Duration of adrenal insufficiency after surgical treatment of endogenous hypercortisolism: a prospective cohort study.

OBJECTIVE: Evidence on the duration of post-operative adrenal insufficiency (AI) in patients with endogenous hypercortisolism is scarce. We sought to determine the duration of post-operative 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, 2019-2025, of patients with endogenous hypercortisolism [Cushing syndrome (CS) or mild autonomous cortisol secretion (MACS)] treated with surgery. Associations of demographics, body mass index (BMI), clinical, and biochemical hypercortisolism severity, subtype of hypercortisolism, pre-surgical hypercortisolism duration, glucocorticoid type, and nadir cortisol in relation to duration of AI were investigated. RESULTS: The 242 patients [41% MACS, 46% pituitary CS, 12% adrenal CS, 1% ectopic CS, median age 50 years (IQR: 40-60), 85% women] who developed postsurgical AI were followed for a median duration of 13.7 months (IQR 7.2-26.3). The median time to recovery of AI was shorter in MACS vs. overt CS (3.9 months (95% CI: 3.3-6.2) vs. 13.5 months (95% CI 11.3-18.3), P value < .001). On multivariable analysis adjusting for age, sex, BMI, and glucocorticoid type, moderate to severe biochemical severity score (β = 11, P value < .001) and moderate to severe clinical severity score (β=8.7, P < .001), were associated with a longer duration of AI. CONCLUSIONS: Baseline clinical and biochemical hypercortisolism severity scores may inform individualized counseling on post-operative AI duration in patients treated for CS and MACS.