Objective: To explore the relationship between plasma adipocyte fatty acid-binding protein (A-FABP), adiponectin (APN) levels and A-FABP/APN ratio with femoral intima-media thickness (FA-IMT) and endothelium-dependent vasodilation in patients with newly diagnosed type 2 diabetes mellitus (T2DM).
Methods: Plasma A-FABP and APN in 133 patients with newly diagnosed T2DM were measured by enzyme-linked immunosorbent assays. FA-IMT, endothelium-dependent and independent vasodilation of brachial artery was measured by high-resolution vascular ultrasound. Upper quartile of FA-IMT was regarded as a criterion of elevated FA-IMT, defined as early atherosclerosis (AS). The patients were subdivided into low FA-IMT group (FA-IMT < 0.60 mm, n = 34), middle FA-IMT group (0.60 mm </= FA-IMT < 0.73 mm, n = 33), high FA-IMT group (0.73 mm </= FA-IMT < 0.80 mm, n = 33) and early AS group (FA-IMT >/= 0.80 mm, n = 33).
Results: Plasma A-FABP/APN ratio was higher in early AS group than in low IMT control group [A-FABP/APN x 1000, 3.9(2.8 approximately 6.1) vs 2.9(1.8 approximately 5.7), P < 0.05]. FA-IMT correlated positively with plasma A-FABP/APN ratio (r = 0.216, P = 0.006) and negatively with APN (r = -0.179, P = 0.020). After adjusted for age, gender and BMI, FA-IMT still correlated positively with plasma A-FABP/APN ratio (r = 0.217, P = 0.007) and negatively with APN (r = -0.172, P = 0.026). Endothelium-dependent vasodilation correlated negatively with plasma A-FABP/APN ratio (r = -0.166, P = 0.028). After adjusted for age, gender and BMI, endothelium-dependent vasodilation still correlated negatively with plasma A-FABP/APN ratio (r = -0.153, P = 0.042).
Conclusion: Plasma A-FABP/APN ratio is closely associated with FA-IMT and endothelium-dependent vasodilation. Plasma A-FABP/APN ratio may be a better clinical marker of AS and endothelial dysfunction than A-FABP or APN alone in patients with newly diagnosed T2DM.