['Pigment epithelium-derived factor (PEDF) could play a protective role against atherosclerosis. However, there is no clinical study to examine the relationship between serum level of PEDF and atherosclerosis in humans.', 'The study involved 317 consecutive outpatients in Kurume University Hospital (220 male and 97 female) with a mean age of 62.1±9.1. We examined whether serum level of PEDF were independently associated with vascular inflammation evaluated by [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and intima-media thickness (IMT) in carotid artery in humans. Carotid [(18)F]-FDG uptake, an index of vascular inflammation within the atherosclerotic plaques, was measured as standardized uptake value (SUV). Mean serum PEDF level, carotid SUV and IMT values were 13.5±1.1 μg/mL, 1.34±0.19, and 0.71±0.15 mm, respectively. In multiple stepwise regression analysis, estimated glomerular filtration rate (p<0.001), males (p<0.001), homeostasis model assessment of insulin resistance index (p<0.05), heart rate (p<0.05), triglycerides (p<0.05), carotid IMT (p<0.05), waist circumference (p<0.05) and carotid SUV (p<0.05) were independently correlated to PEDF level (R(2)=0.332).'] Is serum level of pigment epithelium-derived factor a marker of atherosclerosis in humans?