Predictors of decreasing glomerular filtration rate and prevalence of chronic kidney disease after treatment of primary aldosteronism: renal outcome of 213 cases.

CONTEXT: In primary aldosteronism (PA), glomerular hyperfiltration due to excessive aldosterone is considered to underestimate actual renal damage.
OBJECTIVE: Our objectives were to determine the prevalence of chronic kidney disease (CKD) in PA and identify the predictors of decreasing estimated glomerular filtration rate (eGFR) after treatment. DESIGN AND
SETTING: This was a 12-month prospective study of patients with PA treated at Tohoku University Hospital. PATIENTS AND
INTERVENTIONS: All patients were treated according to the results of adrenal venous sampling; 102 patients with aldosterone-producing adenoma underwent adrenalectomy, and 111 with bilateral hyperaldosteronism were treated with mineralocorticoid receptor antagonists. MAIN OUTCOME MEASURES: Electrolytes, blood pressure, and indicators of renal function were determined at 1 and 12 months after intervention.
RESULTS: Blood pressure, urinary albumin excretion (UAE), and eGFR, which significantly decreased at 1 month after treatment of PA, did not further decrease at 12 months. Prevalence of CKD, which was 15.7% in aldosterone-producing adenoma and 8.1% in bilateral hyperaldosteronism at the first visit, increased to 37.1% and 28.3%, respectively, at the end of study (P < .0001). Multivariate regression analysis revealed that higher UAE and lower serum potassium levels were found to be independent predictors of decreasing eGFR after intervention.
CONCLUSIONS: This large cohort study shows that the prevalence of CKD in PA was increased after treatment and that higher UAE and lower serum potassium levels at the first visit were predictors of decreasing eGFR after treatment of PA. To prevent a large decrease of eGFR after intervention, PA patients should be diagnosed before evolution to severe albuminuria and hypokalemia.