Effects of Simvastatin on Augmentation Index Are Transient: Outcomes From a Randomized Controlled Trial

Area of Science:

• Cardiovascular Medicine
• Pharmacology
• Clinical Trials

Background:

• Statins are known to improve endothelial function.
• Their impact on arterial stiffness and aortic blood pressure in middle-aged individuals remains unclear.
• This study investigated statin's vascular effects beyond lipid-lowering.

Purpose of the Study:

• To evaluate the effect of simvastatin on central aortic blood pressure, aortic augmentation index, and brachial artery flow-mediated dilation in middle-aged adults.
• To assess the persistence of vascular changes over 18 months.
• To identify predictors of vascular changes.

Main Methods:

• A prospective, randomized, double-blind, placebo-controlled trial involving 88 middle-aged adults (40-72 years).
• Participants received either simvastatin 40 mg daily or a placebo for 18 months.
• Vascular parameters were measured at baseline and at 6, 12, and 18 months.

Main Results:

• Low-density lipoprotein cholesterol significantly decreased in the statin group compared to placebo (P<0.01).
• No significant differences were observed in central blood pressure or flow-mediated dilation between groups (P>0.2).
• Augmentation index showed a transient decrease in the statin group at 12 months (P=0.007) but returned to baseline levels by 18 months (P=0.3).

Conclusions:

• Statin therapy demonstrated a short-term reduction in aortic stiffness (augmentation index) at 12 months.
• This effect on arterial stiffness was not sustained at 18 months, despite ongoing low-density lipoprotein cholesterol reduction.
• Findings suggest a potentially transient impact of statins on aortic stiffness in this population.