Renal impairment is closely associated with plasma aldosterone concentration in patients with primary aldosteronism

Objective: Several clinical studies have reported that renal impairments are sometimes observed in patients with primary aldosteronism (PA). We analyzed the prevalence of renal impairments in PA patients and identified parameters that increase the risk for them. Design: This is a retrospective cross-sectional study. We assessed the PA database established by the multicenter Japan PA study (JPAS). Data were also collected from patients with essential hypertension (EHT). Methods: We compared the prevalences of proteinuria and lowered estimated glomerular filtration rate (eGFR) between patients with PA and age, sex, blood pressure and duration of hypertension-matched patients with EHT. We also performed logistic regression analysis to identify parameters that increase the risk for these renal impairments. Results: Among 2366 PA patients, the prevalences of proteinuria and lowered eGFR were 10.3 and 11.6%, respectively. The prevalence of proteinuria was significantly higher in PA patients than matched-EHT patients (16.8 vs 4.4%), whereas there was no significant difference in the prevalence of lowered eGFR (17.2 vs 15.0%). The logistic regression analysis also showed that the plasma aldosterone concentration (PAC) significantly increases the risk of proteinuria and lowered eGFR, independent of other known risk factors. Conclusion: Plasma aldosterone levels are closely associated with renal impairment in patients with PA. This is contrast to our earlier finding that the PAC was not itself linearly associated with cardiovascular events such as stroke or ischemic heart disease. The mechanism underlying the kidney damage in patients with PA may differ from that affecting the cardiovascular system.