The blood pressure response to unilateral adrenalectomy in primary aldosteronism

The factors determining the outcome of blood pressure after removal of the aldosterone-secreting adenoma in primary aldosteronism are largely unknown. We have studied the results of surgery in 21 patients with this disorder, all of whom were investigated and treated in a single referral centre, and evaluated the contributions of clinical, biochemical and pathological factors to blood pressure outcome. Blood pressure before surgery was high (mean 210/121 mmHg), but after an average period of 5.4 years 12 patients (60 per cent) were considered by their primary physician not to require antihypertensive medication and a further seven had reduced drug requirements. In only two patients was arterial pressure unimproved by surgery. Blood pressure recordings within six months of surgery were not a good predictor of later levels. Of the clinical, electrolyte, hormone and pathological features assessed, only the systolic pressure before surgery, and abnormalities in the optic fundi, correlated statistically with final blood pressure ranking. There was no relationship between the severity of vascular changes in the adrenal or kidney biopsy tissue and final blood pressure. These results show that while the blood pressure response to the removal of a single adrenal adenoma is usually good, it is not possible to predict accurately the final blood pressure response using these criteria.