Abstract 135: Activated Intrarenal Renin Angiotensin System Contributes to the Development of Chronic Kidney Disease in Primary Aldosteronism

Abstract

Background: Patients with primary aldosteronism (PA) have higher prevalence of albuminuria than those with essential hypertension (EH). We have shown that about 15% in PA patients had chronic kidney disease (CKD). Hence, the active screening of PA is important to prevent CKD. Urinary angiotensinogen (UAGT) has been reported as the earliest predictor of nephropathy in patients with type 1 diabetes (DM). UAGT indicates the intrarenal renin angiotensin systems (RAS) activation which plays an important role in the development of CKD. This study aimed to confirm the existence of activated intrarenal RAS by measuring UAGT in patients with PA. Methods: Consecutive 58 patients of aldosteronoma (APA) participated. No patients had CKD defined as eGFR <60 ml/min/1.73m 2 or urinary albumin (UA) ≥30 mg/g cre and DM defined as HbA1c ≥6.5% or taking treatments. As control subjects, 59 EH patients were included. All APA patients were treated by sufficient dose of mineralocorticoid receptor (MR) antagonists (MRA) until the day of adrenalectomy. Urine samples were collected on 10g salt diet between baseline and after MRA treatment. UAGT (ng/g cre) was measured and the value was transformed by logarithm. Results: Age, sex distribution, blood pressure, duration of hypertension, eGFR, and UA were similar between two groups at baseline. However, UAGT was significantly higher in APA than in EH (Fig). In multivariate analysis, only plasma aldosterone was significantly related with UAGT in APA (t=3.572, p=0.0007). UAGT was significantly decreased after MRA treatment (Fig). Conclusion: Intrarenal RAS is activated by aldosterone/MR in patients of PA, which might contribute to the development of CKD.