Table 1.

Population characteristics by diabetes status, NHANES 1999 through 2006

CharacteristicDiabetes StatusPa
Diagnosed DiabetesUndiagnosed DiabetesPrediabetesNo Diabetes
n82629922724791
Mean FPG (mg/dl)153.0166.5107.190.7<0.001
Mean glycohemoglobin (%)7.217.045.495.23<0.001
Mean age (years)57.758.852.042.4<0.001
Gender (%)<0.001
    male48.463.059.943.9
    female51.637.040.156.1
Race/ethnicity (%)b<0.001
    non-Hispanic white61.774.074.272.3
    non-Hispanic black15.111.87.811.4
    Mexican American8.46.67.77.1
Education (%)<0.001
    less than high school29.031.722.816.6
    high school or more71.068.377.283.4
Household income (%)<0.001
    <$20,00026.624.118.315.0
    $20,000–$44,99935.643.429.128.5
    $45,000–$74,99920.115.926.626.7
    ≥$75,00017.716.626.129.8
Insurance (%)<0.001
    not insured8.916.817.319.4
    insured91.183.282.780.6
Routine site for health care (%)<0.001
    no2.5c10.315.816.5
    yes97.589.784.283.5
Smoking (%)0.020
    every day18.617.419.022.3
    sometimes/not at all81.482.681.077.7
BMI (kg/m2; %)<0.001
    ≥3055.355.139.724.6
    <3044.744.960.375.4
Self-reported hypertension (%)<0.001
    yes60.354.636.620.9
    no39.745.263.479.1
ACEIs/ARBs (%)<0.001
    yes20.811.07.53.0
    no79.289.092.597.0
  • Diagnosed diabetes, self-reported of diabetes diagnosis; undiagnosed diabetes, FPG ≥126 mg/dl and no self-report of diabetes; prediabetes, FPG ≥100 and <126 mg/dl and no self-report of diabetes; no diabetes, FPG <100 mg/dl and no self-report of diabetes. BMI, body mass index.

  • a Across all four groups of diabetes status, by χ2 (categorical variables) and Kruskal-Wallis (continuous variables) tests.

  • b Other race/ethnicity not shown because of small sample sizes, but individuals in category are included in all analyses.

  • c Unreliable estimate: Relative SE ≥30%.