Assessment of Myeloperoxidase and Oxidative α1-Antitrypsin in Patients on Hemodialysis

Abstract

Background and objectives: The present study assesses the effects of the oxidative stress marker, myeloperoxidase (MPO), and the possible MPO-related oxidative stress marker, oxidative α₁-antitrypsin (oxAT), on carotid intima-media thickness (CIMT) and protein-energy wasting (PEW) in patients on hemodialysis (HD). Design, setting, participants, & measurements: Blood samples were obtained from 383 patients before HD to measure WBC count, serum albumin, lipids, high-sensitivity C-reactive protein (CRP), α₁-antitrypsin (AT), interleukin-6, oxidative LDL-C, MPO, and oxAT. We assessed both CIMT and the geriatric nutritional risk index (GNRI) in this cross-sectional competitive study. Results: Levels of MPO and oxAT correlated. Myeloperoxidase was associated with max-CIMT, and oxAT correlated with max-CIMT and GNRI. Multivariate linear regression models showed that MPO and oxAT were independent predictors of increasing max-CIMT, whereas oxAT, but not MPO, independently correlated with GNRI. In four combined MPO and oxAT groups classified according to median values, a multinomial logistic regression model showed that high MPO together with high oxAT was independently associated with increased max-CIMT. Moreover, the OR for max-CIMT with positive PEW and high MPO was significantly increased in the four groups with combined MPO and PEW. Conclusions: High MPO with high oxAT and high MPO with PEW seem to contribute to plaque formation in patients on HD, whereas elevated MPO or oxAT alone might not predict increasing CIMT. In contrast, a high oxAT value seems to be an independent predictor of PEW in patients on HD.