Struja Tristan, Briner Leonie, Meier Aline, Kutz Alexander, Mundwiler Esther, Huber Andreas, Mueller Beat, Bernasconi Luca, Schuetz Philipp
Endocr Pract. 2017 Aug;23(8):949-961. doi: 10.4158/EP171861.OR. Epub 2017 Jun 14.
Adrenocorticotrophic hormone (ACTH) stimulation testing is the current standard for assessing primary and secondary adrenal insufficiency (AI). We aimed to investigate the value of basal cortisol level for prediction of AI.
We retrospectively analyzed 804 consecutive patients who had high-dose (250 μg, HDT) or low-dose (1 μg, LDT) ACTH testing as part of their diagnostic work-up. Site-specific cut-off levels for AI were <550 in and <500 nmol/L in HDT and LDT, respectively.
Overall, 70/400 (17.5%) in the LDT group and 118/404 (29.2%) in the HDT group showed an insufficient increase of cortisol and were categorized as AI. The receiver operating characteristic curve analysis showed an overall area under the curve (AUC) for basal cortisol of 0.88, which was comparable in LDT (area under the curve [AUC] 0.88) and HDT (AUC 0.88). If basal cortisol levels were ≥450 nmol/L (n = 234/804, 29.1%), the negative predictive value to rule out AI was 98.7%. If cortisol was ≤100 nmol/L (n = 69/804, 8.6%) the positive predictive value was 93.2% to rule in AI. There was a minimal additional value of the 30-minute cortisol level in HDT as compared to the 60-minute result, as well as for delta values.
Basal cortisol levels ≤100 and ≥450 nmol/L were found in almost half of patients tested for possible AI and had high diagnostic accuracy, abolishing the need for formal ACTH testing. The 30-minute cortisol value in HDT did not increase diagnostic accuracy. These data may help guide clinicians when testing can safely be omitted, thereby reducing expenses and simplifying test protocols.
ACTH = adrenocorticotropic hormone AI = adrenal insufficiency AUC = area under the curve CI = confidence interval HDT = high-dose test HPA axis = hypothalamus-pituitary-adrenal axis ITT = insulin tolerance test LDT = low-dose test NR = normal responders LR+/- = positive/negative likelihood ratio NPV = negative predictive value PPV = positive predictive value.
促肾上腺皮质激素（ACTH）刺激试验是目前评估原发性和继发性肾上腺皮质功能减退（AI）的标准方法。我们旨在研究基础皮质醇水平对AI的预测价值。
我们回顾性分析了804例连续接受高剂量（250μg，HDT）或低剂量（1μg，LDT）ACTH试验作为诊断检查一部分的患者。HDT和LDT中AI的特定部位临界值分别为<550和<500nmol/L。
总体而言，LDT组70/400例（17.5%）和HDT组118/404例（29.2%）皮质醇升高不足，被归类为AI。受试者工作特征曲线分析显示基础皮质醇的曲线下总面积（AUC）为0.88，在LDT（曲线下面积[AUC]0.88）和HDT（AUC 0.88）中相当。如果基础皮质醇水平≥450nmol/L（n = 234/804，29.1%），排除AI的阴性预测值为98.7%。如果皮质醇≤100nmol/L（n = 69/804，8.6%），诊断AI的阳性预测值为93.2%。与60分钟结果相比，HDT中30分钟皮质醇水平以及增量值的附加价值极小。
在几乎一半接受可能AI检测的患者中发现基础皮质醇水平≤100和≥450nmol/L，且诊断准确性高，无需进行正式的ACTH试验。HDT中30分钟皮质醇值并未提高诊断准确性。这些数据可能有助于指导临床医生何时可以安全地省略检测，从而降低费用并简化检测方案。
ACTH = 促肾上腺皮质激素；AI = 肾上腺皮质功能减退；AUC = 曲线下面积；CI = 置信区间；HDT = 高剂量试验；HPA轴 = 下丘脑 - 垂体 - 肾上腺轴；ITT = 胰岛素耐量试验；LDT = 低剂量试验；NR = 正常反应者；LR+/- = 阳性/阴性似然比；NPV = 阴性预测值；PPV = 阳性预测值
