Endocrine Abstracts

Background: Primary hyperaldosteronism is a common cause of secondary hypertension, accounting for up to 5% of cases locally. It is treated medically with spironolactone and/or amiloride, or surgically with adrenalectomy. This study determines the prognostic factors for response to treatment, resulting in reduction of blood pressure to normotensive levels.

Methods: We retrospectively reviewed records of 57 patients who were diagnosed with primary hyperaldosteronism by a saline suppression test, and subsequently underwent treatment. The patients were divided into two groups – hypertensive and normotensive (WHO <140/90), based on their blood pressure readings at 1 year since starting treatment. We collected baseline characteristics of both groups, including patient demographics – age, gender, race, BMI, as well as medical comorbidities, use of anti-hypertensive medications, and results of screening and diagnostic tests, and compared them via multivariate analysis.

Results: At 1 year post treatment, 28 (49.1%) patients were normotensive, and 29 (50.9%) were hypertensive. We found that the hypertensive group had more person-years of diabetes (mean=2.52 vs 0.41, P<0.05), and also had a higher baseline aldosterone level (mean=749.15 vs 532.61, P<0.05), than the normotensive group. Other factors, including the patient age, gender, race, BMI, baseline blood pressure, years of hypertension, number and type of antihypertensive medications, baseline creatinine, potassium, sodium, renin, saline suppression test results, treatment type, presence of adenoma on CT scan, did not differ significantly between the two groups.

Discussion and conclusion: In patients diagnosed with primary hyperaldosteronism, predictors for achieving normotension with treatment include not having or having fewer years of diabetes, and having a lower baseline aldosterone level. This knowledge is helpful for physicians to prognosticate response to treatment in newly diagnosed patients.