title: Fasting plasma glucose and hemoglobin A1c in identifying and predicting diabetes: the strong heart study.
abstract: OBJECTIVE
  To compare fasting plasma glucose (FPG) and HbA(1c) in identifying and predicting type 2 diabetes in a population with high rates of diabetes.
  
  
  METHODS
  Diabetes was defined as an FPG level ≥ 126 mg/dL or an HbA(1c) level ≥ 6.5%. Data collected from the baseline and second exams (1989-1995) of the Strong Heart Study were used. RESULTS For cases of diabetes identified by FPG ≥ 126 mg/dL, using HbA(1c) ≥ 6.5% at the initial and 4-year follow-up diabetes screenings (or in identifying incident cases in 4 years) among undiagnosed participants left 46% and 59% of cases of diabetes undetected, respectively, whereas for cases identified by HbA(1c) ≥ 6.5%, using FPG ≥ 126 mg/dL left 11% and 59% unidentified, respectively. Age, waist circumference, urinary albumin-to-creatinine ratio, and baseline FPG and HbA(1c) levels were common significant risk factors for incident diabetes defined by either FPG or HbA(1c); triglyceride levels were significant for diabetes defined by HbA(1c) alone, and blood pressure and sibling history of diabetes were significant for diabetes defined by FPG alone. Using both the baseline FPG and HbA(1c) in diabetes prediction identified more people at risk than using either measure alone. CONCLUSIONS Among undiagnosed participants, using HbA(1c) alone in initial diabetes screening identifies fewer cases of diabetes than FPG, and using either FPG or HbA(1c) alone cannot effectively identify diabetes in a 4-year periodic successive diabetes screening or incident cases of diabetes in 4 years. Using both criteria may identify more people at risk. The proposed models using the commonly available clinical measures can be applied to assessing the risk of incident diabetes using either criterion.
authors.affiliation: Center for American Indian Health Research, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA. wenyu-wang@ouhsc.edu
authors.forename: Wenyu
authors.initials: W
authors.lastname: Wang
authors.forename: Elisa T
authors.initials: ET
authors.lastname: Lee
authors.forename: Barbara V
authors.initials: BV
authors.lastname: Howard
authors.forename: Richard R
authors.initials: RR
authors.lastname: Fabsitz
authors.forename: Richard B
authors.initials: RB
authors.lastname: Devereux
authors.forename: Thomas K
authors.initials: TK
authors.lastname: Welty
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000175:diagnosis / Q000208:ethnology; D005215:Fasting; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D015994:Incidence; D007198:Indians, North American / Q000706:statistics & numerical data*; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D011237:Predictive Value of Tests; D012307:Risk Factors
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human