How do you evaluate the curative score in an adult patient with primary aldosteronism (PA) after unilateral adrenalectomy or bilateral adrenal vein sampling?

Evaluating Curative Outcomes After Surgery for Primary Aldosteronism

Use the Primary Aldosteronism Surgical Outcome (PASO) score to predict clinical cure after unilateral adrenalectomy, which incorporates six presurgical factors and achieves 79% accuracy in predicting complete clinical success. 1

The PASO Score System

The PASO score is a validated 25-point predictive tool that stratifies patients based on likelihood of complete clinical success (resolution of hypertension without antihypertensive medications) versus partial success (improved blood pressure control with fewer medications). 1

Six Key Predictive Factors

The score incorporates the following presurgical variables, each weighted based on their association with complete clinical success: 1

• Duration of hypertension - Shorter duration predicts better outcomes 1
• Sex - Female sex is associated with higher cure rates; male sex predicts persistent hypertension 2
• Number and dosage of antihypertensive medications - Fewer medications predict better outcomes 1
• Body mass index - Lower BMI associated with higher cure rates 1, 2
• Target organ damage - Absence of left ventricular hypertrophy (LVH) predicts cure; presence of LVH predicts persistent hypertension 1, 2
• Size of largest adrenal nodule on imaging - Larger nodules may predict better outcomes 1

Score Interpretation

• PASO score >16 points: High likelihood of complete clinical success (cure of hypertension without medications) with 84.4% specificity and 71.3% sensitivity 1
• PASO score ≤16 points: Patient will likely require continued surveillance and antihypertensive medications despite biochemical cure 1
• The score achieves an area under the curve of 0.839, indicating excellent discriminatory ability 1

Expected Outcomes After Unilateral Adrenalectomy

Biochemical Success

• 95-99% of patients achieve biochemical cure (resolution of autonomous aldosterone secretion and hypokalemia) 3, 4
• All patients are cured of hypokalemia 5
• Biochemical resolution normalizes the aldosterone-renin ratio and suppresses autonomous aldosterone production 2

Clinical Success Rates

Complete clinical success (cure of hypertension without medications) occurs in approximately 38-50% of patients, with significant variability between centers. 3, 5, 1, 2 This wide range reflects differences in patient selection, duration of hypertension before surgery, and presence of target organ damage.

Partial clinical success (improved blood pressure control with fewer medications) occurs in an additional 47-59% of patients. 5, 2, 4 These patients experience meaningful reduction in antihypertensive medication burden (mean reduction from 2.3 to 0.6 medications). 5

Age-Related Outcomes

Younger patients have significantly better cure rates: 5, 2

• Mean age of cured patients: 44 years 5
• Mean age of patients with persistent hypertension: 55 years 5
• Older patients more likely to have irreversible vascular remodeling from prolonged hypertension exposure 2

Predictors of Persistent Hypertension

On multivariate analysis, the strongest independent predictors of requiring continued antihypertensive therapy after surgery are: 2

• Male sex - Most powerful predictor of persistent hypertension 2
• Higher preoperative systolic blood pressure - Indicates more severe vascular disease 2
• Elevated creatinine - Suggests chronic kidney damage 2
• Presence of left ventricular hypertrophy - Indicates irreversible cardiac remodeling 2
• Increased weight/obesity - Associated with lower cure rates 2

Practical Application Using the PASO Predictor

An online calculator (Primary Aldosteronism Surgical Outcome predictor) is available to facilitate clinical use of the predictive score. 1 This tool allows real-time calculation during preoperative counseling to set realistic patient expectations.

Clinical Decision-Making

• Patients with PASO score >16: Counsel that they have high likelihood of complete cure and can anticipate discontinuing all antihypertensive medications 1
• Patients with PASO score ≤16: Counsel that surgery will cure biochemical disease and improve blood pressure control, but they should expect to require some ongoing antihypertensive therapy, albeit at reduced doses 1

Comparison to Medical Therapy Outcomes

While both surgical and medical management effectively control blood pressure and reverse target organ damage, surgery offers distinct advantages: 3

• Surgical patients require significantly shorter follow-up (mean 6.5 months vs 13.4 months for medical therapy) 6
• Surgical patients can be discharged to community care more quickly after achieving target blood pressure <140/90 mmHg 6
• Medical therapy requires lifelong medication adherence and monitoring for side effects (gynecomastia with spironolactone, hyperkalemia risk) 3, 7

Common Pitfalls in Outcome Assessment

• Do not equate biochemical cure with clinical cure - Nearly all patients achieve biochemical resolution, but only 38-50% achieve complete clinical success 1, 2, 4
• Avoid promising hypertension cure to all patients - Set realistic expectations based on PASO score and presence of target organ damage 1
• Do not delay surgery in younger patients - Earlier intervention before irreversible vascular remodeling improves cure rates 5, 2
• Recognize that "improvement" is still a successful outcome - Patients with partial clinical success have meaningful reduction in medication burden and cardiovascular risk 5, 2