Adiponectin in peritoneal dialysis patients: A comparison with hemodialysis patients and subjects with normal renal function

Background: Adiponectin, a cytokine with anti-inflammatory properties that is secreted from adipose tissue, is associated with insulin resistance. Adiponectin has been shown to be a predictor of cardiovascular events in both the general population and patients undergoing hemodialysis (HD); however, its role in peritoneal dialysis (PD) analogues remains unclear. Methods: Serum adiponectin levels, measured by means of enzyme-linked immunosorbent assay in subjects with normal renal function and patients undergoing HD or PD (28 subjects in each group), were analyzed to establish the relationship between adiponectin and lipid levels, as well as insulin resistance. In the second study, 104 PD patients were recruited to analyze the relationships between serum adiponectin level and residual renal and peritoneal function and C-reactive protein (CRP) level. Independent factors for serum adiponectin level were determined from multiple linear regression. Results: No significant difference was shown comparing serum adiponectin levels of PD and HD patients; however, both were significantly greater than those of control subjects (P<0.01). Negative associations were shown between adiponectin and triglyceride (TG; P<0.01) and insulin levels (P<0.05) and homeostatic model assessment of insulin resistance (P<0.01) for the former 2 groups; however, a positive association was shown for high-density lipoprotein (HDL) level (P<0.05). Neither HD nor PD removed adiponectin significantly, with levels for the PD group negatively associated with residual renal function (P<0.01) and CRP level (P<0.001). PD patients administered glucose-lowering agents had lower adiponectin levels; however, lipid-lowering agents and renin-angiotensin blockades did not appear to affect them. Independent determinants for serum adiponectin level in PD patients were TG, HDL, and CRP levels and body mass index, after adjustment for age, sex, PD therapy duration, and diabetes. Adiponectin levels were not associated with left ventricular mass or ejection fraction. As for HD patients, PD patients had high adiponectin levels; adiponectin was not removed effectively using either of the studied dialysis modalities. In addition to a significant relationship with the components of insulin resistance, adiponectin level was associated with CRP level in these patients. Conclusion: These results indicate that adiponectin level in PD patients may be a good indicator of cardiovascular disease risk.