Incidence and factors of post-adrenalectomy hyperkalemia in patients with aldosterone producing adenoma.

BACKGROUND

Hyperkalemia is a potentially serious complication following adrenalectomy of aldosterone-producing adenomas (APA). We analyzed the incidence and risk factors for hyperkalemia after adrenalectomy in patients with APA.

METHODS

We retrospectively analyzed the records of 55 patients who underwent adrenalectomy for APA between 2002 and 2011. Demographic features, biochemical and hormonal profiles, imaging, and relevant medications were reviewed.

RESULTS

Sixteen of 55 APA patients (29.1%) developed hyperkalemia (mean serum K(+) 5.6±0.3 mmol/l) after adrenalectomy and 3 had persistent hyperkalemia requiring mineralocorticoid supplementation for more than nine months. Compared with normokalemic patients, hyperkalemic patients were characterized by male predominance, older age, longer duration of hypertension (12.8±9.3 vs. 6.7±5.0 y, p<0.05), lower nadir serum K(+) (p<0.05), higher preoperative serum creatinine (p<0.01), and higher likelihood of residual hypertension. Using multivariate regression analysis, longer duration of hypertension and impaired renal function were the most important factors of post-adrenalectomy hyperkalemia.

CONCLUSIONS

Post-adrenalectomy hyperkalemia in patients with APA is not rare and associated with impaired renal function and longer duration of hypertension. Serum K(+) must be cautiously monitored in patients with long-term hypertension and kidney disease.