Persistent hypertension after adrenalectomy for an aldosterone-producing adenoma: weight as a critical prognostic factor for aldosterone's lasting effect on the cardiac and vascular systems

Abstract

Background: Primary aldosteronism caused by an aldosterone producing adrenal tumor/aldosteronoma (APA), is a potentially curable form of hypertension, via unilateral adrenalectomy. Resolution of hypertension (HTN) is not as prevalent after tumor resection, as are the normalization of aldosterone secretion, hypokalemia, and other metabolic abnormalities. Here, we review the immediate and long-term medical outcomes of laparoscopic adrenalectomy in patients with an APA, and attempt to identify any distinctive sex differences in the management of resistant HTN.

Methods: We performed a retrospective review of the prospective adrenal database at the University of Wisconsin between January 2001 and October 2010. Of the 165 adrenalectomies performed, 32 were for the resection of an APA. Patients were grouped according to their postoperative HTN status. Those patients with normal blood pressure (≤120/80 mm Hg) and on no antihypertensive medication (CURE) were compared with those who continued to require medication for blood pressure control (HTN). We evaluated sex, age, body mass index, tumor size, duration of time with high blood pressure, and the differences in systolic and diastolic blood pressure following adrenalectomy. Statistical analysis was performed using Student's t-test. Statistical significance was defined as a P value of <0.05.

Results: We identified 32 patients with an APA based on biochemical and radiographic studies, two patients were excluded, due to missing data. There were 19 males (63%) and 11 (37%) females, with a mean age was 48.3 ± 2.1 y, and mean tumor size was 24 ± 3 mm. Postoperatively, patients required significantly fewer antihypertensive medications (1.5 ± 0.2 versus 3.3 ± 0.3, P < 0.001). Nine patients (31%) had complete resolution of their HTN, requiring no postoperative antihypertensive medication. The only significant difference between the sexes, was a lower body mass index in women (27.6 ± 1.7 versus 33.4 ± 2.1 kg/m(2), P = 0.04). Ninety percent of the cohort had at least a 20 mm Hg decline in their systolic blood pressure postoperatively, placing them in the prehypertensive or normal blood pressure categories. Sixty-six percent of the CURE patients required at least 6 mo for resolution of their HTN. All 20 patients who presented with hypokalemia, had immediate resolution postoperatively and did not require continuance of the preoperative spironolactone or potassium supplementation.

Conclusions: Laparoscopic adrenalectomy for aldosterone producing adenoma results in the normalization of, or more readily manageable blood pressure in 90% of patients, within 6 mo. Metabolic disturbances are immediately corrected with tumor resection. Weight is an important contributing factor in resolving HTN.

Figure 1

Prescribed anti-hypertensive medications before and after adrenalectomy for an APA

Figure 2

Gender difference in prescribed anti-hypertensive medications

Figure 3

Pre- and post-operative blood pressure differences between genders

Figure 4

Pre- and post-operative blood pressure changes in CURE and HTN (pre-HTN and PERSISTENT) patients