Moderate Obesity and Endothelial Dysfunction in Humans: Influence of Gender and Systemic Inflammation.

Objective: To determine whether moderate obesity (BMI ≥ 30 kg/m) is associated with impaired conduit and microvascular endothelial function, and whether men or women are more susceptible to impairment of endothelial function related to moderate obesity.

Design And Methods: 41 middle aged, non-diabetic moderately obese (BMI 34.7±4.0 kg/m) and non obese (BMI 24.3±2.6 kg/m) subjects of both sexes underwent noninvasive studies of endothelial function (brachial reactivity) and measurements of endothelial dependent vasodilation of gluteal subcutaneous arterioles to acetylcholine (Ach).

Results: Endothelium dependent vasodilation to Ach was decreased in the moderately obese compared to the non-obese (P<0.001). Stratified analysis based on sex showed impairment of arteriolar endothelial function in women BMI ≥ 30 kg/m (P=0.02), but not men. There was no difference between endothelial function (FMD%, FMD mm) by BMI category. Sex specific analysis showed FMD% was lower in women with BMI ≥ 30 kg/m compared to those with BMI < 30 kg/m (P=0.02). No differences were seen in men based on BMI category (P=0.18). In women, high sensitivity C-reactive protein (hsCRP) correlated with BMI (ρ=0.68, P=0.006).

Conclusion: Moderate obesity is associated with impaired resistance arteriolar endothelial function. This is more prominent in women than men and is associated with systemic inflammation.