Accumulating evidence suggests a cross‐sectional association between oxidative stress and type 2 diabetes (T2D). Systemic oxidative stress, as measured by oxidized LDL (oxLDL), has been correlated with visceral fat. We examined the relationship between oxLDL, and T2D‐ and obesity‐related traits in a bi‐racial sample of 2985 subjects at baseline and after 7 years of follow‐up.

We examined six T2D‐related traits (T2D status, HbA_1c, fasting glucose, insulin, adiponectin and HOMA‐IR) as well as six obesity‐related traits (obesity status, BMI, leptin, % body fat, visceral and subcutaneous fat mass) using logistic and linear regression models.

In all subjects at baseline, oxLDL was positively associated with T2D (OR = 1.3, 95% CI:1.1–1.5), fasting glucose (ß = 0.03 ± 0.006), HbA_1c (ß = 0.02 ± 0.004), fasting insulin (ß = 0.12 ± 0.02), HOMA‐IR (ß = 0.13 ± 0.02) and negatively with adiponectin (ß = −0.16 ± 0.03), (all p < 0.001). The strength and magnitude of these associations did not differ much between blacks and whites. In both blacks and whites, oxLDL was also associated with obesity (OR = 1.3, 95% CI:1.1–1.4) and three of its related traits (ß = 0.60 ± 0.14 for BMI, ß = 0.74 ± 0.17 for % body fat, ß = 0.29 ± 0.06 for visceral fat; all p < 0.001). Furthermore, of four traits measured after 7 years of follow‐up (fasting glucose, HbA1c, BMI and % fat), their relationship with oxLDL was similar to baseline observations. No significant association was found between oxLDL and incident T2D. Interestingly, oxLDL was significantly associated with % change in T2D‐ and obesity‐related traits in whites but not in blacks.

Our data suggest that systemic oxidative stress may be a novel risk factor for T2D and obesity. Copyright © 2009 John Wiley & Sons, Ltd.