title: Distribution of HbA(1c) levels for children and young adults in the U.S.: Third National Health and Nutrition Examination Survey.
abstract: OBJECTIVE
  To describe the distribution of HbA(1c) levels among children and young adults in the U.S. and to evaluate the effects of age, sex, race/ethnicity, socioeconomic status, parental history of diabetes, overweight, and serum glucose on HbA(1c) levels.
  
  
  METHODS
  We analyzed HbA(1c) data from the Third National Health and Nutrition Examination Survey, 1988-1994, for 7,968 participants aged 5-24 years who had not been treated for diabetes. After adjusting for the complex sample design, we compared the distributions of HbA(1c) in subgroups and developed multiple linear regression models to examine factors associated with HbA(1c).
  
  
  RESULTS
  Mean HbA(1c) level was 4.99% (SD 0.50%) and varied from 4.93% (95% CI +/-0.04) in non-Hispanic whites to 5.05% (+/-0.02) in Mexican-Americans to 5.17% (+/-0.02) in non-Hispanic blacks. There were very small differences among subgroups. Within each age- group, among men and women, among overweight and nonoverweight subjects, and at any level of education, mean HbA(1c) levels were higher in non-Hispanic blacks than in non-Hispanic whites. After adjusting for confounders, HbA(1c) levels for non-Hispanic blacks (5.15%, 95% CI +/-0.04) and Mexican-Americans (5.01%, +/-0.04) were higher than those for non-Hispanic whites (4.93%, +/-0.04).
  
  
  CONCLUSIONS
  These data provide national reference levels for HbA(1c) distributions among Americans aged 5-24 years and show statistically significant racial/ethnic differences in HbA(1c) levels that are not completely explained by demographic and health-related variables.
authors.affiliation: Division of Diabetes Translation, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia 30341, USA. zna2@cdc.gov
authors.forename: Jinan B
authors.initials: JB
authors.lastname: Saaddine
authors.forename: Anne
authors.initials: A
authors.lastname: Fagot-Campagna
authors.forename: Deborah
authors.initials: D
authors.lastname: Rolka
authors.forename: K M Venkat
authors.initials: KM
authors.lastname: Narayan
authors.forename: Linda
authors.initials: L
authors.lastname: Geiss
authors.forename: Mark
authors.initials: M
authors.lastname: Eberhardt
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Flegal
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D044383:Black People; D002648:Child; D002675:Child, Preschool; D003920:Diabetes Mellitus / Q000208:ethnology; D003922:Diabetes Mellitus, Type 1 / Q000208:ethnology*; D003924:Diabetes Mellitus, Type 2 / Q000208:ethnology*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D008297:Male; D017058:Mexican Americans / Q000706:statistics & numerical data; D009749:Nutrition Surveys; D009765:Obesity; D017678:Sex Distribution; D014481:United States; D044465:White People; D001741:Black or African American
chemical_list: D006442:Glycated Hemoglobin