Aggressive statin therapy significantly improves endothelial function in CVD
MedWire News: Researchers report that aggressive lipid-lowering therapy may be better for endothelial function than less aggressive therapy in patients with cardiovascular disease (CVD).
Previous studies have demonstrated that statins, and the reduction in low-density lipoprotein cholesterol (LDL) cholesterol levels they bring about, improve clinical outcomes in patients with CVD.
Accordingly, guidelines in the EU and USA have recently been amended to recommend intensive lipid-lowering therapy.
However, it is not yet clear how aggressive versus standard statin treatment affects endothelial function.
Anna Dominiczak (University of Glasgow, UK) and colleagues studied endothelial function in 226 individuals with severe coronary artery disease (CAD) who had undergone coronary artery bypass surgery in either 2003 (n=121) or 2007 (n=105).
The average statin dose given to these patients increased, in line with guidelines, from 26 mg/day in 2003 to 37 mg/day in 2007, allowing the researchers to directly compare the effects of more versus less aggressive therapy on vascular function.
As reported in the journal Atherosclerosis, the increases in statin dose had no significant effect on levels of high-density lipoprotein cholesterol but did result in significant reductions in total cholesterol levels from 4.8 mmol/l (185.8 mg/dl) in 2003 to 4.0 mmol/l (154.8 mg/dl) in 2007. Aggressive statin therapy also significantly reduced levels of LDL cholesterol, from 3.0 to 2.0 mmol/l (116.1 to 77.4 mg/dl).
In addition, endothelial-dependent vasodilation in isolated segments of the saphenous vein was 44% in patients from the 2007 cohort versus 28% in those from the 2003 cohort. In both cohorts, endothelial function correlated strongly and independently with LDL cholesterol levels, which explained about 16% of the variability in endothelial function.
The authors say that their study is limited by its retrospective, noncontrolled design, and because data collection methods differed between 2003 and 2007.
Furthermore, they point out that their results are at odds with a recently published controlled clinical trial suggesting that aggressive lipid lowering does not necessarily lead to better vascular outcome compared with standard therapy.
Nevertheless, they write: "In summary, we have found a significant improvement of endothelial function in patients with severe CAD that is paralleled by treatment of lipids to lower targets.
“Being an independent predictor of morbidity and mortality, this improvement of endothelial function may serve as surrogate evidence for improved survival of patients with CAD as a result of new secondary prevention guidelines.”
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By Philip Ford