Endocrinology and Metabolic Diseases, Catholic University-Policlinico A. Gemelli, Largo A. Gemelli 8, 00168 Rome, Italy.
Clin Endocrinol (Oxf). 2011 Mar;74(3):300-5. doi: 10.1111/j.1365-2265.2010.03928.x.
Adrenal incidentalomas (AI) have often been associated with a high prevalence of insulin resistance (IR) and cardiovascular risk factors, although direct measurement of insulin sensitivity (IS) has never been carried out.
We aimed to investigate whether the morphological and hormonal features of AI correlate with the presence and severity of IR, using the hyperinsulinaemic euglycaemic clamp (HEC).
Forty patients with AI (22 women) with a mean age of 58.5±11.1 years underwent hormonal and morphological evaluation. Nineteen patients with AI without known history of diabetes mellitus (DM) or impaired glucose tolerance (IGT) and 17 matched controls underwent oral glucose tolerance test (OGTT) and hyperinsulinaemic euglycaemic clamp (HEC).
Diabetes mellitus was observed in 13 patients (33%), while three (8%) had IGT. Thirty-one of the AI were nonfunctioning (82.5%), whereas two (5%) secreted cortisol (Cushing's syndrome) and seven (12.5%) showed subclinical secretion of cortisol. The 19 patients with nonfunctioning AI were more insulin resistant than controls (glucose up-take: 4.58±1.80 vs 5.85±2.48 mg/kg/min respectively; P=0.01); IS was inversely related to the mass size (r=-0.57; P=0.04), free urinary cortisol (r=-0.68; P=0.01), serum cortisol after 1-mg dexamethasone suppression (-0.65; P=0.02) and percentage of trunk fat mass (-0.77; P=0.02) and directly related to serum adreno cortico tropic hormone (ACTH) (r=0.62; P=0.03). After performing multivariate regression, the mass size was found to be the most powerful predictor of IR.
Our study showed a high prevalence of insulin resistance in patients with nonfunctioning AI and suggests its possible involvement in AI growth.
肾上腺意外瘤（AI）常与胰岛素抵抗（IR）和心血管危险因素的高发相关，尽管从未直接测量过胰岛素敏感性（IS）。
我们旨在使用高胰岛素正葡萄糖钳夹（HEC）研究 AI 的形态和激素特征是否与 IR 的存在和严重程度相关。
40 名 AI 患者（22 名女性），平均年龄 58.5±11.1 岁，进行了激素和形态评估。19 名无糖尿病（DM）或糖耐量受损（IGT）病史的 AI 患者和 17 名匹配的对照者进行了口服葡萄糖耐量试验（OGTT）和高胰岛素正葡萄糖钳夹（HEC）。
13 名患者（33%）患有糖尿病，3 名（8%）患有 IGT。31 名 AI 为无功能（82.5%），2 名（5%）分泌皮质醇（库欣综合征），7 名（12.5%）表现为亚临床皮质醇分泌。19 名无功能 AI 患者比对照组更胰岛素抵抗（葡萄糖摄取：分别为 4.58±1.80 和 5.85±2.48mg/kg/min；P=0.01）；IS 与质量大小呈负相关（r=-0.57；P=0.04），与游离尿皮质醇（r=-0.68；P=0.01），1mg 地塞米松抑制后血清皮质醇（r=-0.65；P=0.02）和躯干脂肪质量百分比（r=-0.77；P=0.02）呈负相关，与血清促肾上腺皮质激素（ACTH）呈正相关（r=0.62；P=0.03）。进行多元回归后，发现质量大小是 IR 的最有力预测因素。
我们的研究表明，无功能 AI 患者存在胰岛素抵抗的高患病率，并提示其可能参与 AI 的生长。
