Age-Dependent Progression of Renal Dysfunction After Adrenalectomy for Aldosterone-Producing Adenomas in Japan

CONTEXT: In patients with aldosterone-producing adenomas (APAs), adrenalectomy causes a rapid decrease in blood pressure and increase in blood potassium levels; however, the effects of these intensive metabolic changes on kidney function with age have not yet been examined in Japan. OBJECTIVE: To investigate factors related to the progression of kidney dysfunction after adrenalectomy in different age groups. PARTICIPANTS: Fifty Japanese patients with APAs and 27,572 health checkup patients as controls were examined. MAIN OUTCOME MEASURES: We investigated changes in estimated glomerular filtration rate (eGFR) after adrenalectomy and characterized patients who progressed to chronic kidney disease (CKD). RESULTS: The postoperative cutoff age of CKD is 50 years and age is a unique factor for the progression of CKD after adrenalectomy. Among preoperative patients, CKD was 6% for those <50 years old and 40% for those ≥50 years old, indicating a higher prevalence of CKD with APAs than in control subjects. Median eGFR <50 mL/min/1.73 m(2) did not significantly change after adrenalectomy but decreased from 67 to 42 mL/min/1.73 m(2) in those with APAs ≥50 years old. Patients with APAs ≥50 years old who progressed to CKD showed higher preoperative aldosterone/renin ratios, lower potassium and chloride levels, lower body mass index, and a higher incidence of a history of cardiovascular events and KCNJ5 mutation rates. CONCLUSION: Age is the most important predictor of the progression of kidney dysfunction after adrenalectomy in Japanese patients with APAs, particularly those with a history of cardiovascular events and positivity for KCNJ5 mutations.