Brophy T, Chalk J B, Ridgeway K, Tyrer J H, Eadie M J
J Neurol Neurosurg Psychiatry. 1984 Oct;47(10):1081-6. doi: 10.1136/jnnp.47.10.1081.
Simultaneous plasma dexamethasone and cortisol levels were followed at intervals over 8 hour periods on 40 occasions in 19 subjects who received regular high dosage dexamethasone therapy (rarely less than 12 mg a day) for various neurological and neurosurgical conditions. Lower dexamethasone doses (for example 2 mg daily for 2 days) normally suppress adrenal cortical production of cortisol to below 50 micrograms/l for at least 8 hours. However, in 12 of the 35 studies that did not take place at the first steroid dose or in subjects taking second daily bolus steroid dosage such suppression was not present 8 to 12 hours after dexamethasone intake, though it was shown that dexamethasone could suppress cortisol production in all these cases. Failure of maintained suppression despite the high steroid dose appeared to be related to rapid elimination of dexamethasone. These findings may help explain the relative rarity of adrenal failure in clinical neurological practice after high dosage steroid therapy is ceased.
对19名因各种神经和神经外科疾病接受常规高剂量地塞米松治疗（每日剂量很少低于12毫克）的患者，在40个不同时段，每隔8小时同时监测血浆地塞米松和皮质醇水平。较低剂量的地塞米松（例如，连续2天每日2毫克）通常会使肾上腺皮质分泌的皮质醇在至少8小时内降至50微克/升以下。然而，在35项研究中，有12项不是在首次使用类固醇剂量时进行的，或者是在接受每日第二次大剂量类固醇给药的患者中，地塞米松摄入后8至12小时未出现这种抑制作用，尽管结果表明在所有这些情况下地塞米松都能抑制皮质醇的分泌。尽管类固醇剂量很高，但持续抑制失败似乎与地塞米松的快速清除有关。这些发现可能有助于解释在停止高剂量类固醇治疗后，临床神经实践中肾上腺功能衰竭相对少见的原因。
