Cardiovascular risk factors as determinants of endothelium-dependent and endothelium-independent vascular reactivity in the general population

Objectives We examined to what extent the variation in risk factors for cor onary heart disease (CHD) and the Framingham risk score (FRS) explain the v ariation in vascular reactivity in adults aged 30 to 53 Years. Background The role of risk factors in determining vascular reactivity in t he general population has not been quantified. Methods Risk factors for CHD were measured, and the FRS was calculated in 6 9 healthy volunteers. Lipoprotein particle size was measured using proton-n uclear magnetic resonance spectroscopy. Forearm plethysmography was used to assess blood flow responses to acetylcholine (ACh), bradykinin (BK), glyce ryl trinitrate (GTN), noradrenaline and N-G-monomethyl-L-arginine (L-NMMA). Results Lower ACh and BK responses were associated with a higher body mass index (BMI), a higher total cholesterol to high-density lipoprotein (HDL) c holesterol ratio, lower HDL cholesterol and a cigarette smoking habit (all p<0.05). Higher low-density lipoprotein (LDL) cholesterol was also associat ed with a lower BK response (p=0.001). A decreased GTN response was associa ted with a higher BMI and total cholesterol to HDL cholesterol ratio (both p<0.05). A decreased L-NMMA response was associated with a smoking habit (p <0.001). Lipoprotein particle sizes did not independently predict any vascu lar response. A high FRS was associated with a reduced response to ACh (p=0 .07), BK (p=0.003) and L-NMMA (p=0.003), and the relationship was stronger in women than in men. Altogether, risk factors explained 13%, 9%, 8% and 15 % of the response to ACh, BK, GTN and L-NMMA, respectively. Conclusions Lipids, BMI and smoking are important determinants of vascular reactivity. The FRS is predictive of agonist-stimulated, endothelium-depend ent vasodilation and basal NO release. However, much of the variation in th e vascular responses to these drugs, at this age, remains unexplained. (J A m Coll Cardiol 2001;38:1814-20) (C) 2001 by the American College of Cardiol ogy.