Kauffman Robert P, Baker Vicki M, Dimarino Pamela, Gimpel Terry, Castracane V Daniel
Department of Obstetrics and Gynecology, Texas Tech University Health Science Center at Amarillo, 79106, USA.
Am J Obstet Gynecol. 2002 Nov;187(5):1362-9. doi: 10.1067/mob.2002.126650.
We sought to determine what differences, if any, existed between white and Mexican American women with polycystic ovary syndrome (PCOS) and whether the same values for fasting insulin, fasting glucose/insulin ratio, and homeostasis model assessment (HOMA) might be applied when screening both ethnic groups for insulin resistance.
Eighty-three consecutive women suspected to have PCOS but who demonstrated absence of other endocrine disorders comprised the study population. Nineteen healthy ovulatory women volunteered as controls. Fasting serum samples were obtained for determination of thyroid-stimulating hormone (TSH), prolactin, glucose, insulin, free and total testosterone, 17-hydroxyprogesterone, and dehydroepiandrosterone sulfate in the early proliferative phase. An oral glucose load was administered, and blood samples for glucose and insulin were drawn at 1, 2, and 3 hours. Those with impaired glucose tolerance or diabetes mellitus were excluded from our final study population. Four different groups were defined: (1) women with PCOS and insulin resistance, (2) women with PCOS without insulin resistance, (3) women with irregular cycles but without PCOS or another identifiable endocrinopathy, and (4) regular, cycling control subjects. Each group was subdivided by ethnicity (white or Mexican American). A total of 65 white and 37 Mexican American women were studied, including control subjects.
Among all study participants, Mexican American women with PCOS had significantly higher mean values for body mass index, fasting insulin, and HOMA but lower mean fasting glucose/insulin levels than white women. When group 1 patients (PCOS with insulin resistance) were compared between ethnic groups, mean fasting insulin and HOMA levels were significantly lower and glucose/insulin ratios higher in white than in Mexican American women. A single cutoff value for insulin resistance in PCOS was insensitive when applied to both ethnic groups. A fasting insulin value >20 microU/mL, HOMA value > 3.8, and glucose/insulin value <7.2 were reasonable screening values in our population of white women, whereas a fasting insulin value >23 microU/mL, HOMA value >4.5, and glucose/insulin ratio <4.0 were feasible screening values in Mexican American women.
We conclude that (1) Mexican American women with PCOS are more insulin resistant than white women, (2) the incidence of insulin resistance is higher in Mexican American women with PCOS than in white women, (3) a single "screening" value for PCOS-related insulin resistance screening cannot be applied to both white and Mexican American women, and (4) normative values for insulin resistance screening in the PCOS population should be individualized for different racial or ethnic populations.
我们试图确定患有多囊卵巢综合征（PCOS）的白人女性和墨西哥裔美国女性之间是否存在差异，以及在对这两个种族群体进行胰岛素抵抗筛查时，空腹胰岛素、空腹血糖/胰岛素比值和稳态模型评估（HOMA）的相同数值是否适用。
连续83名疑似患有PCOS但无其他内分泌疾病的女性构成了研究人群。19名健康的有排卵女性自愿作为对照。在增殖早期采集空腹血清样本，以测定促甲状腺激素（TSH）、催乳素、葡萄糖、胰岛素、游离睾酮和总睾酮、17-羟孕酮以及硫酸脱氢表雄酮。给予口服葡萄糖负荷，并在1、2和3小时采集血糖和胰岛素血样。糖耐量受损或患有糖尿病的女性被排除在最终研究人群之外。定义了四个不同的组：（1）患有PCOS且有胰岛素抵抗的女性，（2）患有PCOS但无胰岛素抵抗的女性，（3）月经周期不规律但无PCOS或其他可识别内分泌疾病的女性，（4）规律月经周期的对照受试者。每组再按种族（白人或墨西哥裔美国人）细分。共研究了65名白人女性和37名墨西哥裔美国女性，包括对照受试者。
在所有研究参与者中，患有PCOS的墨西哥裔美国女性的体重指数、空腹胰岛素和HOMA的平均值显著高于白人女性，但空腹血糖/胰岛素水平的平均值低于白人女性。当比较第1组患者（患有胰岛素抵抗的PCOS患者）的种族差异时，白人女性的空腹胰岛素和HOMA水平平均值显著低于墨西哥裔美国女性，而血糖/胰岛素比值则更高。PCOS中胰岛素抵抗的单一临界值应用于两个种族群体时并不敏感。空腹胰岛素值>20微单位/毫升、HOMA值>3.8以及血糖/胰岛素值<7.2是我们白人女性人群中合理的筛查值，而空腹胰岛素值>23微单位/毫升、HOMA值>4.5以及血糖/胰岛素比值<
4.0是墨西哥裔美国女性可行的筛查值。
我们得出结论：（1）患有PCOS的墨西哥裔美国女性比白人女性更具胰岛素抵抗性；（2）患有PCOS的墨西哥裔美国女性中胰岛素抵抗的发生率高于白人女性；（3）PCOS相关胰岛素抵抗筛查的单一“筛查”值不能同时应用于白人和墨西哥裔美国女性；（4）PCOS人群中胰岛素抵抗筛查的标准值应针对不同种族或民族群体进行个体化。
