ODP270 Prevalence of Primary Hyperaldosteronism in Patients with Resistant Hypertension - An Outpatient Cross-Sectional Clinic-Based Study

Abstract

Abstract Background Primary hyperaldosteronism is the non-suppressible over secretion of aldosterone caused either by an adenoma or bilateral adrenal hyperplasia. Although its reported prevalence is 8-10% in recent studies, intraindividual variability for aldosterone levels poses diagnostic challenges during the screening of these patients. In this study, we aim to assess the prevalence of primary hyperaldosteronism in patients presenting with drug-resistant hypertension, with or without hypokalemia, at a general endocrinology practice with an emphasis on the variability of renin and aldosterone levels in the screening tests used to detect primary hyperaldosteronism. Method: We included participants presenting at our outpatient clinic from June 2020 until January 2022 with blood pressure>140/90mm Hg despite the use of three antihypertensive medications including a diuretic. The screening tests used were morning (8-9 AM) plasma aldosterone concentration (PAC) and plasma renin (PR) level. Aldosterone was measured using L iquid Chromatography-Tandem Mass Spectrometry assay determined by Mayo Clinic. The screening was considered positive when PAC was>10 ng/dL (277 pmol/l) and PR was <1 ng/ml/hr. The tests were repeated if PAC was between 5-10 ng/dL and PR was between 1-2 ng/ml/hr without any medication changes. If the repeat PR was >2 ng/ml/hr, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers were stopped and changed to calcium channel blockers, and the patient was tested again after 2 weeks. Positive results were further tested with 24-hour urinary aldosterone excretion during high dietary salt ingestion with 24-hour urine sodium and creatinine. Primary hyperaldosteronism was confirmed if plasma renin activity was <1. 0 ng/mL per hour and urinary aldosterone was >12 mcg/24-hour during high urinary sodium excretion (>200 mEq/24-hour). Results We studied a total of 138 patients during this study period. Mean age was 58.7 years and BMI 33.7 kg/m 2, out of which 95 participants had type 2 diabetes mellitus, 7 had obstructive sleep apnea, and 20 had chronic kidney disease stage 3 or higher. We found 3 patients were positive on screening tests and two patients were confirmed to have primary hyperaldosteronism, making prevalence 2/138(1.45%). Conclusion Hyperaldosteronism is the most common cause of secondary hypertension, especially resistant hypertension. Repeat testing of aldosterone levels with intraindividual variability can be very challenging, and time-consuming resulting in repeated follow-up visits and multiple communications with providers posing challenges for effective care coordination, and financial burden on patients. Further large-scale studies are recommended to re-analyze the protocols for screening hyperaldosteronism and treatment initiation without extensive confirmatorytesting. We also suggest health care providers emphasize on effective management of other secondary causes of hypertension such as obesity and Metabolic Syndrome with diabetes for a greater impact on blood pressure control on these patients. Presentation: No date and time listed