Association of Kidney Function With Residual Hypertension After Treatment of Aldosterone-Producing Adenoma

Background

Autonomous secretion of aldosterone in patients with primary aldosteronism increases glomerular filtration rate and causes kidney damage. The influence of a mild decrease in kidney function on residual hypertension after adrenalectomy is unexplored.

Study Design

Nonconcurrent prospective study.

Setting & Participants

The study was based on the Taiwan Primary Aldosteronism Investigation (TAIPAI) database. 150 patients (61 men; overall mean age, 47.2 ± 11.6 years) with a diagnosis of aldosterone-producing adenoma had undergone unilateral adrenalectomy at National Taiwan University Hospital from July 1999 to January 2007.

Predictor

Presurgery estimated glomerular filtration rate (eGFR).

Outcomes & Measurements

Residual hypertension after adrenalectomy, defined either as less than 75% of recorded blood pressure measurements with systolic blood pressure less than 140 mm Hg and diastolic blood pressure less than 90 mm Hg or requiring antihypertensive medications during the first year after surgery.

Results

Before surgery, 27 (18%), 72 (48%), and 51 (34%) patients had moderately to severely decreased (<60 mL/min/1.73 m²), mildly decreased (60 ≤ eGFR < 90 mL/min/1.73 m²), or nondecreased eGFR (≥90 mL/min/1.73 m²), respectively. After surgery, 16 (59.3%), 29 (40.3%), and 10 (19.3%) patients in each category had postsurgery residual hypertension. Compared with patients without decreased eGFR before surgery, adjusted odds ratios for postsurgery residual hypertension were 2.7 (95% confidence interval, 1.03 to 7.0; P = 0.04) and 2.8 (95% confidence interval, 1.05 to 9.3) for mildly and moderately to severely decreased eGFR, respectively.

Limitations

Arbitrary definition for residual hypertension.

Conclusions

Two-thirds of patients with aldosterone-producing adenoma were cured of hypertension by means of unilateral adrenalectomy. Kidney function impairment, even mild, appears to be associated with a high incidence of postsurgery residual hypertension.

Index Words: Primary aldosteronism, adrenalectomy, residual hypertension, glomerular filtration rate