis more complex. These clinical "interference" patterns often cause doctors to skip screening entirely rather than adjusting the patient’s medication regimen to allow for an accurate test.
Moving Forward
Varghese acknowledged several limitations to the study, including its observational nature and the fact that nearly half of the screened population had missing laboratory data. This "missing data" problem is perhaps the most telling finding of all—even when doctors order the tests, the fragmented nature of modern healthcare systems often prevents the results from being properly integrated into the patient’s care plan.
The next phase of research must focus on whether risk-based or universal screening protocols actually translate to better long-term patient outcomes. As Varghese concluded, "Future studies are needed to determine whether broader screening improves primary aldosteronism outcomes."
Conclusion: A Call for Clinical Vigilance
The low rate of screening for primary aldosteronism is a systemic failure that has persisted for too long. With 8.7% of screened patients in this real-world cohort testing positive, it is clear that millions of people are currently living with an undiagnosed hormonal condition that is significantly increasing their risk of heart attack, stroke, and early death.
The technology and the guidelines are already in place; what is missing is the clinical momentum. For primary care physicians and cardiologists, the message from ENDO 2026 is clear: hypertension should no longer be treated as a monolithic condition. By expanding screening and committing to the diagnostic protocols established by the Endocrine Society, the medical community can move toward a future where primary aldosteronism is no longer a hidden killer, but a managed, and often curable, clinical reality.
