title: Assessment of glucose metabolism in polycystic ovary syndrome: HbA1c or fasting glucose compared with the oral glucose tolerance test as a screening method.
abstract: OBJECTIVE
  Are HbA1c and fasting glucose (FG) useful in predicting the presence of prediabetes and type 2 diabetes (T2DM) in a large cohort of women with polycystic ovary syndrome (PCOS)?
  
  
  CONCLUSIONS
  HbA1c and FG are not suitable as screening tools for prediabetes in a large cohort of PCOS women but do show a good level of agreement with T2DM.
  
  
  BACKGROUND
  Women with PCOS have an increased risk of prediabetes and T2DM. As performing an oral glucose tolerance test (OGTT) is time consuming, HbA1c and FG have been suggested as screening tools for prediabetes and T2DM.
  
  
  METHODS
  This was a cross-sectional study of 671 women with PCOS conducted from 2006 to 2012.
  
  
  METHODS
  The study was carried out at the endocrinological outpatient department of the Medical University of Graz, Austria. We performed 75 g 2-h OGTTs and measured HbA1c in 671 women with PCOS aged 16-45 years with a median BMI of 24.2 (21.3-30.1) kg/m². PCOS was defined according to the Rotterdam criteria. Prediabetes (FG 100-125 mg/dl and/or 2-h glucose 140-199 mg/dl and/or HbA1c 5.7-6.4%) and T2DM (FG ≥ 126 mg/dl and/or 2-h glucose ≥200 mg/dl and/or HbA1c ≥ 6.5%) were diagnosed according to the American Diabetes Association (ADA) criteria. Levels of agreement between different definitions were analyzed using κ-index.
  
  
  RESULTS
  According to the ADA criteria, we found prediabetes and T2DM in 12.8% (n = 76) and 1.5% (n = 9) of PCOS women, respectively. When using elevated HbA1c (5.7-6.4%) for defining prediabetes, 19 (3.2%) of all PCOS women had prediabetes with a κ-index of 0.36. When using elevated FG (100-125 mg/dl) for defining prediabetes, 31 (5.2%) of all the PCOS women were diagnosed with prediabetes with a κ-index of 0.05. Further, elevated HbA1c (≥6.5% defining T2DM) was found in six (0.9%) PCOS women (κ-index 0.80), and elevated FG (≥126 mg/dl diagnosing T2DM) was found in seven PCOS women (1%; κ-index 0.82).
  
  
  CONCLUSIONS
  Our results are limited to an Austrian cohort of PCOS women diagnosed by Rotterdam criteria with a median BMI in the normal weight range.
  
  
  CONCLUSIONS
  Our results are in line with results from previous smaller PCOS cohorts. Our findings do not support the recommendation that FG or HbA1c can be used for the screening of prediabetes in women with PCOS. For such women, OGTT should be performed for screening of prediabetes. Whether this finding is generalizable to other cohorts remains to be determined in further studies.
authors.affiliation: Department of Internal Medicine, Medical University of Graz, Graz, Austria. elisabeth.lerchbaum@medunigraz.at
authors.forename: E
authors.initials: E
authors.lastname: Lerchbaum
authors.forename: V
authors.initials: V
authors.lastname: Schwetz
authors.forename: A
authors.initials: A
authors.lastname: Giuliani
authors.forename: B
authors.initials: B
authors.lastname: Obermayer-Pietsch
mesh_terms: D000293:Adolescent; D000328:Adult; D001317:Austria / Q000453:epidemiology; D001786:Blood Glucose / Q000032:analysis; D015992:Body Mass Index; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000032:analysis; D006785:Hospitals, University; D006801:Humans; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital; D050177:Overweight / Q000150:complications; D011085:Polycystic Ovary Syndrome / Q000097:blood / Q000150:complications / Q000378:metabolism / Q000503:physiopathology*; D011236:Prediabetic State / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D015995:Prevalence; D012307:Risk Factors; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: HbA1c; oral glucose tolerance test; polycystic ovary syndrome; prediabetes; type 2 diabetes