Table 1

Means (or proportions) of demographic, lifestyle, and type 2 diabetes–related factors by quartile of oxidative stress markers*

2000–2001 variable (except where indicated)Quartiles of year 15 F2Isop
Quartiles of year 15 oxLDL
1st quartile2nd quartile3rd quartile4th quartilePtrend1st quartile2nd quartile3rd quartile4th quartilePtrend
n693693695693652650652652
Demographics
    Age (years)40.3 ± 3.540.2 ± 3.540.2 ± 3.640.0 ± 3.70.240.1 ± 3.640.2 ± 3.640.2 ± 3.540.2 ± 3.70.9
    White (%)58.355.857.854.60.462.056.655.853.20.01
    Men (%)57.156.046.322.4<0.000135.739.950.855.5<0.0001
    Education (grade of school completed)15.3 ± 2.615.1 ± 2.515.0 ± 2.514.7 ± 2.4<0.000115.4 ± 2.615.0 ± 2.515.0 ± 2.514.8 ± 2.4<0.0001
Lifestyle
    Alcohol intake (g/day)9.2 ± 24.810.3 ± 18.212.3 ± 24.013.1 ± 33.10.0511.5 ± 21.59.9 ± 20.011.9 ± 31.312.0 ± 28.50.6
    Physical activity (exercise units)399 ± 295394 ± 295357 ± 286286 ± 253<0.0001382 ± 289354.4 ± 283364 ± 292339 ± 2700.01
    Current smoker (%)14.519.521.925.4<0.000119.220.419.222.00.5
Body fat components
    Waist circumference (cm)85.4 ± 12.386.7 ± 11.887.7 ± 13.191.6 ± 14.3<0.000181.9 ± 12.186.3 ± 13.189.4 ± 12.393.7 ± 12.0<0.0001
    BMI (kg/m2)26.2 ± 4.727.0 ± 4.727.9 ± 5.931.0 ± 7.2<0.000125.9 ± 5.427.9 ± 6.428.5 ± 5.529.9 ± 5.8<0.0001
    Estimated body fat (%)29.6 ± 8.630.7 ± 9.233.3 ± 10.140.3 ± 10.5<0.000131.9 ± 9.933.9 ± 10.833.5 ± 10.634.5 ± 10.4<0.0001
Oxidative stress markers
    ln (F2Isop) (ng/l)3.47 ± 0.23.81 ± 0.14.09 ± 0.14.58 ± 0.3<0.00013.98 ± 0.54.00 ± 0.43.98 ± 0.54.0 ± 0.50.7
    ln (oxLDL) (units/l)4.32 ± 0.34.36 ± 0.34.32 ± 0.44.33 ± 0.30.73.89 ± 0.24.25 ± 0.14.47 ± 0.14.73 ± 0.1<0.0001
    ln (sum of five carotenoids) (μg/dl)4.74 ± 0.44.64 ± 0.44.55 ± 0.44.41 ± 0.4<0.00014.63 ± 0.44.59 ± 0.44.58 ± 0.44.54 ± 0.40.0002
    ln (ascorbic acid) (μg/dl)2.29 ± 0.42.21 ± 0.42.15 ± 0.52.10 ± 0.5<0.00012.22 ± 0.52.22 ± 0.42.16 ± 0.52.16 ± 0.40.02
    ln (α-tocopherol) (μg/dl)0.84 ± 0.10.80 ± 0.10.76 ± 0.10.73 ± 0.1<0.00010.79 ± 0.20.78 ± 0.20.77 ± 0.20.78 ± 0.20.08
    ln (γ-tocopherol) (μg/dl)0.19 ± 0.10.21 ± 0.10.22 ± 0.10.24 ± 0.1<0.00010.21 ± 0.10.21 ± 0.10.21 ± 0.10.22 ± 0.10.008
HOMA-IR (μU · l−1 · mmol−1 · l−1)
    ln (HOMA-IR) at year 01.09 ± 0.31.11 ± 0.31.11 ± 0.31.14 ± 0.30.00081.06 ± 0.31.12 ± 0.31.12 ± 0.31.15 ± 0.3<0.0001
    ln (HOMA-IR) at year 71.26 ± 0.41.26 ± 0.31.27 ± 0.31.33 ± 0.4<0.00011.17 ± 0.31.28 ± 0.41.28 ± 0.31.38 ± 0.4<0.0001
    ln (HOMA-IR) at year 101.23 ± 0.31.26 ± 0.31.27 ± 0.41.33 ± 0.4<0.00011.17 ± 0.31.26 ± 0.31.29 ± 0.41.36 ± 0.4<0.0001
    ln (HOMA-IR) at year 151.24 ± 0.41.27 ± 0.41.31 ± 0.41.40 ± 0.4<0.00011.14 ± 0.31.28 ± 0.41.34 ± 0.41.46 ± 0.4<0.0001
    ln (HOMA-IR) at year 201.31 ± 0.41.35 ± 0.41.38 ± 0.41.43 ± 0.4<0.00011.22 ± 0.41.34 ± 0.41.37 ± 0.41.52 ± 0.4<0.0001
  • Data are means ± SD unless otherwise indicated.

  • *All variables were measured at year 15, except as indicated.

  • †Sum of five carotenoids: α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin, and lycopene.

  • ‡Adjusted for year 15 HDL cholesterol, LDL cholesterol, and triglycerides (25).