Indexed on: 28 May '19Published on: 29 Mar '19Published in: The Journal of clinical endocrinology and metabolism
In end-stage renal disease (ESRD), serum high-density lipoprotein cholesterol (HDL-C) level is not an accurate predictor of mortality, partly because it does not necessarily correlate with indices of HDL function. Paraoxonase (PON) is a major enzyme constituent of HDL, and key component of HDL antioxidant activity. Apolipoprotein (Apo) A-I is the core HDL structural protein which plays a major role in various aspects of HDL function. We sought to examine PON activity and Apo A-I levels in ESRD patients versus healthy controls. PON/Arylesterase activity was measured in 499 maintenance hemodialysis (MHD) patients and 24 healthy controls with similar distributions of age, sex and race/ethnicity. Serum acrolein-modified Apo A-I was measured in 30 MHD patients and 10 healthy controls. Multilevel Cox models were used to assess associations between PON activity, Apo A-I and HDL-C levels with 12-month all-cause mortality. PON activity was significantly lower in MHD patients versus controls. Furthermore, acrolein-modified Apo A-I levels were higher in MHD patients versus controls. In fully adjusted models, high PON activity was associated with lower 12-month mortality, whereas no difference of mortality risk was observed across HDL-C levels. The combination of high PON and low Apo A-I compared to low PON and low Apo A-I was associated with lower mortality risk. In MHD patients, PON activity had a stronger association with 12-month mortality than HDL-C. Future studies are needed to examine the role of these markers as potential diagnostic and therapeutic tools in ESRD. Copyright © 2019 Endocrine Society.