Background. The suppressed hypothalamic-pituitary-adrenal (HPA) axis after successful surgery for Cushing’s disease (CD) will recover in almost all patients. We aimed to identify the predictive factors for HPA axis recovery in CD patients with postoperative remission. Design and Methods. This observational retrospective cross-sectional study enrolled 69 CD patients with postoperative remission in Huashan Hospital from 2015 to 2019. All subjects had a detailed clinical evaluation. The low-dose ACTH stimulation test (LDT) was conducted as the gold standard for assessing the HPA axis function. Results. Peak cortisol in LDT was found only to be positively correlative with morning serum cortisol (MSC) (, ). The MSC was higher (), and the median postoperative course was significantly longer () in the patients with the recovered HPA axis function compared with unrecovered patients. The AUC value of MSC for predicting the recovery of the HPA axis was 0.701, and the optimal cutoff was 6.25 μg/dl (sensitivity 85.19% and specificity 47.62%). Other useful cutoff values were 10.74 μg/dl (specificity 100%) and 4.18 μg/dl (sensitivity 100%). Besides, combined with the postoperative course, the AUC values were higher than MSC alone (0.935 vs. 0.701, ). Conclusions. MSC is a viable first-step diagnostic predictor for HPA axis recovery in CD patients with postoperative remission. For the patients with cortisol levels between 4.18 and 10.74 μg/dl, a confirmatory test should be conducted. When the MSC level was 10.74 μg/dl or greater, the replacement therapy could be discontinued.

中文翻译：

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早晨血清皮质醇作为库欣病 HPA 轴恢复的预测因子

背景。库欣病 (CD) 成功手术后抑制的下丘脑-垂体-肾上腺 (HPA) 轴将在几乎所有患者中恢复。我们旨在确定术后缓解的 CD 患者 HPA 轴恢复的预测因素。设计和方法。这项观察性回顾性横断面研究纳入了华山医院2015年至2019年69例术后缓解的CD患者。所有受试者均进行了详细的临床评估。进行低剂量 ACTH 刺激试验 (LDT) 作为评估 HPA 轴功能的金标准。结果。发现 LDT 中的峰值皮质醇仅与早晨血清皮质醇 (MSC) 呈正相关（, ）。MSC 较高（），术后中位病程明显更长（)与未恢复的患者相比，HPA 轴功能恢复的患者。MSC预测HPA轴恢复的AUC值为0.701，最佳截断值为6.25  μ g/dl（敏感性85.19%，特异性47.62%）。其他有用的截止值是 10.74  μ g/dl（特异性 100%）和 4.18  μ g/dl（敏感性 100%）。此外，结合术后病程，AUC 值高于单独的 MSC（0.935 vs. 0.701，）。 结论。MSC 是术后缓解 CD 患者 HPA 轴恢复的可行的第一步诊断预测因子。对于皮质醇水平在 4.18 和 10.74  μg /dl 之间的患者，应进行确认试验。当 MSC 水平为 10.74  μg /dl 或更高时，可以停止替代治疗。