Short- and long-term influence of diet and simvastatin on brachial artery endothelial function

BACKGROUND: Endothelium-dependent dilation (EDD) has often been studied in patients with hypercholesterolemia without overt coronary atherosclerosis where an improvement after statin treatment has been documented within few weeks. The aim of the study was to assess the short-term effect of diet as well as short- and long-term effect of simvastatin on EDD in patients with hypercholesterolemia and ischemic heart disease. METHODS: In 43 male patients with hypercholesterolemia and ischemic heart disease, EDD of the brachial artery was measured at baseline, after 3 months on a lipid-lowering diet, and after another 1, 3 and 12 months on simvastatin at 40 mg/day. RESULTS: Three months changes in EDD were neither influenced by diet nor short-term simvastatin therapy (4.9% vs. 4.9% vs. 4.8%, p=ns). Twelve months simvastatin treatment, however, significantly improved EDD by 32.7% (4.9% vs. 6.5%, p=0.007). By regression analysis an individual adjusted increase in EDD during the simvastatin treatment period was seen (coefficient 0.132 a month, p=0.002). A significant reduction in total cholesterol of 31.0% (6.1+/-0.8 vs. 4.2+/-0.7, p<0.001) and LDL cholesterol of 42.6% (4.0+/-0.8 vs. 2.2+/-0.6, p<0.001) was observed. CONCLUSION: EDD is improved after long-term simvastatin therapy; however, neither did 3 months diet or 3 months simvastatin therapy has influence on the EDD.