Table 1—

Unadjusted percentage of A1C <7% and unadjusted geometric mean A1C among U.S. adults with diagnosed diabetes aged ≥20 years

NHANES 1999–2000
NHANES 2001–2002
NHANES 2003–2004
P for linear trendP for interaction*
nA1C <7%nA1C <7%nA1C <7%
Total40437.0 (4.3)44649.7 (3.6)48456.8 (3.6)0.001
Men20337.0 (4.6)22446.6 (4.4)24455.3 (4.5)0.0070.913
Women20137.0 (5.9)22252.7 (4.2)24058.1 (4.6)0.007
White§12041.8 (6.5)18853.6 (4.2)21863.5 (4.4)0.0080.324
African American11028.1 (4.1)10144.2 (4.2)10443.5 (4.9)0.021
Mexican American13228.9 (4.4)11842.4 (3.1)13834.0 (3.9)0.388
nA1C (%)nA1C (%)nA1C (%)P for linear trendP for interaction*
Total4047.60 ± 0.154467.24 ± 0.144847.01 ± 0.090.002
Men2037.56 ± 0.132247.37 ± 0.192447.11 ± 0.190.1340.439
Women2017.64 ± 0.242227.12 ± 0.142406.92 ± 0.090.006
White§1207.34 ± 0.211887.04 ± 0.122186.78 ± 0.100.0240.401
African American1107.97 ± 0.181017.53 ± 0.191047.42 ± 0.180.032
Mexican American1327.95 ± 0.211187.62 ± 0.141387.75 ± 0.200.657
  • Data are percent (SE) or geometric means ± SE unless otherwise indicated. P for linear trend determined from linear contrasts generated from orthogonal polynomial coefficients.

  • * Interactions tested in log-binomial regression models for dichotomized concentration of A1C and in a linear regression model for log-transformed A1C.

  • Unweighted sample size.

  • Weighted percentage or mean.

  • § Results for race or ethnicity designation “other” not shown because of small sample size.