SUN-061 Recovery of Adrenal Insufficiency After Surgical Remission of Endogenous Hypercortisolism: A Prospective Cohort Study

Abstract Disclosure: S.R. Chacko: None. J. Saini: None. S. Sharma Sharma: None. S. Ahmadian: None. S.J. Achenbach: None. E. Atkinson: None. V. Fell: None. J.J. Van Gompel: None. W.F. Young, Jr.: None. I. Bancos: None. Context: Evidence on the duration of postoperative adrenal insufficiency (AI) in patients with endogenous hypercortisolism is scarce. Objective: To determine the duration of postoperative AI and to identify factors associated with the duration of AI in patients undergoing surgery for endogenous hypercortisolism.Methods: We conducted a single center prospective cohort study, 2019-2024, of patients with endogenous hypercortisolism [Cushing syndrome (CS) or mild autonomous cortisol secretion (MACS)] treated with surgery. Associations of demographics, BMI, clinical and biochemical hypercortisolism severity, subtype of hypercortisolism, presurgical hypercortisolism duration and glucocorticoid type in relation to duration of AI were investigated. Results: The 110 patients [36% MACS, 46% pituitary CS, 15% adrenal CS, 3% ectopic CS, median age 50 years (IQR: 40-60), 82% women] who developed postsurgical AI were followed for a median duration of 26 months (IQR: 15-38). By the end of follow up, 96 patients (87%) had recovery of AI. The median time to recovery of AI was shorter in MACS vs. Overt Cushing syndrome (3.0 months (95% CI: 2.5-6.2) vs. 12.3 months (95% CI 9.0-17.3), P =0.002). Biochemical severity score (r=0.32, P=0.002) and duration of preoperative hypercortisolism symptoms (r=0.29, P=0.005), but not age, sex, BMI, clinical severity, or glucocorticoid type were associated with the duration of AI. We found no differences in the duration of AI between patients with ACTH-dependent vs ACTH-independent CS (12.3 months (95% CI: 6.0-17.2) vs 13.9 months (95% CI: 9.0-25.5), P =0.7).Conclusion: In this interim analysis, we showed that after surgical remission of endogenous hypercortisolism, duration of postoperative AI was longer in CS compared to MACS. Additionally, higher biochemical hypercortisolism severity score and a longer duration of symptoms suggestive of hypercortisolism were associated with a longer duration of postoperative AI. Presentation: Sunday, July 13, 2025