P-600: Primary aldosteronism with and without hypertensive urgency : Clinical and biochemical features

Primary Aldosteronism (PA) is commonly considered in the diagnosis of a patient with hypokalemia or difficult to control hypertension. Clinical manifestations of PA are highly variable and serious hypertensive urgencies and emergencies are said to be rare. We performed a retrospective analysis of patients diagnosed with PA to identify clinical or biochemical features that would be predictive of a hypertensive emergency or urgency. Fifty-three patients who were evaluated from 1996 through 2002 at the University of Connecticut Health Center were included in this analysis. Patients included had a confirmed diagnosis of PA including a sodium suppression study and appropriate anatomic localization. They were classified as group I (resistant hypertension) and group II (hypertensive emergency based on the initial presentation or absolute blood pressure). A hypertensive emergency/urgency was defined as persistent BP > 200/100 mmHg or acute target organ damage such as pulmonary edema, cerebrovascular accident / transient ischemic attack, myocardial ischemia/infarction or acute renal failure. A comparison of the biochemical and clinical features in the two groups is shown below. Using a linear regression model to predict Systolic BP and entering age, gender, serum aldosterone, aldosterone:renin ratio and BMI as predictor variables resulted in no significant predictors. No single biochemical or clinical feature was found to be predictive of a presentation as a hypertensive emergency/urgency and all patients with such a presentation need to be screened for primary aldosteronism. (See Table)Clinical and Biochemical Features of 2 Presentations of PA Parameter Group 1 Group 2 P Value Number 32 21 Age, years 58 ± 13 59 ± 16 .76 BMI, kg/m2 30 ± 6 31 ± 8.4 .56 Gender, F:M 15:17 8:13 .52 Potassium, mEq/L 3.6 ± 0.63 3.7 ± 0.63 .8 Creatinine, mg/dL 1.0 ± 0.3 1.2 ± 0.4 .11 Aldosterone, ng/dL 22 ± 7 26 ± 16 .3 Aldosterone (ng/dL): Plasma Renin Activity (ng/mL/h) 11–388 11–289 .66 Systolic Blood Pressure, mmHg 172 ± 28 208 ± 7 .001