Carotid intima media thickness is associated with plasma lipoprotein-associated phospholipase A(2) mass in nondiabetic subjects but not in patients with type 2 diabetes

Background A recent meta-analysis showed that both plasma lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) mass and activity independently predict cardiovascular events. Notably, Lp-PLA(2) activity but not mass was found to be a determinant of cardiovascular outcome in type 2 diabetes mellitus. We questioned whether relationships of carotid intima media thickness (IMT), a measure of subclinical atherosclerosis, with Lp-PLA(2) mass differ between diabetic and nondiabetic subjects. Materials and methods Relationships of IMT with plasma Lp-PLA(2) mass (turbidimetric immunoassay) were compared in 74 patients with type 2 diabetes and in 64 nondiabetic subjects. Results IMT was increased (P=0.016), but plasma Lp-PLA(2) mass was decreased in patients with diabetes compared to nondiabetic subjects (277 +/- 66 vs. 327 +/- 62 mu g L-1, P Conclusions Plasma Lp-PLA(2) may relate to early stages of atherosclerosis development. In diabetes mellitus, in contrast, the association of IMT with plasma Lp-PLA(2) mass is abolished, which could be partly ascribed to redistribution of Lp-PLA(2) mass from apolipoprotein B-containing lipoproteins towards HDL. These findings raise questions about the usefulness of plasma Lp-PLA(2) mass measurement as a marker of subclinical atherosclerosis in type 2 diabetes mellitus.