IMPACT OF CLASSICAL CARDIOVASCULAR RISK FACTORS ON RETINAL VASCULAR FUNCTION IN NON-DIABETIC OBESE MALE SUBJECTS: PP.11.439

Abstract

Objective: Obese subjects frequently reveal multiple cardiovascular risk factors that each per se is associated with retinal vascular impairment. However, the impact of the individual cardiovascular risk factor on retinal vascular function in obese subjects is unknown. Methods: 51 never-treated male non-diabetic subjects with a BMI of at least 30 kg/m2 were included in this study. Retinal vascular function was assessed in vivo using scanning laser Doppler flowmetry by examining the vasodilatory increase of retinal capillary blood flow (RCF) in response to flicker light and the vasoconstrictive decrease of RCF in response to infusion of the nitric oxide synthase inhibitor N-monomethyl-L-arginine (L-NMMA). Results: Neither BMI, nor waist circumference or waist-to-hip circumference ratio were related with the percent change of RCF to flicker light or to L-NMMA. In contrast, systolic blood pressure (r = −0.334, P = 0.018), glucose 2 h after 75 mg glucose challenge (r = -0.290, P = 0.048), total cholesterol (r = −0.410, P = 0.003), LDL-cholesterol (r = −0.397, P = 0.005) and RCF at baseline (r = −0.292, P = 0.039) were related with the percent change of RCF to flicker light, and total cholesterol (r = −0.312, P = 0.029), LDL-cholesterol (r = −0.329, P = 0.023) and RCF at baseline (r = −0.468, P = 0.001) were related with the percent change of RCF to L-NMMA. Multiple linear regression analyses revealed that LDL-cholesterol (ß = −0.348, P = 0.021) and systolic blood pressure (ß = −0.285, P = 0.044) were the main contributors of the vasodilatory response to flicker light, whereas solely RCF at baseline (ß = -0.447, P = 0.007) independently determined the vasoconstrictor response to L-NMMA. Conclusion: LDL-cholesterol, and to a lesser extent also systolic blood pressure, but not BMI nor any parameter of abdominal obesity, emerged as the major contributors of retinal vascular dysfunction in non-diabetic obese male subjects.