Plasma myeloperoxidase level and peripheral arterial disease

Abstract

Background Myeloperoxidase (MPO) is involved in a multitude of inflammatory processes involving oxidative modification of soluble components and cellular surfaces. Thus, MPO plays a key role in promoting atherosclerosis via oxidative stress by modification of both high- and low-density lipoprotein and production of other bioactive molecules. A polymorphism (MPO 463G>A, rs2333227) results in different expression rates of MPO. We aimed to assess whether MPO could be of clinical use as a risk marker for vascular disease in a high-risk group. Material and methods Plasma MPO levels of 406 patients suffering from peripheral arterial disease (PAD) were measured on an Abbott Architect i2000sr and grouped into patients with high (>115ng/mL) and low (< 115ng/mL) MPO levels. Genotyping of rs2333227 was performed on an ABI TaqMan 7900HT RT-PCR thermocycler. Results The relative risk of major adverse cardiovascular events (MACE) for patients with high plasma MPO is 1·2 (95%CI: 1·038-1·377, P<0·05), initial event-free periods in male patients are significantly longer in patients with MPO <115ng/mL (mean=875days compared with mean=734days, P<0·05) In smokers, an increased hazard ratio was computed for patients with high MPO levels (HR=3·127, 95%CI: 1·258-7·772, P<0·05). Effects of MPO [-463A] allele on initial MACE-free intervals did not persist after multivariate analysis. Conclusions Hence, we suggest consideration of plasma MPO for risk stratification of MACE in patients with PAD. In contrast, MPO-463G>A is not an independent risk factor for MACE in patients suffering from PAD. © 2011 The Authors. European Journal of Clinical Investigation © 2011 Stichting European Society for Clinical Investigation Journal Foundation.