Effect of a short term primary prevention program on endothelium-dependentvasodilation in adults at risk for atherosclerosis

BACKGROUND: Endothelium-dependent vasodilation is impaired in asymptomatic subjects with risk factors for atherosclerosis. PURPOSE: To determine whether a three-month integrative primary prevention program can improve endothelial function in asymptomatic subjects with risk factors for atherosclerosis. PATIENTS AND METHODS: Twenty-two asymptomatic middle-aged men and women (13 men and nine women) aged 55 +/- 7 years with sedentary lifestyle and dysli pidemia (low density lipoprotein [LDL] level greater than 3.4 mmol/L) under went an exercise test, determination of fasting blood lipid levels and noni nvasive measurement of brachial artery reactivity before and three months a fter the beginning of a prevention program. The program consisted of exerci se training (three times per week) and National Cholesterol Education Progr am step 1 diet in all subjects. A smoking cessation program was offered whe n applicable (six patients). Brachial artery diameter was measured by using high resolution ultrasound at rest, during reactive hyperemia (flow-mediat ed dilation [FMD], which is endothelium-dependent) and after sublingual nit roglycerin (NTG) (endothelium-independent vasodilation). RESULTS: After three months, peak oxygen uptake increased significantly fro m 25.4 +/- 4.9 to 27.5 +/- 4.8 mL/kg/min (P<0.005), and LDL level decreased significantly from 4.48 +/- 0.92 to 4.00 +/- 0.83 mmol/L (P<0.005). FMD an d NTG responses assessed as percentage of diameter change from baseline, ho wever, did not change (FMD 5.4 +/- 4.3% before and 5.1 +/- 3.9% at three mo nths, not significant; NTG 8.4 +/- 3.8% before and 7.4 +/- 4.5% at three mo nths, not significant). CONCLUSIONS: Short term application of the currently recommended lifestyle intervention in adults with coronary risk factors did not improve vascular endothelial function. Longer and more aggressive programs may be needed to improve vascular function in subjects with risk factors for atherosclerosis .