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Chang, Alice Y.

https://orcid.org/0000-0001-7108-0499

Mayo Clinic

Mayo Clinic

Citations 25

Diagnostic Thresholds for Androgen-Producing Tumors or Pathologic Hyperandrogenism in Women by Use of Total Testosterone Concentrations Measured by Liquid Chromatography-Tandem Mass Spectrometry
Sharma, Anu , Kapoor, Ekta , Chang, Alice Y. , Erickson, Dana , Singh, Ravinder

Clinical Chemistry | August 1, 2018 | Volume: 64 | Issue: 11 | Pages: 1636-1645

10.1373/clinchem.2018.290825 Get It

Abstract BACKGROUND Previously defined thresholds for total testosterone (TT) concentrations to screen for androgen-producing tumors (APTs) have used RIA, which can be less accurate in women. We aimed to define diagnostic thresholds to screen for APTs or postmenopausal pathologic hyperandrogenism using TT concentrations measured by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). METHODS We performed a retrospective cohort study on all women with TT ≥3.5 nmol/L and all postmenopausal women presenting with hyperandrogenism between 2004 and 2014 at the Mayo Clinic in Rochester, MN. RESULTS Of the 369 women with TT ≥3.5 nmol/L, 89 were included and subdivided into 3 groups based on their clinical diagnosis [21 (24%), APT; 16 (18%), postmenopausal pathologic hyperandrogenism; 52 (58%), polycystic ovary syndrome]. The source of the APT was more frequently ovarian (81%, n = 17) than adrenal (19%, n = 4). The diagnostic threshold using ROC analysis for TT to identify APT in women with severe biochemical hyperandrogenemia was ≥5.1 nmol/L (sensitivity, 90%; specificity, 81%). In a second analysis of a cohort of postmenopausal women only presenting with symptoms or signs of hyperandrogenism, median TT was significantly higher in the postmenopausal pathologic hyperandrogenism group (APT and ovarian hyperthecosis) vs the idiopathic hyperandrogenism group (4.9 vs 0.8 nmol/L; P < 0.01). In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was TT ≥2.2 nmol/L (sensitivity, 100%; specificity, 86%). CONCLUSIONS The diagnostic threshold for TT concentration as measured by LC-MS/MS to identify APT in women with biochemical severe hyperandrogenemia was TT ≥5.1 nmol/L. In postmenopausal women, the diagnostic threshold for pathologic hyperandrogenism was lower (TT ≥2.2 nmol/L).
Influence of race/ethnicity on cardiovascular risk factors in polycystic ovary syndrome, the Dallas Heart Study
Chang, Alice Y. , Oshiro, June , Ayers, Colby , Auchus, Richard J. , Oshiro, June

Clinical Endocrinology | November 26, 2015 | Volume: 85 | Issue: 1 | Pages: 92-99

10.1111/cen.12986 Get It

SummaryObjectivePolycystic ovarian syndrome (PCOS) is estimated to affect up to 20% of women. PCOS is associated with insulin resistance and cardiovascular (CV) risk factors. We aimed to evaluate the impact of race/ethnicity on the prevalence of CV risk factors and subclinical predictors of CV events.DesignCross‐sectional analysis of data collected by the Dallas Heart Study, an urban, population‐based cohort oversampled for blacks.PatientsA previously described cohort of women with PCOS and control subjects of the same racial/ethnic group, matched for age and body mass index.MeasurementsHormonal and clinical measures associated with PCOS and CV risk factors.ResultsThe study included 117 women with PCOS and 204 controls. Women with PCOS had significant differences across racial/ethnic groups in the prevalence of hypertension, hypercholesterolaemia, hypertriglyceridaemia and impaired fasting glucose (P < 0·05). Controls showed significant racial/ethnic differences in the prevalence of hypertension and impaired fasting glucose (P < 0·05). The odds of hypertension were significantly greater among women with PCOS than controls after adjusting for race/ethnicity (odds ratio, 1·50 [95% CI, 1·03–2·30]; P = 0·04). However, we did not see an interaction of race/ethnicity that significantly changed CV risk factor prevalence between PCOS and controls. In addition, subclinical measures of CV disease were not different between women with PCOS vs controls, even among hypertensive women.ConclusionsRace/ethnicity affects the prevalence of CV risk factors for women with and without PCOS. However, race/ethnicity does not interact with PCOS to additionally increase CV risk factor prevalence or subclinical CV disease.
Characteristics of Dynamic Magnetic Resonance Image Enhancement in Prolactinomas Resistant to Dopamine Agonist Therapy
Guo, Qinghua , Chang, Alice Y. , Erickson, Dana , Erickson, Bradley J.

Journal of Investigative Medicine | October 16, 2015 | Volume: 63 | Issue: 3 | Pages: 529-533

10.1097/jim.0000000000000138 Get It

Objective The objective of this study was to determine whether dynamic magnetic resonance imaging (dMRI) enhancement parameters could predict dopamine agonist (DA) resistance in prolactinomas. Methods We retrospectively identified patients with prolactinomas who were treated with DA and underwent dMRI from 2001 through 2012 at Mayo Clinic (Rochester, MN). Intensities of the adenoma and pituitary gland were measured by drawing regions of interest on the images. Enhancement ratio, enhancement peak, prepeak slope (PPS), and enhancement time were compared between DA-resistant and DA-responsive groups, between DA-treated and DA-naive groups, and between the first and follow-up dMRIs. Results We identified 49 patients with prolactinomas, with 6 (12.2%) showing DA resistance. Thirty-seven patients (75.5%) underwent dMRI while receiving treatment, 12 (25.5%) underwent dMRI before starting therapy, and 10 (20.4%) had follow-up dMRI after DA therapy. The PPS of the tumor was higher in the treatment-resistant group versus the responsive group (mean [SD], 4.42 [3.19] vs 2.65 [1.59]; P = 0.03), whereas no difference was noted in the pituitary gland (5.79 [2.21] vs 4.06 [2.48]; P = 0.11). Logistic regression analysis indicated that tumor PPS was associated with DA resistance (odds ratio, 1.71; 95% confidence interval, 1.07–3.27; P = 0.02). Conclusions Dynamic MRI with PPS analysis potentially can be used early in the treatment course to evaluate DA resistance in pituitary prolactinomas.
Coronary Endothelial Dysfunction in Women with Type 2 Diabetes Measured by Coronary Phase Contrast Flow Velocity Magnetic Resonance Imaging
Maroules, Christopher D. , Chang, Alice Y. , Kotys-Traughber, Melanie, Peshock, Ronald M.

Journal of Investigative Medicine | October 16, 2015 | Volume: 63 | Issue: 7 | Pages: 856-861

10.1097/jim.0000000000000226 Get It

Objective The aim of this study was to determine if differences in coronary endothelial function are observed between asymptomatic women with type 2 diabetes mellitus (DM) and control subjects using coronary phase contrast flow velocity magnetic resonance imaging in response to cold pressor stress, an established endothelium-dependent vasodilatory stress. Methods Phase contrast flow velocity imaging of the right coronary artery was performed in 7 asymptomatic premenopausal women with DM and 8 healthy female participants in response to the cold pressor test at 3 T. Results There was no significant difference in percent increase in coronary flow velocity from rest to peak flow velocity between DM and control subjects (32% ± 22% vs 46% ± 17%; P = 0.11). However, percent increase in coronary flow velocity was lower in DM than in control subjects (−3% ± 14% vs 31% ± 30%; P = 0.01) during the second minute of cold pressor stress, when endothelial-mediated vasodilation should occur. Conclusions Asymptomatic women with DM demonstrate reduced coronary flow velocity during the second minute of cold pressor stress, indicating coronary endothelial dysfunction.
Abiraterone Acetate to Lower Androgens in Women With Classic 21-Hydroxylase Deficiency
Auchus, Richard J. , Buschur, Elizabeth , Chang, Alice Y. , Hammer, Gary D. , Ramm, Carole A., Madrigal, David, Gonzalez, Martha, Xu, Xu Steven , Smit, Johan W., Jiao, James, Yu, Margaret K. , Wang, George C.

The Journal of Clinical Endocrinology & Metabolism | April 29, 2014 | Volume: 99 | Issue: 8 | Pages: 2763-2770

10.1210/jc.2014-1258 Get It