Background: Type 2 Diabetes Mellitus (T2DM) is associated with an increased risk for cardiovascular disease. Postprandial hyperlipemia as characteristic for T2DM, may cause a systemic inflammatory response potentially resulting in vascular dysfunction.

Methods: We explored the postprandial changes in lipids, inflammatory markers and endothelial function in 16 male patients with T2DM on intensive insulin treatment who underwent a standardized oral fat load test. Inflammation was determined by measurements of leukocyte activation markers using flow-cytometry and pro-inflammatory cytokines by ELISA. Vascular function was assessed by pulse wave velocity (PWV) and augmentation index (Aix). Postprandial increased where evaluated by repeated-measurement analysis of variance (ANOVA).

Results: After the oral fat load, postprandial triglycerides (TG) were maximal at 4 hours (+122.5%; p=0.001), apolipoprotein B48 at 4 hours (+37.6%; p=0.037) and circulating leukocytes at 4 hours (+24.4%; p<0.001). All leukocyte activation markers (monocyte CD35 and CD11b and neutrophil CD35, CD11b and CD66) showed a significant postprandial increase, maximal at 6 hours (p<0.05 for all).

Soluble intracellular adhesion molecule 1 (sICAM-1) and Interleukin 1b (IL-1b) did no change postprandially. A significant decrease in vascular function, defined by an increase PWV (+10.9%; p=0.003) and a decreased Aix (-16.0%; p=0.03) was observed after 4 hours.

Conclusions: In patients with T2DM on an intensive insulin regimen, postprandial lipemia is associated with increased leukocyte count, activation of leukocyte activation markers and vascular dysfunction.