Adipose tissue-derived adiponectin exerts insulin-sensitizing, anti-atherogenic and anti-inflammatory effects. Blunted plasma adiponectin levels were associated with hypertension in some cross-sectional studies. To study their interrelationships, plasma adiponectin levels, hypertension (HT), insulin resistance (IR) and coronary artery disease (CAD) severity were determined in 400 nondiabetic patients undergoing coronary angiography, HT being diagnosed by the European Society of Hypertension/Cardiology guidelines, IR by HOMA index and CAD by angiography-based modified Duke Index score. CAD was present in 62% and absent in 38% (non-CAD group) of patients. Plasma adiponectin levels were inversely related to the CAD score (P=0.029) and an independent predictor of the coronary atherosclerotic burden. By contrast, there was no association between adiponectin and blood pressure values, whereas adiponectin levels were lower in patients with IR than in those without IR within the non-CAD group (P=0.007), but not within the CAD group. The authors discuss the point that antihypertensive and/or vasoactive treatment might have divergent effects on plasma adiponectin levels.