Introduction: Adiponectin is increased in end-stage renal disease. However, efforts to clarify the cause of that increase and its clinical effects have been inconclusive. The aim of this study was to compare serum adiponectin levels of dialysis patients against healthy individuals and evaluate the relationship among adiponectin levels, IL-6, TNF- alpha and left ventricular mass index (LVMI).
Methods: Adiponectin, IL-6 and TNF- alpha measurements and echocardiographic evaluations were performed in 36 hemodialysis, 30 continuous ambulatory peritoneal dialysis (CAPD) patients and 22 healthy volunteers. Adiponectin, IL-6 and TNF- alpha levels were measured by ELISA.
Results: Adiponectin was found to be higher in hemodialysis (52.78+/-18.01 ng/mL) and CAPD (52.96+/-17.53 ng/mL) groups than controls (28.36+/-13.20 ng/ mL; p=0.0003, p=0.0003, respectively). No difference was observed between the hemodialysis and CAPD groups. Adiponectin was positively correlated with IL-6 (r=0.293, p=0.02), TNF- alpha (r=0.458, p=0.0003) and LVMI (r=0.283, p=0.02). In the partial correlation analysis, by controlling for body mass index, the correlation between adiponectin and TNF- alpha (r=0.466, p=0.0003) persisted. When IL-6 was controlled with TNF- alpha, the relation between adiponectin and LVMI disappeared (r=0.145, p=0.30). In the linear regression analysis, with adiponectin as the dependent variable, and IL-6, TNF- alpha and body mass index as independent variables, a significant relationship was found between adiponectin and TNF- alpha (beta=0.488, p=0.001).
Conclusions: Increased adiponectin seems to be associated with increased proinflammatory cytokines in dialysis patients, and this relationship suggests adiponectin may have a role in the development of left ventricular hypertrophy.