Maes M, Jacobs M P, Suy E, Minner B, Raus J
Psychiatric Centre, St Jozef, Munsterbilizen, Belgium.
Biol Psychiatry. 1990 Aug 15;28(4):349-57. doi: 10.1016/0006-3223(90)90662-l.
This study investigates the relationships between cortisol escape from suppression by dexamethasone during a depressive episode, and the baseline activity of the hypothalamic-pituitary-adrenal (HPA) axis, circulating dexamethasone levels, and age. To this end, we measured urinary-free cortisol (UFC) excretion in 24-hr urine samples and the 8 AM cortisol and dexamethasone levels after administration of 1 mg dexamethasone in 50 depressive patients. We found that up to 54% of the variance in the postdexamethasone cortisol values could be explained by the multiple regression on UFC, age, and dexamethasone levels. By utilizing these three parameters, the dexamethasone suppression test (DST) nonsuppressor/suppressor state was correctly identified in 92% of the subjects. It was shown that an important part of the variance in postdexamethasone cortisol is actually background variance, irrelevant to depression and produced by the cumulative effects of the three aforementioned parameters. Only a small part (less than 20%) of the variance in postdexamethasone cortisol is determined by the actual depressive state. It was concluded that (1) baseline hypersecretion of cortisol, (2) decrements in the bioavailability of the test substance, (3) increasing age, and (4) the depressive state per se--all of which are cumulative--contribute independently to cortisol escape from suppression by 1 mg dexamethasone.
本研究调查了抑郁发作期间皮质醇对地塞米松抑制的逃脱与下丘脑 - 垂体 - 肾上腺（HPA）轴的基础活性、循环地塞米松水平和年龄之间的关系。为此，我们测量了50名抑郁症患者24小时尿液样本中的尿游离皮质醇（UFC）排泄量以及给予1毫克地塞米松后上午8点的皮质醇和地塞米松水平。我们发现，地塞米松后皮质醇值高达54%的变异可以通过对UFC、年龄和地塞米松水平的多元回归来解释。利用这三个参数，在92%的受试者中正确识别了地塞米松抑制试验（DST）的非抑制/抑制状态。结果表明，地塞米松后皮质醇变异的一个重要部分实际上是背景变异，与抑郁症无关，由上述三个参数的累积效应产生。地塞米松后皮质醇变异中只有一小部分（不到20%）由实际抑郁状态决定。研究得出结论：（1）皮质醇的基础分泌过多，（2）测试物质生物利用度的降低，（3）年龄增长，以及（4）抑郁状态本身——所有这些都是累积性的——均独立导致皮质醇逃脱1毫克地塞米松的抑制。
