Association between acute fall in estimated glomerular filtration rate after treatment for primary aldosteronism and long-term decline in renal function

Primary aldosteronism causes renal structural damage after glomerular hyperfiltration, and primary aldosteronism-specific treatment leads to an acute fall in estimated glomerular filtration rate (eGFR). We investigated whether this change affected the long-term eGFR slope in a retrospective cohort from the multicenter Japan Primary Aldosteronism Study. We allocated patients with primary aldosteronism to the adrenalectomy (n=202) and MR (mineralocorticoid receptor) antagonist (n=303) groups based on their treatment history and analyzed the association between the initial eGFR fall and long-term eGFR slope. The increased age, low serum potassium levels, high eGFR, and high plasma aldosterone levels were independent predictors for a large initial eGFR fall in both groups. Our analysis of tertiles based on the initial eGFR fall revealed that in the MR antagonist group, patients with a small initial eGFR fall had a significantly steeper long-term eGFR slope than those with a large initial fall (tertile 1 versus 2, P=0.025; tertile 1 versus 3, P=0.017). These associations were not identified in the adrenalectomy group. Thus, the smaller the acute fall in eGFR by initiation of MR antagonists, the greater was the rate of long-term eGFR decline. While the acute fall in eGFR induced by primary aldosteronism-specific treatment is occasionally a clinical concern, our findings highlight the favorable implications of the acute fall with respect to long-term renal outcomes.