Aldosterone level after saline infusion test could predict clinical outcome in primary aldosteronism after adrenalectomy

Abstract

Background: The saline infusion test is widely used as a confirmatory test for primary aldosteronism, and we hypothesized that post-saline-infusion test aldosterone levels might predict the clinical outcomes in primary aldosteronism patients after adrenalectomy.

Methods: An observational cohort study was performed. We included primary aldosteronism patients who had undergone adrenalectomy from the Taiwan Primary Aldosteronism Investigation database between 1995 and 2017. The patients were divided into the following 2 groups: the clinical success group and the resist hypertension group, according to the criteria from the Primary Aldosteronism Surgery Outcome consensus.

Results: We enrolled 236 patients with primary aldosteronism (male, 41.1%; mean age, 49.8 years). A total of 79.7% patients achieved clinical success after adrenalectomy after 12-month follow-up. The clinical success group had higher mean blood pressure, higher aldosterone-to-renin ratio, lower potassium, and lower renin levels than that of the resist hypertension group. In multivariate logistic regression analysis, post saline-infusion test aldosterone levels higher than 48 ng/dL (odds ratio, 2.51; 95% confidence interval, 1.04-6.06; P = .040), body mass index less than 25 kg/m² (odds ratio, 2.22; 95% confidence interval, 1.12-4.40; P = .023) and mean blood pressure higher than 115 mmHg (odds ratio, 2.79; 95% confidence interval, 1.37-5.68; P = .005) could predict better clinical success rates after adrenalectomy in primary aldosteronism patients.

Conclusion: Our study demonstrated that the post-saline-infusion test aldosterone level could not only confirm primary aldosteronism but also forecast clinical outcomes in primary aldosteronism patients after adrenalectomy.