SAT-271 Serum steroid profiles in subtyping primary aldosteronism and detecting mild autonomous cortisol secretion

Abstract Disclosure: S. Park: None. J. Noh: None. M. Park: None. M. Choi: None. J. Kim: None. Introduction: Primary aldosteronism (PA), accounting for approximately 5% of all hypertension cases, is categorized into lateralized PA (LPA) and non-lateralized PA (non-LPA) based on the laterality of aldosterone secretion. While treatment strategies differ substantially between subtypes, their differentiation currently requires invasive procedures, such as adrenal venous sampling (AVS). Additionally, although mild autonomous cortisol secretion (MACS) is clinically relevant in PA patients, its detection relies on dynamic hormone tests. This study aimed to identify serum steroid markers for differentiating LPA from non-LPA and detecting MACS in PA patients. Methods: A total of 197 patients with PA (males, n=91) were prospectively enrolled from Seoul National University Hospital between 2007 and 2019 . The laterality of PA was determined based on AVS results. Nineteen serum steroid profiles were conducted by liquid chromatography-mass spectrometry. Logistic regression and receiver operating characteristic (ROC) analysis were performed to identify steroid markers for differentiating the LPA and MACS. Results: The average age was comparable between males (51.3 years) and females (51.4 years). LPA patients showed higher aldosterone and 18-hydroxycortisol (18-OHF) levels compared to non-LPA patients (P < 0.05). In contrast, non-LPA patients demonstrated higher levels of 11-deoxycortisol (11-deoxyF), cortisol (F), tetrahydrocortisol, tetrahydrocortisone, and 11-hydroxyandrostenedione (11-OHA4) (P < 0.05 for all). A conventional predictors for LPA, including body mass index, aldosterone-to-renin ratio, aldosterone, and potassium, achieved an area under the curve (AUC) of 0.73 (95% CI 0.66-0.80). The combination of distinctive three serum steroids, including 18-OHF, 11-deoxyF, and 11-OHA4, showed an AUC of 0.77 (95% CI 0.71-0.84). When conventional predictors were combined with three serum steroids, the AUC significantly improved to 0.81 than conventional predictors alone (P = 0.005). Furthermore, the F/18-OHF ratio demonstrated comparable discriminative performance to the three steroid profiles (AUC = 0.77 vs. 0.76, respectively, P = 0.534). In both PA subtypes, A4 levels were significantly lower in cases with MACS (P < 0.05). For LPA, 18-OHF levels were higher in patients with MACS, whereas for non-LPA, dehydroepiandrosterone sulfate (DHEA-S) levels were lower in cases with MACS. In LPA patients, A4 and 18-OHF predicted MACS with an AUC of 0.70 (95% CI, 0.56-0.85). Conclusion: Serum steroid profiles effectively differentiate LPA from non-LPA and detect MACS in PA patients. Elevated 18-OHF/F ratio can be useful predictor for LPA. In PA, low levels of A4 and DHEA-S, along with high 18-OHF, indicate the presence of MACS. These findings suggest a non-invasive approach to improve PA diagnosis and management. Presentation: Saturday, July 12, 2025