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

To determine whether moderate obesity (BMI ≥ 30 kg/m²) 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.

41 middle aged, non-diabetic moderately obese (BMI 34.7±4.0 kg/m²) and non obese (BMI 24.3±2.6 kg/m²) 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).

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/m² (P=0.02), but not men. There was no difference between in vivo endothelial function (FMD%, FMD mm) by BMI category. Sex specific analysis showed FMD% was lower in women with BMI ≥ 30 kg/m² compared to those with BMI < 30 kg/m² (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).

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