Lipoprotein-associated phospholipase A2 predicts cardiovascular events in dialyzed patients

Background Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) is a serine lipase that enhances the instability of the atherosclerotic plaques. While in the general and cardiac population Lp-PLA(2) is recognized as an important determinant of cardiovascular (CV) accidents, no data are available for the renal population. The aim of this study was to evaluate the relationship between Lp-PLA2 and acute CV events in hemodialyzed patients. Methods We enrolled 102 dialyzed patients, 63% male, age 71 years (59-78), 35% with diabetes, 54% hypertension, 40% coronary artery disease and 31% peripheral vascular disease. They were investigated for Lp-PLA2 (cut-off <194 nmol/min/ml), lipoprotein profile and the occurrence of acute CV events and death in the subsequent 3 years of follow-up. Results The median (interquartile ranges) levels of Lp-PLA2, total-, HDL-, LDL-cholesterol and ApoB/ApoA lipoprotein ratio were 184.5 (156.5-214.5) nmol/min/ml, 158 (127-191) mg/dl, 41 (33-51) mg/dl, 79 (63-102) mg/dl and 0.72 (0.58-0.89), respectively. In 42% of patients, Lp-PLA2 was > 194 nmol/min/ml and total- and LDL-cholesterol were higher, as well as CV morbidity and mortality. During follow-up, 51% of patients developed at least one CV event; the median survival time was 36 months, with a total and CV mortality of 42 and 29%, respectively. At multivariate Cox regression, Lp-PLA2 > 194 nmol/min/ml (HR = 2.98, p = 0.005), age (HR = 1.03, p = 0.029), diabetes (HR = 2.86, p = 0.002) and hypertension (HR = 2.93, p=0.002) were independently associated with time to CV events. Conclusions Lp-PLA2 activity is elevated among dialyzed patients and is an independent risk factor for acute CV events in a mean follow-up of 3 years.