Background Adiponectin is an adipocyte-derived protein with atherogenic and anti-inflammatory properties. It has been previously reported that low adiponectin levels had been found in patients with high risk for cardiovascular disease. The aim of the study was to compare the level of adiponectin and leptin and their relationship with markers of cardiovascular risk in patients with coronary artery disease (CAD) with and without primary hypertension.
Material and methods In our ongoing study we included 156 non-diabetic men with CAD: 105 hypertensive (CAD+HT): 56.8 ± 8.3 yrs, mean BMI 27.1 ± 4.5 kg/m² and 51 normotensive (CAD-NT) (mean age 55.5 ± 9.2 yrs, mean BMI 25.3 ± 6.7 kg/m²). Blood samples for adiponectin, leptin, insulin, C-reactive protein (CRP), homocysteine, neuropeptide Y and other biochemical evaluations were taken under basal conditions. ABPM was performed using SpaceLabs 9020. Patients with significant coronary angiography lesions (documented stenosis of ≥ 30% of luminal diameter principal coronary arteries) were included into the study.
Results In CAD-HT group adiponectin plasma concentration was lower than in CAD-NT group (5.1 ± 2.3 vs. 6.9 ± 3.1 μg/ml, p < 0.01) and leptin plasma level was higher in CAD-HT (8.0 ± 5.8 vs. 6.4 ± 4.3 μg/ml, p = 0.04). In both groups significant negative correlations between adiponectin and leptin plasma levels were found. In CAD-HT group plasma insulin level (14 ± 9.3) was significantly higher as compared to CAD-NT (10.8 ± 7.6). Plasma homocysteine, neuropeptide Y, lipoproteins (a) levels and HOMA-IR were not significantly different in both groups. No correlations were found between adiponectin and leptin levels and systolic and diastolic blood pressure. Plasma adiponectin levels were negatively correlated with pulse pressure (day-period of ABPM); (r = -0.34, p = 0.041 ) in CAD–HT group only. In CAD-HT strong correlation between adiponectin plasma level and left ventricular mass and E/A index was found. CAD-HT was characterized by stronger association between adiponectin plasma level and CRP as compared with CAD-NT (-0.48, p = 0.01 vs. -0.43, p = 0.02).
Conclusion In patients with coronary atherosclerosis and hypertension decreased adiponectin plasma level was found. It suggests that hypoadiponectinemia may be a new risk factor for coronary heart disease.