Myeloperoxidase levels are not associated with carotid atherosclerosis progression in patients with familial hypercholesterolemia

IntroductionMyeloperoxidase (MPO), an antimicrobial enzyme of the innate immune system, has been proposed to exert a wide array of pro-atherogenic effects throughout all stages of the atherosclerotic process. In view of the potent anti-inflammatory effects of statins in vitro, we evaluated the impact of statin therapy on plasma MPO levels in patients with heterozygous familial hypercholesterolemia (FH), treated with either intensive or conventional lipid-lowering therapy. Furthermore, we evaluated the relation between MPO levels and atherosclerosis progression, as determined by intima media thickness (IMT).MethodsWe measured plasma MPO levels, lipoprotein profiles, high sensitivity-C-reactive protein (hs-CRP) as well as IMT of carotid artery segments in 122 FH patients at baseline and after 2-year treatment with atorvastatin 80 mg or simvastatin 40 mg QD.ResultsBaseline median MPO values were 147 pM (interquartile range (IQR) 122-217) and 144 pM (IQR 118-216) and these increased significantly to 221 pM (IQR 144-290) and 255 pM (IQR 152-324) during 2-year follow-up in both the atorvastatin 80 mg and simvastatin 40 mg group, respectively. There was no correlation between MPO levels and IMT progression, change in lipoproteins or hs-CRP.ConclusionIn FH patients, statins do not prevent an increase in MPO levels during follow-up. Moreover, MPO levels are not associated with atherosclerosis progression in these patients.