Table 2

Mean differences in flicker light–induced vasodilation between participants with diabetes and normal control subjects and by grades of diabetic retinopathy severity in participants with diabetes

GroupsnMean dilationAge- and sex-adjusted
Multivariable adjusted*
Mean difference (95% CI)PMean difference (95% CI)P
Arteriolar
    Control subjects1033.46(Reference)(Reference)
    Diabetic patients2241.43−1.87 (−1.43 to −2.31)<0.001−1.58 (−1.05 to −2.11)<0.001
        Type 1 diabetes1.57−1.99 (−1.46 to −2.52)<0.001−1.71 (−1.10 to −2.32)<0.001
        Type 2 diabetes1.24−1.78 (−1.29 to −2.27)<0.001−1.48 (−0.90 to −2.07)<0.001
Diabetic retinopathy severity
    None1.76(Reference)(Reference)
    Minimal NPDR1.39−0.37 (0.29 to −1.03)0.28−0.53 (0.16 to −1.22)0.13
    Early-moderate NPDR1.01−0.75 (−0.23 to −1.28)0.005−0.85 (−0.29 to −1.40)0.003
    Severe NPDR1.24−0.51 (0.15 to −1.16)0.13−0.58 (0.12 to −1.28)0.10
Venular
    Control subjects3.98(Reference)(Reference)
    Diabetic patients2.83−0.98 (−0.57 to −1.39)<0.001−1.07 (−0.56 to −1.57)<0.001
        Type 1 diabetes2.84−1.11 (−0.62 to −1.61)<0.001−1.36 (−0.78 to −1.94)<0.001
        Type 2 diabetes2.83−0.88 (−0.42 to −1.34)<0.001−0.83 (−0.27 to −1.38)0.004
Diabetic retinopathy severity
    None3.19(Reference)(Reference)
    Minimal NPDR2.94−0.49 (0.10 to −1.09)0.10−0.10 (0.60 to −0.79)0.78
    Early-moderate NPDR2.40−1.11 (−0.63 to −1.58)<0.001−0.67 (−0.11 to −1.23)0.02
    Severe NPDR2.32−1.16 (−0.55 to −1.77)<0.001−0.65 (0.06 to −1.35)0.07
  • Data are %.

  • *Adjustment for age, sex, fasting cholesterol and triglyceride levels, use of antihypertensive and lipid-lowering medications, current smoking status, and fasting glucose (for analysis of diabetic retinopathy severity).