Effect of statin therapy added to ACE-inhibitors on blood pressure control and endothelial functions in normolipidemic hypertensive patients.

OBJECTIVE Endothelium-dependent vasodilatation is impaired in hypertension. Statins have been shown to improve endothelial functions in hyperlipidemic subjects. We aimed to investigate the effect of statins on endothelium-dependent flow mediated dilatation (FMD) and blood pressure (BP) in normocholesterolemic hypertensive patients. METHODS This randomized prospective study consisted of 56 patients with newly diagnosed essential hypertension. All patients received angiotensin converting enzyme (ACE) inhibitor lisinopril (5 mg/day) as antihypertensive therapy, and half of them were randomized to simvastatin(20mg/day) irrespective of serum lipid levels. All subjects underwent brachial artery ultrasonographic examination for the measurement of FMD before randomization and at the end of 12 weeks treatment. RESULTS A total of 39 patients completed the study (21 patients in the statin + ACE inhibitor group, and 18 patients in the ACE-inhibitor alone group). Blood pressure levels were substantially reduced in both groups after treatment. In statin+ ACE-inhibitor group systolic pressure reduced by 23% (p=0.0001) and diastolic BP reduced by 23% (p=0.0001). In ACE-inhibitor alone group these ratios were 20% (p=0.001) and 21% (p=0.001), respectively. Meanwhile, pulse pressure (PP) decreased by 25% in statin+ ACE-inhibitor group (P=0.0001) and by 16% in ACE inhibitor-alone group (p=0.0051). Baseline FMD was significantly impaired in overall patients with hypertension as compared with healthy controls (13+/-8 vs. 24+/-8 %, P = 0.001). After treatment FMD decreased by 23% in lisinopril alone group (p=0.054). There were no correlations between FMD improvement, LDL reduction, BP or PP changes in both groups. CONCLUSION Addition of simvastatin to ACE-inhibitor treatment in newly diagnosed hypertensive patients with normal cholesterol levels, significantly reduced PP and facilitated BP control, but did not affect endothelium-dependent dilatation. Further long-term large scale studies are needed to clarify the effect of various statins on endothelial functions of either hypercholesterolemic or normocholesterolemic hypertensive patients.